Patent Publication Number: US-8985911-B2

Title: Wafer carrier track

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     This application claims the benefit of priority of PCT application no. PCT/US10/27540 filed on Mar. 16, 2010 which claims the benefit of priority of U.S. Provisional Patent Application Ser. Nos. 61/160,694; 61/160,696; 61/160,700; 61/160,701; 61/160,703; 61/160,690; and 61/160,699 all filed on Mar. 16, 2009 which are all hereby incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     Embodiments of the invention generally relate to apparatuses and methods for vapor deposition, and more particularly, to chemical vapor deposition systems, reactors, and processes thereof. 
     2. Description of the Related Art 
     Photovoltaic or solar devices, semiconductor devices, or other electronic devices are usually manufactured by utilizing a variety of fabrication processes to manipulate the surface of a substrate. These fabrication processes may include deposition, annealing, etching, doping, oxidation, nitridation, and many other processes. Epitaxial lift off (ELO) is a less common technique for fabricating thin film devices and materials in which layers of materials are deposited to and then removed from a growth substrate. An epitaxial layer, film, or material is grown or deposited on a sacrificial layer which is disposed on the growth substrate, such as a gallium arsenide wafer, by a chemical vapor deposition (CVD) process or a metallic-organic CVD (MOCVD) process. Subsequently, the sacrificial layer is selectively etched away in a wet acid bath, while the epitaxial material is separated from the growth substrate during the ELO etch process. The isolated epitaxial material may be a thin layer or film which is usually referred to as the ELO film or the epitaxial film. Each epitaxial film generally contains numerous layers of varying compositions relative to the specific device, such as photovoltaic or solar devices, semiconductor devices, or other electronic devices. 
     The CVD process includes growing or depositing the epitaxial film by the reaction of vapor phase chemical precursors. During a MOCVD process, at least one of the chemical precursors is a metallic-organic compound—that is—a compound having a metal atom and at least one ligand containing an organic fragment. 
     There are numerous types of CVD reactors for very different applications. For example, CVD reactors include single or bulk wafer reactors, atmospheric and low pressure reactors, ambient temperature and high temperature reactors, as well as plasma enhanced reactors. These distinct designs address a variety of challenges that are encountered during a CVD process, such as depletion effects, contamination issues, reactor maintenance, throughput, and production costs. 
     Therefore, there is a need for CVD systems, reactors, and processes to grow epitaxial films and materials on substrates more effectively with less contamination, higher throughput, and less expensive than by currently known CVD equipment and processes. 
     SUMMARY OF THE INVENTION 
     Embodiments of the invention generally relate to apparatuses and methods for chemical vapor deposition (CVD) processes. In one embodiment, a wafer carrier track for levitating and traversing a wafer carrier within a vapor deposition reactor system is provided which includes an upper section of a track assembly disposed over a lower section of the track assembly, a gas cavity formed between the upper and lower sections of the track assembly, a guide path extending along an upper surface of the upper section and two side surfaces extending along and above the guide path and parallel to each other, wherein the guide path extends between the two side surfaces. The wafer carrier track also has a plurality of gas holes within the guide path and extending from the upper surface of the upper section, through the upper section, and into the gas cavity, and an upper lap joint disposed at one end of the track assembly and a lower lap joint disposed at the opposite end of the track assembly, wherein the upper lap joint extends a portion of the guide path and the two side surfaces and the lower lap joint have an upper surface extending further than the guide path and the two side surfaces of the track assembly. In some examples, the upper section and/or the lower section of the track assembly each independently contains quartz. The lower section of the track assembly may be a quartz plate. The upper section and the lower section of the track assembly may be fused together. 
     In other examples, a gas port extends from a side surface of the upper section of the track assembly, through a portion of the upper section of the track assembly, and into the gas cavity. The gas port may be utilized to flow the levitating gas through the side surface of the track assembly, into the gas cavity and out from the plurality of gas holes on the upper surface of the track assembly. The plurality of gas holes may number from about 10 holes to about 50 holes, preferably, from about 20 holes to about 40 holes. Each gas hole may have a diameter within a range from about 0.005 inches to about 0.05 inches, preferably, from about 0.01 inches to about 0.03 inches. 
     In another embodiment, the wafer carrier track has a levitating wafer carrier disposed on the guide path. In some examples, the levitating wafer carrier has at least one indentation pocket disposed within a lower surface. In other examples, the levitating wafer carrier has at least two indentation pockets disposed within a lower surface. 
     In other embodiments, the wafer carrier track system may contain two or more wafer carrier tracks disposed end to end in series. In one embodiment, the wafer carrier track system is provided which includes an upper lap joint of a first wafer carrier track disposed over a lower lap joint of a second wafer carrier track, an exhaust port formed between the upper lap joint of the first wafer carrier track and the lower lap joint of the second wafer carrier track, and a first guide path on an upper surface of the first wafer carrier track aligned with a second guide path on an upper surface of the second wafer carrier track. In some examples, an upper lap joint of the second wafer carrier track may be disposed over a lower lap joint of a third wafer carrier track. 
     In another embodiment, a wafer carrier track for levitating and traversing a wafer carrier within a vapor deposition reactor system is provided which includes a track assembly having a gas cavity formed within, a guide path extending along an upper surface of the track assembly, a plurality of gas holes within the guide path and extending from the upper surface of the track assembly and into the gas cavity, and an upper lap joint disposed at one end of the track assembly and a lower lap joint disposed at the opposite end of the track assembly, wherein the upper lap joint extends a portion of the guide path and the lower lap joint has an upper surface extending further than the guide path of the track assembly. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       So that the manner in which the above recited features of the invention can be understood in detail, a more particular description of the invention, briefly summarized above, may be had by reference to embodiments, some of which are illustrated in the appended drawings. It is to be noted, however, that the appended drawings illustrate only typical embodiments of this invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. 
         FIGS. 1A-1E  depict a CVD reactor according to embodiments described herein; 
         FIG. 1F  depicts a CVD reactor coupled to a temperature regulation system according to another embodiment described herein; 
         FIGS. 2A-2C  depict a reactor lid assembly according to embodiments described herein; 
         FIG. 2D  depicts a reactor lid support according to an embodiment described herein; 
         FIG. 3  depicts a reactor body assembly according to embodiments described herein; 
         FIGS. 4A-4E  depict a wafer carrier track according to embodiments described herein; 
         FIGS. 5A-5D  depict an isolator assembly according to embodiments described herein; 
         FIG. 6  depicts a heating lamp assembly according to embodiments described herein; 
         FIGS. 7A-7D  depict a showerhead assembly according to embodiments described herein; 
         FIGS. 8A-8D  depict an exhaust assembly according to embodiments described herein; 
         FIGS. 9A-9F  depict a CVD system containing multiple CVD reactors according to embodiments described herein; 
         FIGS. 10A-10B  depict lamps according to embodiments described herein; 
         FIGS. 11A-11F  depict a plurality of lamps according to other embodiments described herein; 
         FIGS. 12A-12B  depict a levitating substrate carrier according to another embodiment described herein; and 
         FIGS. 12C-12E  depict other levitating substrate carriers according to another embodiment described herein. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of the invention generally relate to an apparatus and methods of chemical vapor deposition (CVD), such as metallic-organic CVD (MOCVD) processes. As set forth herein, embodiments of the invention are described as they relate to an atmospheric pressure CVD reactor and metal-organic precursor gases. It is to be noted, however, that aspects of the invention are not limited to use with an atmospheric pressure CVD reactor or metal-organic precursor gases, but are applicable to other types of reactor systems and precursor gases. To better understand the novelty of the apparatuses of the invention and the methods of use thereof, reference is hereafter made to the accompanying drawings. 
     According to one embodiment of the invention, an atmospheric pressure CVD reactor is provided. The CVD reactor may be used to provide multiple epitaxial layers on a substrate, such as a gallium arsenide substrate. These epitaxial layers may include aluminum gallium arsenide, gallium arsenide, and phosphorous gallium arsenide. These epitaxial layers may be grown on the gallium arsenide substrate for later removal so that the substrate may be reused to generate additional materials. In one embodiment, the CVD reactor may be used to provide solar cells. These solar cells may further include single junction, hetero-junction, or other configurations. In one embodiment, the CVD reactor may be configured to develop a 2.5 watt wafer on a 10 centimeter by 10 centimeter substrate. In one embodiment, the CVD reactor may provide a throughput range of about 1 substrate per minute to about 10 substrates per minute. 
       FIGS. 1A-1E  depict reactor  100 , a CVD reactor or chamber, as described in an embodiment described herein. Reactor  100  contains reactor lid assembly  200  disposed on reactor body assembly  102 . Reactor lid assembly  200  and components thereof are further illustrated in  FIGS. 2A-2D  and reactor body assembly  102  is further illustrated in  FIG. 3 . 
     Reactor lid assembly  200  contains an injector or isolator, isolator assembly  500 , disposed between two showerheads, showerhead assemblies  700 . Reactor lid assembly  200  also contains exhaust assembly  800 .  FIG. 1C  depicts reactor  100  containing two deposition stations, such as chamber stations  160 ,  162 . Chamber station  160  contains showerhead assembly  700  and isolator assembly  500  while chamber station  162  contains showerhead assembly  700  and exhaust assembly  800 . In one embodiment, isolator assembly  500  may be used to flow gas to separate both showerhead assemblies  700  from each other, while exhaust assembly  800  may be used to isolate the internal environment of reactor  100  from another reactor connected to faceplate  112 . 
     In many embodiments described herein, each of the showerhead assemblies  700  may be a modular showerhead assembly, each of the isolator assemblies  500  may be a modular isolator assembly, and each of the exhaust assemblies  800  may be a modular exhaust assembly. Any of the showerhead assemblies  700 , the isolator assemblies  500 , and/or the exhaust assemblies  800  may be removed from reactor lid assembly  200 , and replaced with the same or a different assembly as desired for the particular process conditions. The modular assemblies of the showerhead assemblies  700 , the isolator assemblies  500 , and/or the exhaust assemblies  800  may independently be configured for positioning within a CVD reactor system. 
     In alternative embodiments described herein, other configurations of reactor  100  are provided, but not illustrated in the drawings. In one embodiment, reactor lid assembly  200  of reactor  100  contains three exhaust assemblies  800  separated by two showerhead assemblies  700  so that reactor lid assembly  200  sequentially contain a first exhaust assembly, a first showerhead assembly, a second exhaust assembly, a second showerhead assembly, and a third exhaust assembly. In another embodiment, reactor lid assembly  200  of reactor  100  contains three isolator assemblies  500  separated by two showerhead assemblies  700  so that reactor lid assembly  200  sequentially contain a first isolator assembly, a first showerhead assembly, a second isolator assembly, a second showerhead assembly, and a third isolator assembly. 
     In another embodiment, reactor lid assembly  200  of reactor  100  contains two isolator assemblies  500  and one exhaust assembly  800  separated by two showerhead assemblies  700  so that reactor lid assembly  200  sequentially contains a first isolator assembly, a first showerhead assembly, a second isolator assembly, a second showerhead assembly, and a first exhaust assembly. In another example, reactor lid assembly  200  may sequentially contain a first isolator assembly, a first showerhead assembly, a first exhaust assembly, a second showerhead assembly, and a second isolator assembly. In another example, reactor lid assembly  200  may sequentially contain a first exhaust assembly, a first showerhead assembly, a first isolator assembly, a second showerhead assembly, and a second isolator assembly. 
     In another embodiment, reactor lid assembly  200  of reactor  100  contains two exhaust assemblies  800  and one isolator assembly  500  separated by two showerhead assemblies  700  so that reactor lid assembly  200  sequentially contains a first exhaust assembly, a first showerhead assembly, a second exhaust assembly, a second showerhead assembly, and a first isolator assembly. In another example, reactor lid assembly  200  may sequentially contain a first exhaust assembly, a first showerhead assembly, a first isolator assembly, a second showerhead assembly, and a second exhaust assembly. In another example, reactor lid assembly  200  may sequentially contain a first isolator assembly, a first showerhead assembly, a first exhaust assembly, a second showerhead assembly, and a second exhaust assembly. 
     Reactor body assembly  102  contains faceplate  110  on one end and faceplate  112  on the opposite end. Faceplates  110  and  112  may each independently be utilized to couple together additional reactors, similar or different than reactor  100 , or to couple an end cap, an end plate, a wafer/substrate handler, or another device. In one example, faceplate  110  of reactor  100  may be coupled to faceplate  112  of another reactor (not shown). Similar, faceplate  112  of reactor  100  may be coupled to faceplate  110  of another reactor (not shown). A seal, spacer, or O-ring may be disposed between two joining faceplates. In one embodiment, the seal may contain a metal, such as nickel or a nickel alloy. In one example, the seal is a knife edge metal seal. In another embodiment, the seal contains a polymer or an elastomer, such as a KALREZ® elastomer seal, available from DuPont Performance Elastomers L.L.C. In another embodiment, the seal may be a helix seal or an H-seal. The seal or O-ring should form a gas tight seal to prevent, or greatly reduce ambient gas from entering reactor  100 . Reactor  100  may be maintained with little or no oxygen, water, or carbon dioxide during use or production. In one embodiment, reactor  100  may be maintained with an oxygen concentration, a water concentration, and/or a carbon dioxide concentration independently of about 100 ppb (parts per billion) or less, preferably, about 10 ppb or less, more preferably, about 1 ppb or less, and more preferably, about 100 ppt (parts per trillion) or less. 
     Sides  120  and  130  extend along the length of reactor body assembly  102 . Side  120  has upper surface  128  and side  130  has upper surface  138 . Upper surfaces  114  and  116  of reactor body assembly  102  extend between upper surfaces  128  and  138 . Upper surface  114  is on reactor body assembly  102  just inside and parallel to faceplate  110  and upper surface  116  is on reactor body assembly  102  just inside and parallel to faceplate  112 . Gas inlet  123  is coupled to and extends from side  120 . The levitation gas or carrier gas may be administered into reactor  100  through gas inlet  123 . The levitation gas or carrier gas may contain nitrogen, helium, argon, hydrogen, or mixtures thereof. 
       FIG. 1F  depicts reactor  100 , including reactor body assembly  102  and reactor lid assembly  200 , coupled to temperature regulation system  190 , according to one embodiment described herein. Temperature regulation system  190  is illustrated in  FIG. 1F  as having three heat exchangers  180   a ,  180   b , and  180   c . However, temperature regulation system  190  may have 1, 2, 3, 4, 5, or more heat exchangers coupled to and in fluid communication with the various portions of reactor  100 . Each of the heat exchangers  180   a ,  180   b , or  180   c  may contain at least one liquid supply  182  and at least one liquid return  184 . Each liquid supply  182  may be coupled to and in fluid communication with inlets on reactor  100  by conduit  186  while each liquid return  184  may be coupled to and in fluid communication with outlets on reactor  100  by conduit  186 . Conduits  186  may include pipes, tubing, hoses, other hollow lines, or combinations thereof. Valve  188  may be used on each conduit  186  between liquid supply  182  and an inlet or between liquid return  184  and an outlet. 
     Reactor body assembly  102  is coupled to and in fluid communication with at least one heat exchanger as part of the heat regulation system. In some embodiments, reactor body assembly  102  may be coupled to and in fluid communication with two, three, or more heat exchangers.  FIG. 1B  depicts inlet  118   a  and outlet  118   b  coupled to and in fluid communication with lower portion  104  of reactor  100  and with the heat regulation system. 
     In one embodiment, inlets  122   a ,  122   b , and  122   c , and outlets  126   a ,  126   b , and  126   c  are coupled to and extend from side  120 . At least one heat exchanger is coupled to and in fluid communication with inlets  122   a ,  122   b , and  122   c , and outlets  126   a ,  126   b , and  126   c . Inlets  122   a ,  122   b , and  122   c  may receive a liquid from the heat exchangers while outlets  126   a ,  126   b , and  126   c  send the liquid back to the heat exchanger. In one embodiment, each inlet  122   a ,  122   b , or  122   c  is positioned in a lower position than each respective outlet  126   a ,  126   b , or  126   c , so that flowing liquid from each inlet  122   a ,  122   b , or  122   c  upwardly flows through each connecting passageway to each respective outlet  126   a ,  126   b , or  126   c.    
     In another embodiment, inlets  132   a ,  132   b , and  132   c , and outlets  136   a ,  136   b , and  136   c  are coupled to and extend from side  130 . At least one heat exchanger is coupled to and in fluid communication with inlets  132   a ,  132   b , and  132   c , and outlets  136   a ,  136   b , and  136   c . Inlets  132   a ,  132   b , and  132   c  may receive a liquid from the heat exchanger while outlets  136   a ,  136   b , and  136   c  send the liquid back to the heat exchanger. 
       FIGS. 1C-1D  illustrate reactor body assembly  102  containing fluid passageways  124   a ,  124   b ,  124   c ,  134   a ,  134   b , and  134   c . In one example, fluid passageway  124   a  extends within side  120  and along a partial length of reactor body assembly  102 . Fluid passageway  124   a  is coupled to and in fluid communication with inlet  122   a  and outlet  126   a . Also, fluid passageway  134   a  extends within side  130  and along a partial length of reactor body assembly  102 . Fluid passageway  134   a  is coupled to and in fluid communication with inlet  132   a  and outlet  136   a.    
     In another example, fluid passageway  124   b  extends within the shelf or bracket arm  146  within reactor body assembly  102  and along a partial length of reactor body assembly  102 . Fluid passageway  124   b  is coupled to and in fluid communication with inlet  122   b  and outlet  126   b . Also, fluid passageway  134   b  extends within the shelf or bracket arm  146  within reactor body assembly  102  and along a partial length of reactor body assembly  102 . Fluid passageway  134   b  is coupled to and in fluid communication with inlet  132   b  and outlet  136   b.    
     In another example, fluid passageway  124   c  extends from side  120 , through the width of reactor body assembly  102 , and to side  130 . Fluid passageway  124   c  is coupled to and in fluid communication with inlet  122   c  and outlet  132   c . Also, fluid passageway  124   c  extends from side  130 , through the width of reactor body assembly  102 , and to side  130 . Fluid passageway  124   c  is coupled to and in fluid communication with inlet  126   c  and outlet  136   c.    
     In another embodiment, reactor body assembly  102  contains wafer carrier track  400  and heating lamp assembly  600  disposed therein. Heating lamp system may be used to heat wafer carrier track  400 , wafer carriers, and wafers  90  disposed above and within reactor  100 . Wafer carrier track  400  may be on a shelf, such as bracket arm  146 . Generally, wafer carrier track  400  may be disposed between bracket arm  146  and clamp arm  148 . Bracket arm  146  may contains fluid passageways  124   b  and  134   b  traversing therethrough. 
     In one embodiment, a spacer, such as a gasket or an O-ring may be disposed between the lower surface of wafer carrier track  400  and the upper surface of bracket arm  146 . Also, another spacer, such as a gasket or an O-ring may be disposed between the upper surface of wafer carrier track  400  and the lower surface of clamp arm  148 . The spacers may be used to form space or a gap around wafer carrier track  400 , which aids in the thermal management of wafer carrier track  400 . In one example, the upper surface of bracket arm  146  may have a groove for containing a spacer. Similarly, the lower surface of clamp arm  148  may have a groove for containing a spacer. 
       FIGS. 2A-2C  depict reactor lid assembly  200  according to another embodiment described herein. Reactor lid assembly  200  contains showerhead assembly  700  and isolator assembly  500  (chamber station  160 ) and showerhead assembly  700  and exhaust assembly  800  (chamber station  162 ) disposed on lid support  210 .  FIG. 2D  depicts lid support  210  contained within reactor lid assembly  200 , as described in one embodiment. Lid support  210  has lower surface  208  and upper surface  212 . Flange  220  extends outwardly from lid support  210  and has lower surface  222 . Flange  220  helps support reactor lid assembly  200  when disposed on reactor body assembly  102 . Lower surface  222  of flange  220  may be in physical contact with upper surfaces  114 ,  116 ,  128 , and  138  of reactor body assembly  102 . 
     In one embodiment, showerhead assemblies  700  may be disposed within showerhead ports  230  and  250  of lid support  210 , isolator assembly  500  may be disposed within isolator port  240  of lid support  210 , and exhaust assembly  800  may be disposed within exhaust port  260  of lid support  210 . The geometry of the gas or exhaust assembly generally matches the geometry of the respective port. Each showerhead assembly  700  and showerhead ports  230  and  250  may independently have a rectangular or square geometry. A process path—such as the path in which levitating wafer carrier  480  travels forward along wafer carrier track  400  during fabrication processes—extends along the length of lid support  210  as well as wafer carrier track  400 . 
     Showerhead port  230  has length  232  and width  234  and showerhead port  250  has length  252  and width  254 . Isolator assembly  500  and isolator port  240  may independently have a rectangular or square geometry. Isolator port  240  has length  242  and width  244 . Exhaust assembly  800  and exhaust port  260  may independently have a rectangular or square geometry. Exhaust port  260  has length  262  and width  264 . 
     The process path extends along length  232  of showerhead port  230  and a first showerhead assembly therein, extends along length  242  of isolator port  240  and an isolator assembly therein, extends along length  252  of showerhead port  250  and a second showerhead assembly therein, and extends along length  262  of exhaust port  260  and an exhaust assembly therein. Also, the process path extends perpendicular or substantially perpendicular to width  234  of showerhead port  230  and a first showerhead assembly therein, to width  244  of isolator port  240  and an isolator assembly therein, to width  254  of showerhead port  250  and a second showerhead assembly therein, and to width  264  of exhaust port  260  and an exhaust assembly therein. 
     In some examples, the first showerhead assembly  700 , the isolator assembly  500 , the second showerhead assembly  700 , and the exhaust assembly  800  are consecutively disposed next to each and along a process path which extends along the length of lid support. The isolator assembly  500 , as well as the exhaust assembly  800  may each have a width which is substantially the same or greater than the width of the process path. Also, the isolator assembly  500  or the exhaust assembly  800  may independently have a width which is substantially the same or greater than the width of the first and second showerhead assemblies  700 . 
     In one embodiment, showerhead assemblies  700  independently have a square geometry and isolator assembly  500  and exhaust assembly  800  have a square geometry. In one example, width  244  of isolator port  240  and the width of isolator assembly  500  may extend across the width of the interior of the chamber. In another example, width  264  of exhaust port  260  and the width of exhaust assembly  800  may extend across the width of the interior of the chamber. 
     In some embodiments, width  234  of showerhead port  230 , width  254  of showerhead port  250 , and the width of each showerhead assembly  700  may independently be within a range from about 3 inch to about 9 inches, preferably, from about 5 inches to about 7 inches, for example, about 6 inches. Also, length  232  of showerhead port  230 , length  252  of showerhead port  250  and the length of each showerhead assembly  700  may independently be within a range from about 3 inch to about 9 inches, preferably, from about 5 inches to about 7 inches, for example, about 6 inches. 
     In other embodiments, width  244  of isolator port  240  and the width of isolator assembly  500  may independently be within a range from about 3 inches to about 12 inches, preferably, from about 4 inches to about 8 inches, and more preferably, from about 5 inches to about 6 inches. Also, length  242  of isolator port  240  and the length of the isolator assembly  500  may independently be within a range from about 0.5 inches to about 5 inches, preferably, from about 1 inch to about 4 inches, from about 1.5 inches to about 2 inches. 
     In other embodiments, width  264  of exhaust port  260  and the width of exhaust assembly  800  may independently be within a range from about 3 inches to about 12 inches, preferably, from about 4 inches to about 8 inches, and more preferably, from about 5 inches to about 6 inches. Also, length  262  of exhaust port  260  and the length of the exhaust assembly  800  may independently be within a range from about 0.5 inches to about 5 inches, preferably, from about 1 inch to about 4 inches, from about 1.5 inches to about 2 inches. 
     Reactor lid assembly  200  may be coupled to and in fluid communication with at least one heat exchanger as part of the heat regulation system. In some embodiments, reactor lid assembly  200  may be coupled to and in fluid communication with two, three, or more heat exchanger. 
     The heat regulation system  190  ( FIG. 1F ) of reactor lid assembly  200  contains inlets  214   a ,  216   a , and  218   a  and outlets  214   b ,  216   b , and  218   b , as depicted in  FIG. 2A . Each pair of the inlet and outlet is coupled to and in fluid communication with a passageway extending throughout reactor lid assembly  200 . Inlets  214   a ,  216   a , and  218   a  may receive a liquid from the heat exchanger while outlets  214   b ,  216   b , and  218   b  send the liquid back to the heat exchanger, such as heat exchangers  180   a - 180   c . In some embodiments, the temperature regulation system  190  utilizes heat exchangers  180   a - 180   c  to independently maintain reactor body assembly  102  and/or reactor lid assembly  200  at a temperature within a range from about 250° C. to about 350° C., preferably, from about 275° C. to about 325° C., more preferably, from about 290° C. to about 310° C., such as about 300° C. 
       FIGS. 2B-2C  illustrate fluid passageways  224 ,  226 , and  228 . Fluid passageway  224  is disposed between inlet  214   a  and outlet  214   b , which may be coupled to and in fluid communication to a heat exchanger. Fluid passageway  224  is disposed between showerhead assembly  700  and exhaust assembly  800 . Also, fluid passageway  226  is disposed between inlet  216   a  and outlet  216   b , and fluid passageway  228  is disposed between inlet  218   a  and outlet  218   b , which both may independently be coupled to and in fluid communication to a heat exchanger. Fluid passageway  226  is disposed between showerhead assembly  700  and isolator assembly  500 , and fluid passageway  228  is disposed between showerhead assembly  700  and isolator assembly  500 . 
     Fluid passageway  224  is partially formed between groove  213  and plate  223 . Similarly, fluid passageway  226  is partially formed between groove  215  and plate  225 , and fluid passageway  228  is partially formed between groove  217  and plate  227 . Grooves  213 ,  215 , and  217  may be formed within lower surface  208  of lid support  210 .  FIG. 2D  depicts plates  223 ,  225 , and  227  respectively covering grooves  213 ,  215 , and  217 . 
     In one embodiment, a reactor lid assembly  200  for vapor deposition is provided which includes a first showerhead assembly  700  and an isolator assembly  500  disposed next to each other on a lid support  210 , and a second showerhead assembly  700  and an exhaust assembly  800  disposed next to each other on the lid support  210 , wherein the isolator assembly  500  is disposed between the first and second showerhead assemblies  700  and the second showerhead assembly  700  is disposed between the isolator assembly  500  and the exhaust assembly  800 . 
     In another embodiment, a reactor lid assembly  200  for vapor deposition is provided which includes a chamber station  160  having a first showerhead assembly  700  and an isolator assembly  500  disposed next to each other on a lid support  210 , and a chamber station  162  having a second showerhead assembly  700  and an exhaust assembly  800  disposed next to each other on the lid support  210 , wherein the isolator assembly  500  is disposed between the first and second showerhead assemblies  700  and the second showerhead assembly  700  is disposed between the isolator assembly  500  and the exhaust assembly  800 . 
     In another embodiment, a reactor lid assembly  200  for vapor deposition is provided which includes a first showerhead assembly  700 , an isolator assembly  500 , a second showerhead assembly  700 , and an exhaust assembly  800  consecutively and linearly disposed next to each other on a lid support  210 , wherein the isolator assembly  500  is disposed between the first and second showerhead assemblies  700  and the second showerhead assembly  700  is disposed between the isolator assembly  500  and the exhaust assembly  800 . 
     In another embodiment, a reactor lid assembly  200  for vapor deposition is provided which includes a first showerhead assembly  700 , an isolator assembly  500 , a second showerhead assembly  700 , and an exhaust assembly  800  consecutively and linearly disposed next to each other on a lid support  210 , and a temperature regulation system  190  having at least one liquid or fluid passageway, but often may have two, three, or more liquid or fluid passageways, such as fluid passageways  224 ,  226 , and  228 , extending throughout the lid support  210 . The temperature regulation system  190  further has at least one inlet, such as inlets  214   a ,  216   a , and  218   a , and at least one outlet, such as outlets  214   b ,  216   b , and  218   b , coupled to and in fluid communication with the fluid passageways  224 ,  226 , and  228 . Each of the inlets  214   a ,  216   a , and  218   a  and outlets  214   b ,  216   b , and  218   b  may be independently coupled to and in fluid communication with a liquid reservoir, a heat exchanger, or multiple heat exchangers, such as heat exchangers  180   a ,  180   b , and  180   c . In one example, the liquid reservoir may contain or be a source of water, alcohols, glycols, glycol ethers, organic solvents, or mixtures thereof. 
     In one example, the first showerhead assembly  700  may be disposed between the two independent fluid passageways of the temperature regulation system  190  which extend through the reactor lid assembly  200 . In another example, the second showerhead assembly  700  may be disposed between the two independent fluid passageways of the temperature regulation system  190  which extend through the reactor lid assembly  200 . In another example, the isolator assembly  500  may be disposed between the two independent fluid passageways of the temperature regulation system  190  which extend through the reactor lid assembly  200 . In another example, the exhaust assembly  800  may be disposed between the two independent fluid passageways of the temperature regulation system  190  which extend through the reactor lid assembly  200 . 
     In another embodiment, a reactor lid assembly  200  for vapor deposition is provided which includes a chamber station  160  having a first showerhead assembly  700  and an isolator assembly  500  disposed next to each other on a lid support  210 , a chamber station  162  having a second showerhead assembly  700  and an exhaust assembly  800  disposed next to each other on the lid support  210 , wherein the isolator assembly  500  is disposed between the first and second showerhead assemblies  700 , and the temperature regulation system  190 . 
     In one embodiment, the first showerhead assembly  700 , the isolator assembly  500 , the second showerhead assembly  700 , and the exhaust assembly  800  are consecutively disposed next to each and along the length of lid support  210 . In some embodiments, the isolator assembly  500  may have a longer width than the first or second showerhead assembly  700 . In other embodiments, the isolator assembly  500  may have a shorter length than the first or second showerhead assembly  700 . In some embodiments, the exhaust assembly  800  may have a longer width than the first or second showerhead assembly  700 . In other embodiments, the exhaust assembly  800  may have a shorter length than the first or second showerhead assembly  700 . 
     In some examples, the first showerhead assembly  700 , the isolator assembly  500 , the second showerhead assembly  700 , and the exhaust assembly  800  independently have a rectangular geometry. In other examples, the first showerhead assembly  700  and the second showerhead assembly  700  have a square geometry. The lid support  210  may contain or be made from a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. 
     Embodiments provide that each of the isolator assembly  500  or the first or second showerhead assemblies  700  independently has a body  502  or  702  containing upper portion  506  or  706  disposed on a lower portion  504  or  704 , a centralized channel  516  or  716  extending through the upper portion  506  or  706  and the lower portion  504  or  704 , between inner surfaces  509  or  709  of the body  502  or  702 , and parallel to a central axis  501  or  701  extending through the body  502  or  702  and an optional diffusion plate  530  or  730  having a first plurality of holes  532  or  732  and disposed within the centralized channel  516  or  716 . The isolator assembly  500  or the first or second showerhead assemblies  700  independently have an upper tube plate  540  or  740  having a second plurality of holes  542  or  742  and disposed within the centralized channel  516  or  716  and optionally below the diffusion plate  530  or  730  and a lower tube plate  550  or  750  having a third plurality of holes  552  or  752  and disposed within the centralized channel  516  or  716  below the upper tube plate  540  or  740 . Either of the showerhead assemblies  700  or the isolator assembly  500  independently may further have a plurality of gas tubes  580  or  780  extending from the upper tube plate  540  or  740  to the lower tube plate  550  or  750 , wherein each of the gas tubes  580  or  780  is coupled to and in fluid communication with an individual hole from the second plurality of holes  542  or  742  and an individual hole from the third plurality of holes  552  or  752 . 
     In another embodiment, an exhaust assembly  800  contains a body  802  having an upper portion  806  disposed on a lower portion  804 , a centralized channel  816  extending through the upper portion  806  and the lower portion  804 , between inner surfaces  809  of the body  802 , and parallel to a central axis  801  extending through the body  802 , an exhaust outlet  860  disposed on the upper portion  806  of the body  802 , an optional diffusion plate  830  having a first plurality of holes  832  and disposed within the centralized channel  816 , an upper tube plate  840  having a second plurality of holes  842  and disposed within the centralized channel  816  and optionally below the diffusion plate  830  (if present), a lower tube plate  850  having a third plurality of holes  852  and disposed within the centralized channel  816  below the upper tube plate  840 . The exhaust assembly  800  may further contain a plurality of exhaust tubes  880  extending from the upper tube plate  840  to the lower tube plate  850 , wherein each of the exhaust tubes  880  is coupled to and in fluid communication with an individual hole from the second plurality of holes  842  and an individual hole from the third plurality of holes  852 . 
       FIGS. 4A-4E  depict wafer carrier track  400  according to one embodiment described herein. In another embodiment, wafer carrier track  400  for levitating and traversing a substrate susceptor, such as levitating wafer carrier  480  within a vapor deposition reactor system, such as reactor  100 , is provided which includes an upper segment  410  of wafer carrier track  400  disposed over a lower segment  412  of wafer carrier track  400 . Gas cavity  430  is formed between upper segment  410  and lower segment  412  of wafer carrier track  400 . Two side surfaces  416  extend along upper segment  410  of wafer carrier track  400  and parallel to each other. Guide path  420  extends between the two side surfaces  416  and along upper surface  418  of upper segment  410 . A plurality of gas holes  438  is disposed within guide path  420  and extend from upper surface  418  of upper segment  410 , through upper segment  410 , and into gas cavity  430 . 
     In another embodiment, upper lap joint  440  is disposed at one end of wafer carrier track  400  and lower lap joint  450  is disposed at the opposite end of wafer carrier track  400 , wherein upper lap joint  440  extends along a portion of guide path  420  and side surfaces  416 . Upper lap joint  440  has lower surface  442  extending further than lower segment  412 . Lower lap joint  450  has upper surface  452  extending further than guide path  420  and side surfaces  416  of wafer carrier track  400 . 
     Generally, upper segment  410  and/or lower segment  412  of wafer carrier track  400  may independently contain quartz. In some examples, lower segment  412  of wafer carrier track  400  may be a quartz plate. Upper segment  410  and lower segment  412  of wafer carrier track  400  may be fused together. In one specific example, upper segment  410  and lower segment  412  both contain quartz and are fused together forming gas cavity therebetween. The quartz contained in upper segment  410  and/or lower segment  412  of wafer carrier track  400  is usually transparent, but in some embodiments, portions of wafer carrier track  400  may contain quartz that is opaque. 
     In another embodiment, gas port  434  extends from side surface  402  of wafer carrier track  400  and into gas cavity  430 . In one example, gas port  434  extends through upper segment  410 . The plurality of gas holes  438  may number from about 10 holes to about 50 holes, preferably, from about 20 holes to about 40 holes. Each of the gas holes  438  may have a diameter within a range from about 0.005 inches to about 0.05 inches, preferably, from about 0.01 inches to about 0.03 inches. 
     In other embodiments, a wafer carrier track system may contain two or more wafer carrier tracks  400  disposed end to end in series, as depicted in  FIGS. 4D-4E . In one embodiment, the wafer carrier track system is provided which includes an upper lap joint  440  of a first wafer carrier track  400  disposed over a lower lap joint  450  of a second wafer carrier track  400 , an exhaust port formed between the upper lap joint  440  of the first wafer carrier track  400  and the lower lap joint  450  of the second wafer carrier track  400 , and a first guide path on an upper surface of the first wafer carrier track  400  aligned with a second guide path on an upper surface of the second wafer carrier track  400 . In some examples, an upper lap joint  440  of the second wafer carrier track  400  may be disposed over a lower lap joint  450  of a third wafer carrier track  400  (not shown). 
     In another embodiment, wafer carrier track  400  for levitating and traversing levitating wafer carrier  480  within a vapor deposition reactor system, such as reactor  100 , is provided which includes wafer carrier track  400  having gas cavity  430  formed within, guide path  420  extending along an upper surface of wafer carrier track  400 , a plurality of gas holes  438  within guide path  420  and extending from the upper surface of wafer carrier track  400  and into gas cavity  430 , and an upper lap joint  440  disposed at one end of wafer carrier track  400  and a lower lap joint  450  disposed at the opposite end of wafer carrier track  400 , wherein the upper lap joint  440  extends a portion of guide path  420  and the lower lap joint  450  has an upper surface extending further than guide path  420  of wafer carrier track  400 . 
     At least one side surface may be disposed on wafer carrier track  400  and extends along and above guide path  420 . In some examples, two side surfaces  416  are disposed on wafer carrier track  400  and extend along and above guide path  420 . Guide path  420  may extend between the two side surfaces  416 . In one embodiment, an upper segment  410  of wafer carrier track  400  may be disposed over a lower segment  412  of wafer carrier track  400 . Upper segment  410  of wafer carrier track  400  may have guide path  420  extending along the upper surface. Gas cavity  430  may be formed between upper segment  410  and lower segment  412  of wafer carrier track  400 . In some examples, upper segment  410  and lower segment  412  of wafer carrier track  400  may be fused together. In some embodiments, wafer carrier track  400  contains quartz. Upper segment  410  and lower segment  412  of wafer carrier track  400  may independently contain quartz. In one example, lower segment  412  of wafer carrier track  400  is a quartz plate. 
     In other embodiments, gas port  434  extends from a side surface of wafer carrier track  400  and into gas cavity  430 . Gas port  434  may be utilized to flow the levitating gas through the side surface of wafer carrier track  400 , into gas cavity  430  and out from the plurality of gas holes  438  on the upper surface of wafer carrier track  400 . The plurality of gas holes  438  may number from about 10 holes to about 50 holes, preferably, from about 20 holes to about 40 holes. Each gas hole  438  may have a diameter within a range from about 0.005 inches to about 0.05 inches, preferably, from about 0.01 inches to about 0.03 inches. 
     In another embodiment,  FIGS. 12A-12E  depict levitating wafer carrier  480  which may be used to carry a substrate through a variety of processing chambers including the CVD reactors as described herein, as well as other processing chambers used for deposition or etching. Levitating wafer carrier  480  has short sides  471 , long sides  473 , an upper surface  472 , and a lower surface  474 . Levitating wafer carrier  480  is illustrated with a rectangular geometry, but may also have a square geometry, a circular geometry, or other geometries. Levitating wafer carrier  480  may contain or be formed from graphite or other materials. Levitating wafer carrier  480  usually travels through the CVD reactor with the short sides  471  facing forward while the long sides  473  face towards the sides of the CVD reactor. 
       FIGS. 12A-12B  depict levitating wafer carrier  480  according to one embodiment described herein.  FIG. 12A  illustrates a top view of levitating wafer carrier  480  containing 3 indentations  475  on the upper surface  472 . Wafers or substrates may be positioned within the indentations  475  while being transferred through the CVD reactor during a process. Although illustrated with 3 indentations  475 , the upper surface  472  may have more or less indentations, including no indentations. For example, the upper surface  472  of levitating wafer carrier  480  may contain 0, 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, 12, or more indentations for containing wafers or substrates. In some example, one wafer/substrate or multiple wafers/substrates may be disposed directly on the upper surface  472  which does not have an indentation. 
       FIG. 12B  illustrates a bottom view of levitating wafer carrier  480  containing the indentation  478  on the lower surface  474 , as described in one embodiment herein. The indentation  478  may be used to help levitate levitating wafer carrier  480  upon the introduction of a gas cushion under levitating wafer carrier  480 . A gas flow may be directed at the indentation  478 , which accumulates gas to form the gas cushion. The lower surface  474  of levitating wafer carrier  480  may have no indentations, or may have one indentation  478  ( FIG. 12B ), two indentations  478  ( FIGS. 12C-12E ), three indentations  478  (not shown) or more. Each of the indentations  478  may have straight or tapered sides. In one example, each indentation  478  has tapered sides such that the sides  476  are steeper or more abrupt than the sides  477  which have more of a gradual change of angle. The sides  477  within the indentation  478  may be tapered to compensate for a thermal gradient across levitating wafer carrier  480 . Also, the sides  477  may be tapered or angled to help form a gas pocket and to maintain the gas pocket under levitating wafer carrier  480  while lifting and moving/traversing levitating wafer carrier  480  along wafer carrier track  400 . In another example, the indentation  478  has straight or substantially straight sides and tapered sides such that the sides  476  are straight or substantially straight and the sides  477  have a taper/angle or the sides  477  are straight or substantially straight and the sides  476  have a taper/angle. Alternatively, the indentation  478  may have all straight sides such that the sides  476  and  477  are straight or substantially straight. 
     In another embodiment,  FIGS. 12C-12E  illustrate bottom views of levitating wafer carrier  480  containing two indentations  478  on the lower surface  474 . The two indentations  478  help levitate levitating wafer carrier  480  upon the introduction of a gas cushion under levitating wafer carrier  480 . A gas flow may be directed at the indentations  478 , which accumulates gas to form the gas cushion. The indentations  478  may have straight or tapered sides. In one example, as illustrated in  FIG. 10E , the indentations  478  have all straight sides such that the sides  476  and  477  are straight, e.g., perpendicular to the plane of the lower surface  474 . In another example, as illustrated in  FIG. 10F , the indentations  478  have all tapered sides such that the sides  476  are steeper or more abrupt than the sides  477  which have more of a gradual change of angle. The sides  477  within the indentations  478  may be tapered to compensate for a thermal gradient across levitating wafer carrier  480 . Alternatively, the indentations  478  may have a combination of straight sides and tapered sides such that the sides  476  are straight and the sides  477  have a taper or the sides  477  are straight and the sides  476  have a taper. 
     Levitating wafer carrier  480  contains a heat flux which extends from the lower surface  474  to the upper surface  472  and to any substrates disposed thereon. The heat flux may be controlled by both the internal pressure and length of the processing system. The profile of levitating wafer carrier  480  may be tapered to compensate the heat loses from other sources. During a process, heat is lost through the edges of levitating wafer carrier  480 , such as the short sides  471  and the long sides  473 . However, the heat lost may be compensated by allowing more heat flux into the edges of levitating wafer carrier  480  by reducing the gap of the channel in the levitation. 
     In another embodiment, wafer carrier track  400  contains levitating wafer carrier  480  disposed on guide path  420 . In some examples, levitating wafer carrier  480  has at least one indentation pocket disposed within a lower surface. In other examples, levitating wafer carrier  480  has at least two indentation pockets disposed within a lower surface. 
       FIGS. 5A-5D  depict isolator assembly  500  for a vapor deposition chamber, such as reactor  100 , according embodiments described herein. In one embodiment, isolator assembly  500  includes body  502  having upper portion  506  and lower portion  504 , and centralized channel  516  extending through upper portion  506  and lower portion  504  of body  502 . Upper portion  506  contains upper surface  507 . Centralized channel  516  extends between inner surfaces  509  of body  502 , and parallel to central axis  501  extending through body  502 . Diffusion plate  530  contains a plurality of gas holes  532  and is disposed within centralized channel  516 . In one example, diffusion plate  530  is disposed on a flange or ledge  510 . In another example, isolator assembly  500  does not contain diffusion plate  530  disposed therein. 
     Isolator assembly  500  further contains upper tube plate  540  having a plurality of gas holes  542  and disposed within centralized channel  516  below diffusion plate  530 . Isolator assembly  500  also contains lower tube plate  550  having a plurality of gas holes  552  and disposed within centralized channel  516  below upper tube plate  540 . A plurality of gas tubes  580  extend from upper tube plate  540  to lower tube plate  550 , wherein each tube is coupled to and in fluid communication with an individual hole from the plurality of gas holes  542  and an individual hole from plurality of gas holes  552 . Each of the gas tubes  580  extends parallel or substantially parallel to each other as well as to central axis  501  in many embodiments described herein. In an alternative embodiment, not shown, each of the gas tubes  580  may extend at a predetermined angle relative to central axis  501 , such as within a range from about 1° to about 15° or greater. 
     Isolator assembly  500  may be used to disperse gases, such as purge gases, precursor gases, and/or carrier gases, by providing a flow path through inlet port  522  and into cavities  538 ,  548 , and  558 . Cavity  538  is formed between upper plate  520  and diffusion plate  530  within centralized channel  516 . Cavity  548  is formed between diffusion plate  530  and upper tube plate  540  within centralized channel  516 . Cavity  558  is formed between upper tube plate  540  and lower tube plate  550  within centralized channel  516 . 
     In another embodiment, isolator assembly  500  includes body  502  containing upper portion  506  and lower portion  504 , wherein upper portion  506  contains a flange extending over lower portion  504 , centralized channel  516  extending through upper portion  506  and lower portion  504  of body  502 , between inner surfaces  509  of body  502 , and parallel to central axis  501  extending through body  502 , diffusion plate  530  containing a plurality of gas holes  532  and disposed within centralized channel  516 , upper tube plate  540  containing a plurality of gas holes  542  and disposed within centralized channel  516  below diffusion plate  530 , lower tube plate  550  containing a plurality of gas holes  552  and disposed within centralized channel  516  below upper tube plate  540 , and plurality of gas tubes  580  extending from upper tube plate  540  to lower tube plate  550 , wherein each tube is coupled to and in fluid communication with an individual hole from plurality of gas holes  542  and an individual hole from plurality of gas holes  552 . 
     In another embodiment, isolator assembly  500  includes body  502  containing upper portion  506  and lower portion  504 , wherein upper portion  506  adjacently extends from central axis  501  of body  502  further than lower portion  504  and lower portion  504  extends parallel to central axis  501  further than upper portion  506 , centralized channel  516  extending through upper portion  506  and lower portion  504  of body  502 , between inner surfaces  509  of body  502 , and parallel to central axis  501 , diffusion plate  530  containing a plurality of gas holes  532  and disposed within centralized channel  516 , upper tube plate  540  containing a plurality of gas holes  542  and disposed within centralized channel  516  below diffusion plate  530 , lower tube plate  550  containing a plurality of gas holes  552  and disposed within centralized channel  516  below upper tube plate  540 , and plurality of gas tubes  580  extending from upper tube plate  540  to lower tube plate  550 , wherein each tube is coupled to and in fluid communication with an individual hole from plurality of gas holes  542  and an individual hole from plurality of gas holes  552 . 
     In another embodiment, isolator assembly  500  includes body  502  containing upper portion  506  and lower portion  504 , centralized channel  516  extending through upper portion  506  and lower portion  504  of body  502 , between inner surfaces  509  of body  502 , and parallel to central axis  501  extending through body  502 , diffusion plate  530  containing a plurality of gas holes  532  and disposed within centralized channel  516 , upper tube plate  540  containing a plurality of gas holes  542  and disposed within centralized channel  516  below diffusion plate  530 , and lower tube plate  550  containing a plurality of gas holes  552  and disposed within centralized channel  516  below upper tube plate  540 . 
     In another embodiment, isolator assembly  500  includes body  502  containing upper portion  506  and lower portion  504 , centralized channel  516  extending through upper portion  506  and lower portion  504  of body  502 , between inner surfaces  509  of body  502 , and parallel to central axis  501  extending through body  502 , upper tube plate  540  containing a plurality of gas holes  532  and disposed within centralized channel  516  below diffusion plate  530 , lower tube plate  550  containing a plurality of gas holes  542  and disposed within centralized channel  516  below upper tube plate  540 , and plurality of gas tubes  580  extending from upper tube plate  540  to lower tube plate  550 , wherein each tube is coupled to and in fluid communication with an individual hole from plurality of gas holes  532  and an individual hole from plurality of gas holes  542 . 
     In some embodiments, isolator assembly  500  is a modular showerhead assembly. Upper portion  506  and lower portion  504  of body  502  may independently contain a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. In one example, upper portion  506  and lower portion  504  of body  502  each independently contains stainless steel or alloys thereof. 
     In one embodiment, isolator assembly  500  contains gaseous inlet  560  disposed on upper portion  506  of body  502 . Upper plate  520  may be disposed on an upper surface of upper portion  506  of body  502  and gaseous inlet  560  may be disposed on the plate. The plate may contain a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. In some examples, the plate has inlet port  522  extending therethrough. Gaseous inlet  560  has inlet tube  564  extending through inlet port  522 . Inlet nozzle  562  may be coupled to one end of inlet tube  564  and disposed above the plate. In another example, the upper surface of upper portion  506  of the showerhead body has groove  508  which encompasses centralized channel  516 . An O-ring may be disposed within groove  508 . Diffusion plate  530  may be disposed on a ledge or a flange protruding from side surfaces of body  502  within centralized channel  516 . 
     In one embodiment, plurality of gas tubes  580  may have tubes numbering within a range from about 500 tubes to about 1,500 tubes, preferably, from about 700 tubes to about 1,200 tubes, and more preferably, from about 800 tubes to about 1,000 tubes, for example, about 900 tubes. In some examples, each tube may have a length within a range from about 0.5 cm to about 2 cm, preferably, from about 0.8 cm to about 1.2 cm, for example, about 1 cm. In other examples, each tube may have a diameter within a range from about 0.005 inches to about 0.05 inches, preferably, from about 0.01 inches to about 0.03 inches. In some examples, the tubes are hypodermic needles. The tubes may contain or be made from a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. 
     In one embodiment, each hole of plurality of gas holes  532  on diffusion plate  530  has a larger diameter than each hole of plurality of gas holes  542  on upper tube plate  540 . Further, each hole of plurality of gas holes  532  on diffusion plate  530  has a larger diameter than each hole of plurality of gas holes  552  on the lower diffusion plate. Also, each hole of plurality of gas holes  542  on upper tube plate  540  has the same diameter or substantially the same diameter as each hole of plurality of gas holes  552  on lower tube plate  550 . 
     In one embodiment, diffusion plate  530  may contain or be made from a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. Diffusion plate  530  may contain holes numbering within a range from about 20 holes to about 200 holes, preferably, from about 25 holes to about 55 holes, and more preferably, from about 40 holes to about 60 holes. Each hole of diffusion plate  530  may have a diameter within a range from about 0.005 inches to about 0.05 inches, preferably, from about 0.01 inches to about 0.03 inches. In another embodiment, upper tube plate  540  and/or lower tube plate  550  may independently contain or be independently made from a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. Upper tube plate  540  and/or lower tube plate  550  may independently have from about 500 holes to about 1,500 holes, preferably, from about 700 holes to about 1,200 holes, and more preferably, from about 800 holes to about 1,000 holes. Each hole of upper tube plate  540  and/or lower tube plate  550  may independently have a diameter within a range from about 0.005 inches to about 0.05 inches, preferably, from about 0.01 inches to about 0.03 inches. In another embodiment, isolator assembly  500  may have a gaseous hole density and/or number of tubes within a range from about 10 holes/in 2  (holes per square inch) to about 60 holes/in 2 , preferably, from about 15 holes/in 2  to about 45 holes/in 2 , and more preferably, from about 20 holes/in 2  to about 36 holes/in 2 . 
     In one example, the upper surface of upper portion  506  of body  502  of isolator assembly  500  is a metallic plate. In other examples, isolator assembly  500  may have a rectangular geometry or a square geometry. In another embodiment, body  502  of isolator assembly  500  further contains a temperature regulation system. The temperature regulation system, such as temperature regulation system  190 , may contain fluid passageway  518  extending within body  502 , and may have inlet  514   a  and outlet  514   b  coupled to and in fluid communication with fluid passageway  518 . Inlet  514   a  and outlet  514   b  may be independently coupled to and in fluid communication with a liquid reservoir or at least one heat exchanger, such as heat exchangers  180   a ,  180   b , or  180   c  within temperature regulation system  190 , as depicted in  FIG. 1F . 
       FIG. 6  depicts heating lamp assembly  600 , which may be utilized to heat wafers or substrates, as well as wafer carriers or substrate supports within a vapor deposition reactor system, as described in embodiments herein. In one embodiment, heating lamp assembly  600  is provided which includes lamp housing  610  disposed on upper surface  606  of support base  602  and containing first lamp holder  620   a  and second lamp holder  620   b , a plurality of lamps  624  extending from first lamp holder  620   a  to second lamp holder  620   b , wherein each lamp  624  has a split filament or a non-split filament, and reflector  650  disposed on upper surface  606  of support base  602  is disposed between first lamp holder  620   a  and second lamp holder  620   b.    
     In another embodiment, heating lamp assembly  600  includes lamp housing  610  disposed on upper surface  606  of support base  602  and containing first lamp holder  620   a  and second lamp holder  620   b , a first plurality of lamps  624  extending from first lamp holder  620   a  to second lamp holder  620   b , wherein each lamp of the first plurality has a split filament, a second plurality of lamps  624  extending from first lamp holder  620   a  to second lamp holder  620   b , wherein each lamp of the second plurality has a non-split filament, and reflector  650  disposed on upper surface  606  of support base  602  between first lamp holder  620   a  and second lamp holder  620   b.    
     In another embodiment, heating lamp assembly  600  includes lamp housing  610  disposed on upper surface  606  of support base  602  and containing first lamp holder  620   a  and second lamp holder  620   b , a first plurality of lamps  624  extending from first lamp holder  620   a  to second lamp holder  620   b , wherein each lamp of the first plurality has a split filament, a second plurality of lamps  624  extending from first lamp holder  620   a  to second lamp holder  620   b , wherein each lamp of the second plurality has a non-split filament, and the first plurality of lamps  624  are sequentially or alternately disposed between the second plurality of lamps  624  while extending between the first and second lamp holders. Also, reflector  650  may be disposed on upper surface  606  of support base  602  between first lamp holder  620   a  and second lamp holder  620   b.    
     In another embodiment, heating lamp assembly  600  includes lamp housing  610  disposed on upper surface  606  of support base  602  and containing first lamp holder  620   a  and second lamp holder  620   b , a plurality of lamps  624  extending from first lamp holder  620   a  to second lamp holder  620   b , wherein the plurality of lamps  624  contain a first group of lamps and a second group of lamps sequentially or alternately disposed between each other, each lamp of the first group of lamps contains a split filament, and each lamp of the second group of lamps contains a non-split filament, and reflector  650  disposed on upper surface  606  of support base  602  between first lamp holder  620   a  and second lamp holder  620   b.    
     In another embodiment, heating lamp assembly  600  includes lamp housing  610  disposed on upper surface  606  of support base  602  and containing first lamp holder  620   a  and second lamp holder  620   b , a plurality of posts  622  disposed on first lamp holder  620   a  and second lamp holder  620   b , a plurality of lamps  624  extending from first lamp holder  620   a  to second lamp holder  620   b , wherein each lamp has a split filament or a non-split filament, and reflector  650  disposed on upper surface  606  of support base  602  between first lamp holder  620   a  and second lamp holder  620   b.    
     In another embodiment, heating lamp assembly  600  includes lamp housing  610  disposed on upper surface  606  of support base  602  and containing first lamp holder  620   a  and second lamp holder  620   b , a plurality of posts  622  disposed on first lamp holder  620   a  and second lamp holder  620   b , a plurality of lamps  624  extending from first lamp holder  620   a  to second lamp holder  620   b , wherein each lamp has a split filament or a non-split filament, and each lamp has a first end disposed between two posts  622  on first lamp holder  620   a  and a second end disposed between two posts  622  on second lamp holder  620   b , and reflector  650  disposed on upper surface  606  of support base  602  between first lamp holder  620   a  and second lamp holder  620   b.    
     In another embodiment, heating lamp assembly  600  includes lamp housing  610  disposed on upper surface  606  of support base  602  and containing first lamp holder  620   a  and second lamp holder  620   b , a plurality of posts  622  disposed on first lamp holder  620   a  and second lamp holder  620   b , a plurality of lamps  624  extending from first lamp holder  620   a  to second lamp holder  620   b , wherein each lamp has a first end disposed between two posts  622  on first lamp holder  620   a  and a second end disposed between two posts  622  on second lamp holder  620   b , and reflector  650  disposed on upper surface  606  of support base  602  between first lamp holder  620   a  and second lamp holder  620   b.    
     In another embodiment, heating lamp assembly  600  includes lamp housing  610  disposed on upper surface  606  of support base  602  and containing first lamp holder  620   a  and second lamp holder  620   b , a plurality of posts  622  disposed on first lamp holder  620   a  and second lamp holder  620   b , a plurality of lamps  624  extending from first lamp holder  620   a  to second lamp holder  620   b , and reflector  650  disposed on upper surface  606  of support base  602  between first lamp holder  620   a  and second lamp holder  620   b.    
     In another embodiment, heating lamp assembly  600  for a vapor deposition reactor system is provided which includes lamp housing  610  disposed on upper surface  606  of support base  602  and containing first lamp holder  620   a  and second lamp holder  620   b , a plurality of lamps  624  extending from first lamp holder  620   a  to second lamp holder  620   b , and reflector  650  disposed on upper surface  606  of support base  602  between first lamp holder  620   a  and second lamp holder  620   b.    
     In one embodiment, heating lamp assembly  600  contains reflector  650  and/or the upper surface of reflector  650  contains a reflective metal, such as gold, silver, copper, aluminum, nickel, chromium, alloys thereof, or combinations thereof. In many examples, reflector  650  and/or the upper surface of reflector  650  contains gold or a gold alloy. The lower surface of wafer carrier track  400  may be exposed to radiation emitted from lamps  624  within heating lamp assembly  600  and reflected from reflector  650 , the upper surface of reflector  650 , and/or each mirror  652 . The emitted radiation is absorbed by wafer carrier track  400 , levitating wafer carrier  460 , and wafers  90  within reactor  100 . In some embodiments of processes described herein, wafer carrier track  400 , levitating wafer carrier  460 , and/or wafers  90  may each be independently heated by the emitted radiation to a temperature within a range from about 250° C. to about 350° C., preferably, from about 275° C. to about 325° C., preferably, from about 290° C. to about 310° C., such as about 300° C. 
     Heating lamp assembly  600  may contain at least one mirror  652  which extends along upper surface  606  of support base  602  and may be perpendicular or substantially perpendicular to upper surface  606  of support base  602 . In some examples, mirror  652  may be the inner side surfaces of each lamp holder  620   a  or  620   b  having a reflective coating deposited or otherwise disposed thereon. In other examples, mirror  652  may be a prefabricated or modular mirror or reflective material which is attached or adhered to the inner side surfaces of each lamp holder  620   a  or  620   b . The at least one mirror  652  is generally positioned to face towards reflector  650  at an angle of about 90° relative to the plane of surface  606 . Preferably, in another embodiment described herein, heating lamp assembly  600  contains two mirrors  652  extending along upper surface  606  of support base  602 . Both mirrors may be perpendicular or substantially perpendicular to upper surface  606  of support base  602  and both mirrors  652  may face towards each other with reflector  650  therebetween. Each of the two mirrors  652  faces towards reflector  650  at an angle of about 90° relative to the plane of surface  606 . Each mirror and/or the upper surface of each mirror  652  contains a reflective metal, such as gold, silver, copper, aluminum, nickel, chromium, alloys thereof, or combinations thereof. In many examples, each mirror  652  and/or the upper surface of each mirror  652  contains gold or a gold alloy. 
     In alternative embodiments, not shown, each mirror  652  may be positioned to slightly face away from reflector  650  at an angle of greater than 90° relative to the plane of surface  606 , such at an angle within a range from greater than 90° to about 135°. Mirror  652  positioned at an angle of greater than 90° may be utilized to direct energy towards wafer carrier track  400 , levitating wafer carrier  460 , or other parts or surfaces within reactor  100 . In alternative embodiments, heating lamp assembly  600  may contain three or more mirrors  652  along upper surface  606  of support base  602 . 
     The plurality of lamps  624  within heating lamp assembly  600  may number from about 10 lamps to about 100 lamps, preferably, from about 20 lamps to about 50 lamps, and more preferably, from about 30 lamps to about 40 lamps. In one example, heating lamp assembly  600  contains about 34 lamps. Embodiments provide that each lamp may be in electrical contact with a power source, an independent switch, and a controller. The controller may be used to independently control power to each lamp. 
     In other embodiments, support base  602  and each lamp holder  620   a  or  620   b  within heating lamp assembly  600  may independently contain or be made from a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. In some examples, first lamp holder  620   a  or second lamp holder  620   b  may independently contain or be made from stainless steel or alloys thereof. First lamp holder  620   a  or second lamp holder  620   b  independently may have a cooling coefficient within a range from about 2,000 W/m 2 -K to about 3,000 W/m 2 -K, preferably, from about 2,300 W/m 2 -K to about 2,700 W/m 2 -K. In one example, the cooling coefficient is about 2,500 W/m 2 -K. In other embodiments, first lamp holder  620   a  and second lamp holder  620   b  each have a thickness within a range from about 0.001 inches to about 0.1 inches. 
       FIG. 10A  depicts a non-split filament lamp  670  and  FIG. 10B  depicts a split filament lamp  680  according to multiple embodiments described herein. Non-split filament lamp  670  contains bulb  672  and non-split filament  674 , while split filament lamp  680  contains bulb  682  and non-split filament  684 . The plurality of lamps  624 , as described throughout embodiments herein, generally contain non-split filament lamps  670 , split filament lamps  680 , or mixtures of non-split filament lamps  670  and split filament lamps  680 . 
       FIGS. 11A-11F  depict different pluralities of lamps which may be lamps  624  and utilized to adjust a heat profile on a wafer carrier track, such as wafer carrier track  400 , a wafer carrier or substrate support, such as levitating wafer carrier  480 , and/or a wafer or a substrate, such as wafers  90 , within a vapor deposition reactor, such as reactor  100 , as described in embodiments herein. In one embodiment,  FIG. 11A  illustrates a plurality of lamps containing all non-split filament lamps  670  and  FIG. 11B  illustrates a plurality of lamps containing all split filament lamps  680 . In another embodiment,  FIG. 11C  illustrates a plurality of lamps sequentially or alternatively containing non-split filament lamps  670  and split filament lamps  680 . In other embodiments,  FIG. 11D  illustrates a plurality of lamps containing a split filament lamp  680  between every two non-split filament lamps  670 , while  FIG. 11E  illustrates a plurality of lamps containing a non-split filament lamp  670  between every two split filament lamps  680 .  FIG. 11F  illustrates a plurality of lamps sequentially or alternatively containing non-split filament lamps  670  and split filament lamps  680 , however, each lamp is spaced further apart from each other than the lamps in  FIGS. 11A-11E . 
     In other embodiments, a method for heating a substrate or a substrate susceptor, such as levitating wafer carrier  480 , within a vapor deposition reactor system, such as reactor  100 , by heating lamp assembly  600  is provided which includes exposing a lower surface of a substrate susceptor to energy emitted from heating lamp assembly  600 , and heating the substrate susceptor to a predetermined temperature, wherein heating lamp assembly  600  contains lamp housing  610  disposed on upper surface  606  of support base  602  and containing at least one lamp holder  620   a  or  620   b , a plurality of lamps  624  extending from at least one of the lamp holders, and reflector  650  disposed on upper surface  606  of support base  602 , next to the lamp holder, and below the lamps. 
     Embodiments of the method further provide that heating lamp assembly  600  contains lamps which have split filament lamp  680 , a non-split filament, or a mixture of lamps which contain either split or non-split filaments. In one embodiment, each of the lamps has split filament lamp  680 . Split filament lamp  680  may have a center between a first end and a second end. The first and second ends of split filament lamps  680  may be maintained warmer than the centers of split filament lamps  680 . Therefore, outer edges of the substrate susceptor may be maintained warmer than a center point of the substrate susceptor. 
     In another embodiment, each of the lamps has non-split filament lamp  670 . Non-split filament lamp  670  may have a center between a first end and a second end. The centers of non-split filament lamps  670  may be maintained warmer than the first and second ends of non-split filament lamps  670 . Therefore, a center point of the substrate susceptor may be maintained warmer than the outer edges of the substrate susceptor. 
     In another embodiment, the plurality of lamps  624  have split filament lamps and non-split filament lamps. In one embodiment, split filament lamps  680  and non-split filament lamps  670  are sequentially disposed between each other. Each lamp may independently be in electric contact to a power source and a controller. The method further includes independently adjusting the amount of electricity flowing to each lamp. In one example, split filament lamp  680  may have a center between a first end and a second end. The first and second ends of split filament lamps  680  may be maintained warmer than the centers of split filament lamps  680 . Therefore, the outer edges of the substrate susceptor may be maintained warmer than a center point of the substrate susceptor. In another example, non-split filament lamp  670  may have a center between a first end and a second end. The centers of non-split filament lamps  670  may be maintained warmer than the first and second ends of non-split filament lamps  670 . Therefore, the center point of the substrate susceptor may be maintained warmer than the outer edges of the substrate susceptor. 
     In various embodiments, the method provides that the substrate susceptor may be a substrate carrier or a wafer carrier. Lamp housing  610  may have first lamp holder  620   a  and second lamp holder  620   b . First lamp holder  620   a  and second lamp holder  620   b  may be parallel or substantially parallel to each other. In one example, reflector  650  may be disposed between first lamp holder  620   a  and second lamp holder  620   b . First lamp holder  620   a  and second lamp holder  620   b  each have a thickness within a range from about 0.001 inches to about 0.1 inches. The predetermined thickness of the lamp holders helps maintain a constant temperature of the lamp holders. Therefore, first lamp holder  620   a  and second lamp holder  620   b  may each independently be maintained at a temperature within a range from about 275° C. to about 375° C., preferably, from about 300° C. to about 350° C. 
       FIGS. 7A-7D  depict showerhead assembly  700  for a vapor deposition chamber, such as reactor  100 , according embodiments described herein. In one embodiment, showerhead assembly  700  includes body  702  having upper portion  706  and lower portion  704 , and centralized channel  716  extending through upper portion  706  and lower portion  704  of body  702 . Upper portion  706  contains upper surface  707 . Centralized channel  716  extends between inner surfaces  709  of body  702 , and parallel to central axis  701  extending through body  702 . Diffusion plate  730  contains a plurality of gas holes  732  and is disposed within centralized channel  716 . In one example, diffusion plate  730  is disposed on a flange or ledge  710 . In another example, showerhead assembly  700  does not contain optional diffusion plate  730  disposed therein. 
     Showerhead assembly  700  further contains upper tube plate  740  having a plurality of gas holes  742  and disposed within centralized channel  716  below diffusion plate  730 . Showerhead assembly  700  also contains lower tube plate  750  having a plurality of gas holes  752  and disposed within centralized channel  716  below upper tube plate  740 . A plurality of gas tubes  780  extend from upper tube plate  740  to lower tube plate  750 , wherein each tube is coupled to and in fluid communication with an individual hole from the plurality of gas holes  742  and an individual hole from plurality of gas holes  752 . Each of the gas tubes  780  extends parallel or substantially parallel to each other as well as to central axis  701  in many embodiments described herein. In an alternative embodiment, not shown, each of the gas tubes  780  may extend at a predetermined angle relative to central axis  701 , such as within a range from about 1° to about 15° or greater. 
     Showerhead assembly  700  may be used to disperse gases, such as purge gases, precursor gases, and/or carrier gases, by providing a flow path through inlet port  722  and into cavities  738 ,  748 , and  758 . Cavity  738  is formed between upper plate  720  and diffusion plate  730  within centralized channel  716 . Cavity  748  is formed between diffusion plate  730  and upper tube plate  740  within centralized channel  716 . Cavity  758  is formed between upper tube plate  740  and lower tube plate  750  within centralized channel  716 . 
     In another embodiment, showerhead assembly  700  includes body  702  containing upper portion  706  and lower portion  704 , wherein upper portion  706  contains a flange extending over lower portion  704 , centralized channel  716  extending through upper portion  706  and lower portion  704  of body  702 , between inner surfaces  709  of body  702 , and parallel to central axis  701  extending through body  702 , diffusion plate  730  containing a plurality of gas holes  732  and disposed within centralized channel  716 , upper tube plate  740  containing a plurality of gas holes  742  and disposed within centralized channel  716  below diffusion plate  730 , lower tube plate  750  containing a plurality of gas holes  752  and disposed within centralized channel  716  below upper tube plate  740 , and plurality of gas tubes  780  extending from upper tube plate  740  to lower tube plate  750 , wherein each tube is coupled to and in fluid communication with an individual hole from plurality of gas holes  742  and an individual hole from plurality of gas holes  752 . 
     In another embodiment, showerhead assembly  700  includes body  702  containing upper portion  706  and lower portion  704 , wherein upper portion  706  adjacently extends from central axis  701  of body  702  further than lower portion  704  and lower portion  704  extends parallel to central axis  701  further than upper portion  706 , centralized channel  716  extending through upper portion  706  and lower portion  704  of body  702 , between inner surfaces  709  of body  702 , and parallel to central axis  701 , diffusion plate  730  containing a plurality of gas holes  732  and disposed within centralized channel  716 , upper tube plate  740  containing a plurality of gas holes  742  and disposed within centralized channel  716  below diffusion plate  730 , lower tube plate  750  containing a plurality of gas holes  752  and disposed within centralized channel  716  below upper tube plate  740 , and plurality of gas tubes  780  extending from upper tube plate  740  to lower tube plate  750 , wherein each tube is coupled to and in fluid communication with an individual hole from plurality of gas holes  742  and an individual hole from plurality of gas holes  752 . 
     In another embodiment, showerhead assembly  700  includes body  702  containing upper portion  706  and lower portion  704 , centralized channel  716  extending through upper portion  706  and lower portion  704  of body  702 , between inner surfaces  709  of body  702 , and parallel to central axis  701  extending through body  702 , diffusion plate  730  containing a plurality of gas holes  732  and disposed within centralized channel  716 , upper tube plate  740  containing a plurality of gas holes  742  and disposed within centralized channel  716  below diffusion plate  730 , and lower tube plate  750  containing a plurality of gas holes  752  and disposed within centralized channel  716  below upper tube plate  740 . 
     In another embodiment, showerhead assembly  700  includes body  702  containing upper portion  706  and lower portion  704 , centralized channel  716  extending through upper portion  706  and lower portion  704  of body  702 , between inner surfaces  709  of body  702 , and parallel to central axis  701  extending through body  702 , upper tube plate  740  containing a plurality of gas holes  732  and disposed within centralized channel  716  below diffusion plate  730 , lower tube plate  750  containing a plurality of gas holes  742  and disposed within centralized channel  716  below upper tube plate  740 , and plurality of gas tubes  780  extending from upper tube plate  740  to lower tube plate  750 , wherein each tube is coupled to and in fluid communication with an individual hole from plurality of gas holes  732  and an individual hole from plurality of gas holes  742 . 
     In some embodiments, showerhead assembly  700  is a modular showerhead assembly. Upper portion  706  and lower portion  704  of body  702  may independently contain a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. In one example, upper portion  706  and lower portion  704  of body  702  each independently contains stainless steel or alloys thereof. 
     In one embodiment, showerhead assembly  700  contains gaseous inlet  760  disposed on upper portion  706  of body  702 . Upper plate  720  may be disposed on an upper surface of upper portion  706  of body  702  and gaseous inlet  760  may be disposed on the plate. The plate may contain a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. In some examples, the plate has inlet port  722  extending therethrough. Gaseous inlet  760  has inlet tube  764  extending through inlet port  722 . Inlet nozzle  762  may be coupled to one end of inlet tube  764  and disposed above the plate. In another example, the upper surface of upper portion  706  of the showerhead body has groove  708  which encompasses centralized channel  716 . An O-ring may be disposed within groove  708 . Diffusion plate  730  may be disposed on a ledge or a flange protruding from side surfaces of body  702  within centralized channel  716 . 
     In one embodiment, plurality of gas tubes  780  may have tubes numbering within a range from about 500 tubes to about 1,500 tubes, preferably, from about 700 tubes to about 1,200 tubes, and more preferably, from about 800 tubes to about 1,000 tubes, for example, about 900 tubes. In some examples, each tube may have a length within a range from about 0.5 cm to about 2 cm, preferably, from about 0.8 cm to about 1.2 cm, for example, about 1 cm. In other examples, each tube may have a diameter within a range from about 0.005 inches to about 0.05 inches, preferably, from about 0.01 inches to about 0.03 inches. In some examples, the tubes are hypodermic needles. The tubes may contain or be made from a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. 
     In one embodiment, each hole of plurality of gas holes  732  on diffusion plate  730  has a larger diameter than each hole of plurality of gas holes  742  on upper tube plate  740 . Further, each hole of plurality of gas holes  732  on diffusion plate  730  has a larger diameter than each hole of plurality of gas holes  752  on the lower diffusion plate. Also, each hole of plurality of gas holes  742  on upper tube plate  740  has the same diameter or substantially the same diameter as each hole of plurality of gas holes  752  on lower tube plate  750 . 
     In one embodiment, diffusion plate  730  may contain or be made from a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. Diffusion plate  730  may contain holes numbering within a range from about 20 holes to about 200 holes, preferably, from about 25 holes to about 75 holes, and more preferably, from about 40 holes to about 60 holes. Each hole of diffusion plate  730  may have a diameter within a range from about 0.005 inches to about 0.05 inches, preferably, from about 0.01 inches to about 0.03 inches. In another embodiment, upper tube plate  740  and/or lower tube plate  750  may independently contain or be independently made from a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. Upper tube plate  740  and/or lower tube plate  750  may independently have from about 500 holes to about 1,500 holes, preferably, from about 700 holes to about 1,200 holes, and more preferably, from about 800 holes to about 1,000 holes. Each hole of upper tube plate  740  and/or lower tube plate  750  may independently have a diameter within a range from about 0.005 inches to about 0.05 inches, preferably, from about 0.01 inches to about 0.03 inches. In another embodiment, showerhead assembly  700  may have a gaseous hole density and/or number of tubes within a range from about 10 holes/in 2  (holes per square inch) to about 60 holes/in 2 , preferably, from about 15 holes/in 2  to about 45 holes/in 2 , and more preferably, from about 20 holes/in 2  to about 36 holes/in 2 . 
     In one example, the upper surface of upper portion  706  of body  702  of showerhead assembly  700  is a metallic plate. In other examples, showerhead assembly  700  may have a rectangular geometry or a square geometry. In another embodiment, body  702  of showerhead assembly  700  further contains a temperature regulation system. The temperature regulation system, such as temperature regulation system  190 , may contain liquid or fluid passageway  718  extending within body  702 , and may have inlet  714   a  and outlet  714   b  coupled to and in fluid communication with fluid passageway  718 . Inlet  714   a  and outlet  714   b  may be independently coupled to and in fluid communication with a liquid reservoir or at least one heat exchanger, such as heat exchangers  180   a ,  180   b , or  180   c  within temperature regulation system  190 , as depicted in  FIG. 1F . 
       FIGS. 8A-8D  depict exhaust assembly  800  for a vapor deposition chamber, such as reactor  100 , according embodiments described herein. In one embodiment, exhaust assembly  800  includes body  802  having upper portion  806  and lower portion  804 , and centralized channel  816  extending through upper portion  806  and lower portion  804  of body  802 . Upper portion  806  contains upper surface  807 . Centralized channel  816  extends between inner surfaces  809  of body  802 , and parallel to central axis  801  extending through body  802 . Diffusion plate  830  contains a plurality of gas holes  832  and is disposed within centralized channel  816 . In one example, diffusion plate  830  is disposed on a flange or ledge  810 . In another example, exhaust assembly  800  does not contain optional diffusion plate  830  disposed therein. 
     Exhaust assembly  800  further contains upper tube plate  840  having a plurality of gas holes  842  and disposed within centralized channel  816  below diffusion plate  830 . Exhaust assembly  800  also contains lower tube plate  850  having a plurality of gas holes  854  and disposed within centralized channel  816  below upper tube plate  840 . A plurality of exhaust tubes  880  extend from upper tube plate  840  to lower tube plate  850 , wherein each tube is coupled to and in fluid communication with an individual hole from the plurality of gas holes  842  and an individual hole from plurality of gas holes  854 . Each of the exhaust tubes  880  extends parallel or substantially parallel to each other as well as to central axis  801  in many embodiments described herein. In an alternative embodiment, each of the exhaust tubes  880  may extend at a predetermined angle relative to central axis  801 , such as within a range from about 1° to about 15° or greater. 
     Exhaust assembly  800  pulls a vacuum or reduces internal pressure though exhaust port  822  and cavities  838 ,  848 , and  858 . Cavity  838  is formed between upper plate  820  and diffusion plate  830  within centralized channel  816 . Cavity  848  is formed between diffusion plate  830  and upper tube plate  840  within centralized channel  816 . Cavity  858  is formed between upper tube plate  840  and lower tube plate  850  within centralized channel  816 . 
     In another embodiment, exhaust assembly  800  includes body  802  containing upper portion  806  and lower portion  804 , wherein upper portion  806  contains a flange extending over lower portion  804 , centralized channel  816  extending through upper portion  806  and lower portion  804  of body  802 , between inner surfaces  809  of body  802 , and parallel to central axis  801  extending through body  802 , diffusion plate  830  containing a plurality of gas holes  832  and disposed within centralized channel  816 , upper tube plate  840  containing a plurality of gas holes  842  and disposed within centralized channel  816  below diffusion plate  830 , lower tube plate  850  containing a plurality of gas holes  854  and disposed within centralized channel  816  below upper tube plate  840 , and plurality of exhaust tubes  880  extending from upper tube plate  840  to lower tube plate  850 , wherein each tube is coupled to and in fluid communication with an individual hole from plurality of gas holes  842  and an individual hole from plurality of gas holes  854 . 
     In another embodiment, exhaust assembly  800  includes body  802  containing upper portion  806  and lower portion  804 , wherein upper portion  806  adjacently extends from central axis  801  of body  802  further than lower portion  804  and lower portion  804  extends parallel to central axis  801  further than upper portion  806 , centralized channel  816  extending through upper portion  806  and lower portion  804  of body  802 , between inner surfaces  809  of body  802 , and parallel to central axis  801 , diffusion plate  830  containing a plurality of gas holes  832  and disposed within centralized channel  816 , upper tube plate  840  containing a plurality of gas holes  842  and disposed within centralized channel  816  below diffusion plate  830 , lower tube plate  850  containing a plurality of gas holes  854  and disposed within centralized channel  816  below upper tube plate  840 , and plurality of exhaust tubes  880  extending from upper tube plate  840  to lower tube plate  850 , wherein each tube is coupled to and in fluid communication with an individual hole from plurality of gas holes  842  and an individual hole from plurality of gas holes  854 . 
     In another embodiment, exhaust assembly  800  includes body  802  containing upper portion  806  and lower portion  804 , centralized channel  816  extending through upper portion  806  and lower portion  804  of body  802 , between inner surfaces  809  of body  802 , and parallel to central axis  801  extending through body  802 , diffusion plate  830  containing a plurality of gas holes  832  and disposed within centralized channel  816 , upper tube plate  840  containing a plurality of gas holes  842  and disposed within centralized channel  816  below diffusion plate  830 , and lower tube plate  850  containing a plurality of gas holes  854  and disposed within centralized channel  816  below upper tube plate  840 . 
     In another embodiment, exhaust assembly  800  includes body  802  containing upper portion  806  and lower portion  804 , centralized channel  816  extending through upper portion  806  and lower portion  804  of body  802 , between inner surfaces  809  of body  802 , and parallel to central axis  801  extending through body  802 , upper tube plate  840  containing a plurality of gas holes  832  and disposed within centralized channel  816  below diffusion plate  830 , lower tube plate  850  containing a plurality of gas holes  842  and disposed within centralized channel  816  below upper tube plate  840 , and plurality of exhaust tubes  880  extending from upper tube plate  840  to lower tube plate  850 , wherein each tube is coupled to and in fluid communication with an individual hole from plurality of gas holes  832  and an individual hole from plurality of gas holes  842 . 
     In some embodiments, exhaust assembly  800  is a modular showerhead assembly. Upper portion  806  and lower portion  804  of body  802  may independently contain a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. In one example, upper portion  806  and lower portion  804  of body  802  each independently contains stainless steel or alloys thereof. 
     In one embodiment, exhaust assembly  800  contains exhaust outlet  860  disposed on upper portion  806  of body  802 . Upper plate  820  may be disposed on an upper surface of upper portion  806  of body  802  and exhaust outlet  860  may be disposed on the plate. The plate may contain a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. In some examples, the plate has exhaust port  822  extending therethrough. Exhaust outlet  860  has exhaust outlet tube  864  extending through exhaust port  822 . Exhaust nozzle  862  may be coupled to one end of exhaust outlet tube  864  and disposed above the plate. In another example, the upper surface of upper portion  806  of the showerhead body has groove  808  which encompasses centralized channel  816 . An O-ring may be disposed within groove  808 . Diffusion plate  830  may be disposed on a ledge or a flange protruding from side surfaces of body  802  within centralized channel  816 . 
     In one embodiment, plurality of exhaust tubes  880  may have tubes numbering within a range from about 5 tubes to about 50 tubes, preferably, from about 7 tubes to about 30 tubes, and more preferably, from about 10 tubes to about 20 tubes, for example, about 14 tubes. In some examples, each tube may have a length within a range from about 0.5 cm to about 2 cm, preferably, from about 0.8 cm to about 1.2 cm, for example, about 1 cm. In other examples, each tube may have a diameter within a range from about 0.1 inches to about 0.4 inches, preferably, from about 0.2 inches to about 0.3 inches, for example, about 0.23 inches. In one example, exhaust assembly  800  contains a single row of tubes and holes. 
     In another embodiment, plurality of exhaust tubes  880  may have tubes numbering within a range from about 500 tubes to about 1,500 tubes, preferably, from about 700 tubes to about 1,200 tubes, and more preferably, from about 800 tubes to about 1,000 tubes, for example, about 900 tubes. In some examples, each tube may have a length within a range from about 0.5 cm to about 2 cm, preferably, from about 0.8 cm to about 1.2 cm, for example, about 1 cm. In other examples, each tube may have a diameter within a range from about 0.005 inches to about 0.05 inches, preferably, from about 0.01 inches to about 0.03 inches. 
     In some examples, the tubes are hypodermic needles. The tubes may contain or be made from a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. 
     In one embodiment, each hole of plurality of gas holes  832  on diffusion plate  830  has a larger diameter than each hole of plurality of gas holes  842  on upper tube plate  840 . Further, each hole of plurality of gas holes  832  on diffusion plate  830  has a larger diameter than each hole of plurality of gas holes  854  on the lower diffusion plate. Also, each hole of plurality of gas holes  842  on upper tube plate  840  has the same diameter or substantially the same diameter as each hole of plurality of gas holes  854  on lower tube plate  850 . 
     In one embodiment, diffusion plate  830  may contain or be made from a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. In another embodiment, diffusion plate  830  may contain holes numbering within a range from about 5 holes to about 50 holes, preferably, from about 7 holes to about 30 holes, and more preferably, from about 10 holes to about 20 holes, for example, about 14 holes. Each hole of diffusion plate  830  may have a diameter within a range from about 0.1 inches to about 0.4 inches, preferably, from about 0.2 inches to about 0.3 inches, for example, about 0.23 inches. In one example, diffusion plate  830  contains a single row of holes. In another embodiment, diffusion plate  830  may contain holes numbering within a range from about 20 holes to about 200 holes, preferably, from about 25 holes to about 55 holes, and more preferably, from about 40 holes to about 60 holes. Each hole of diffusion plate  830  may have a diameter within a range from about 0.005 inches to about 0.05 inches, preferably, from about 0.01 inches to about 0.03 inches. 
     In another embodiment, upper tube plate  840  and/or lower tube plate  850  may independently contain or be independently made from a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. In one embodiment, upper tube plate  840  and/or lower tube plate  850  may independently have holes numbering within a range from about 5 holes to about 50 holes, preferably, from about 7 holes to about 30 holes, and more preferably, from about 10 holes to about 20 holes, for example, about 14 holes. Each hole of upper tube plate  840  and/or lower tube plate  850  may independently have a diameter within a range from about 0.1 inches to about 0.4 inches, preferably, from about 0.2 inches to about 0.3 inches, for example, about 0.23 inches. In another embodiment, exhaust assembly  800  may have a gaseous hole density and/or number of tubes within a range from about 5 holes/in 2  (holes per square inch) to about 30 holes/in 2 , preferably, from about 8 holes/in 2  to about 25 holes/in 2 , and more preferably, from about 10 holes/in 2  to about 20 holes/in 2 . 
     In another embodiment, upper tube plate  840  and/or lower tube plate  850  may independently have from about 500 holes to about 1,500 holes, preferably, from about 700 holes to about 1,200 holes, and more preferably, from about 800 holes to about 1,000 holes. Each hole of upper tube plate  840  and/or lower tube plate  850  may independently have a diameter within a range from about 0.005 inches to about 0.05 inches, preferably, from about 0.01 inches to about 0.03 inches. 
     In one example, the upper surface of upper portion  806  of body  802  of exhaust assembly  800  is a metallic plate. In other examples, exhaust assembly  800  may have a rectangular geometry or a square geometry. In another embodiment, body  802  of exhaust assembly  800  further contains a temperature regulation system. The temperature regulation system, such as temperature regulation system  190 , may contain liquid or fluid passageway  818  extending within body  802 , and may have inlet  814   a  and outlet  814   b  coupled to and in fluid communication with fluid passageway  818 . Inlet  814   a  and outlet  814   b  may be independently coupled to and in fluid communication with a liquid reservoir or at least one heat exchanger, such as heat exchangers  180   a ,  180   b , or  180   c  within temperature regulation system  190 , as depicted in  FIG. 1F . 
     In other embodiments, exhaust assembly  800 , which may be utilized in a vapor deposition chamber, has body  802  containing upper portion  806  disposed on lower portion  804 , centralized channel  816  extending through upper portion  806  and lower portion  804  of body  802 , between inner surfaces  809  of body  802 , and parallel to central axis  801  extending through body  802 , exhaust outlet  860  disposed on upper portion  806  of body  802 , diffusion plate  830  containing a plurality of gas holes  832  and disposed within centralized channel  816 , upper tube plate  840  containing a plurality of gas holes  842  and disposed within centralized channel  816  below diffusion plate  830 , lower tube plate  850  containing a plurality of gas holes  852  and disposed within centralized channel  816  below upper tube plate  840 , and plurality of exhaust tubes  880  extending from upper tube plate  840  to lower tube plate  850 , wherein each tube is coupled to and in fluid communication with an individual hole from plurality of gas holes  842  and an individual hole from plurality of gas holes  852 . 
     Exhaust assembly  800  may further contain upper plate  820  disposed on an upper surface of upper portion  806  of body  802 . Exhaust outlet  860  may be disposed on upper plate  820 . Upper plate  820  may contain or be made from a material such as steel, stainless steel, 300 series stainless steel, iron, nickel, chromium, molybdenum, aluminum, alloys thereof, or combinations thereof. Upper plate  820  usually has an exhaust port extending therethrough. Exhaust outlet  860  may have exhaust outlet tube  864  extending through exhaust port  822 . In one example, exhaust nozzle  862  may be coupled to one end of exhaust outlet tube  864  and disposed above upper plate  820 . In another example, the upper surface of upper portion  806  of the exhaust assembly body has groove  808  which encompasses centralized channel  816 . An O-ring may be disposed within groove  808 . Diffusion plate  830  may be disposed on a ledge or a flange protruding from side surfaces of body  802  within centralized channel  816 . 
       FIGS. 9A-9F  depict reactor system  1000 , a CVD system, containing multiple reactors  1100   a ,  1100   b , and  1100   c , as described by embodiments herein. Reactors  1100   a ,  1100   b , and  1100   c  may be the same reactors as reactor  100  or may be a modified derivative of reactor  100 . In one embodiment, reactor  1100   a  is coupled to reactor  1100   b , which is coupled to reactor  1100   c , as illustrated in  FIGS. 9A-9C . One end of reactor  1100   a  is coupled to end cap  1050  at interface  1012 , while the other end of reactor  1100   a  is coupled to one end of reactor  1100   b  at interface  1014 . The other end of reactor  1100   b  is coupled to one end of reactor  1100   c  at interface  1016 , while the other end of reactor  1100   c  is coupled to end plate  1002  at interface  1016 . 
       FIGS. 9D-9F  depicts a close-up view of portions of interface  1018  between reactors  1100   b  and  1100   c . In another embodiment, reactor  1100   b  contains wafer carrier track  1400  which has lower lap joint  1450  and reactor  1100   c  contains wafer carrier track  1400  which has upper lap joint  1440 . 
     Exhaust purge port  1080  may be disposed between wafer carrier track  1400  within reactor  1100   b  and wafer carrier track  1400  within reactor  1100   c . Exhaust purge port  1080  is in fluid communication with passageway  1460 , which extends from exhaust purge port  1080  to below wafer carrier tracks  1400 . Exhaust assembly  1058 , similar to exhaust assembly  800 , is disposed on the reactor lid assembly of reactor  1100   b . Exhaust assembly  1058  may be used to remove gases from exhaust purge port  1080 . Exhaust assembly  1058  contains exhaust outlet  1060 , exhaust nozzle  1062 , and exhaust tube  1064 . 
     In another embodiment, reactor system  1000  may contain additional reactors (not shown) besides reactors  1100   a ,  1100   b , and  1100   c . In one example, a fourth reactor is included in reactor system  1000 . In another example, a fifth reactor is included in reactor system  1000 . In different configurations and embodiments, reactor system  1000  may have 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, or more reactors. In other embodiments, reactors  1100   a ,  1100   b , and  1100   c  or other reactors which are not shown, may contain 1, 2, 3, 4, or more showerhead assemblies in each reactor (not shown). 
     In alternative embodiments described herein, other configurations of reactors  1100   a ,  1100   b , and  1100   c  are provided, but not illustrated in the drawings. In one embodiment, each of the reactors  1100   a ,  1100   b , or  1100   c  may contain three exhaust assemblies separated by two showerhead assemblies so that any of the reactor lid assemblies may sequentially contain a first exhaust assembly, a first showerhead assembly, a second exhaust assembly, a second showerhead assembly, and a third exhaust assembly. In another embodiment, each of the reactors  1100   a ,  1100   b , or  1100   c  may contain three isolator assemblies separated by two showerhead assemblies so that the reactor lid assembly sequentially contain a first isolator assembly, a first showerhead assembly, a second isolator assembly, a second showerhead assembly, and a third isolator assembly. 
     In another embodiment, each of the reactors  1100   a ,  1100   b , or  1100   c  may contain two isolator assemblies and one exhaust assembly separated by two showerhead assemblies so that any of the reactor lid assemblies may sequentially contain a first isolator assembly, a first showerhead assembly, a second isolator assembly, a second showerhead assembly, and a first exhaust assembly. In another example, any of the reactor lid assemblies may sequentially contain a first isolator assembly, a first showerhead assembly, a first exhaust assembly, a second showerhead assembly, and a second isolator assembly. In another example, any of the reactor lid assemblies may sequentially contain a first exhaust assembly, a first showerhead assembly, a first isolator assembly, a second showerhead assembly, and a second isolator assembly. 
     In another embodiment, each of the reactors  1100   a ,  1100   b , or  1100   c  may contain two exhaust assemblies and one isolator assembly separated by two showerhead assemblies so that any of the reactor lid assemblies may sequentially contain a first exhaust assembly, a first showerhead assembly, a second exhaust assembly, a second showerhead assembly, and a first isolator assembly. In another example, any of the reactor lid assemblies may sequentially contain a first exhaust assembly, a first showerhead assembly, a first isolator assembly, a second showerhead assembly, and a second exhaust assembly. In another example, any of the reactor lid assemblies may sequentially contain a first isolator assembly, a first showerhead assembly, a first exhaust assembly, a second showerhead assembly, and a second exhaust assembly. 
     Reactor  100 , reactor system  1000 , and derivatives of these reactors may be used for a variety of CVD, MOCVD, and/or epitaxial deposition processes to form an assortment of materials on wafers or substrates, as described in embodiments herein. In one embodiment, a Group III/V material—which contains at least one element of Group III (e.g., boron, aluminum, gallium, or indium) and at least one element of Group V (e.g., nitrogen, phosphorous, arsenic, or antimony) may be formed or deposited on a wafer. Examples of deposited materials may contain gallium nitride, indium phosphide, gallium indium phosphide, gallium arsenide, aluminum gallium arsenide, derivatives thereof, alloys thereof, multi-layers thereof, or combinations thereof. In some embodiments herein, the deposited materials may be epitaxial materials. The deposited material or epitaxial material may contain one layer, but usually contains multiple layers. In some examples, the epitaxial material contains a layer having gallium arsenide and another layer having aluminum gallium arsenide. In another example, the epitaxial material contains a gallium arsenide buffer layer, an aluminum gallium arsenide passivation layer, and a gallium arsenide active layer. The gallium arsenide buffer layer may have a thickness within a range from about 100 nm to about 500 nm, such as about 300 nm, the aluminum gallium arsenide passivation layer has a thickness within a range from about 10 nm to about 50 nm, such as about 30 nm, and the gallium arsenide active layer has a thickness within a range from about 500 nm to about 2,000 nm, such as about 1,000 nm. In some examples, the epitaxial material further contains a second aluminum gallium arsenide passivation layer. 
     In one embodiment, the process gas used in reactor  100  or reactor system  1000  may contain arsine, argon, helium, nitrogen, hydrogen, or mixtures thereof. In one example, the process gas contains an arsenic precursor, such as arsine. In other embodiments, the first precursor may contain an aluminum precursor, a gallium precursor, an indium precursor, or combinations thereof, and the second precursor may contain a nitrogen precursor, a phosphorus precursor, an arsenic precursor, an antimony precursor or combinations thereof. 
     In one embodiment, the CVD reactor may be configured to supply nitrogen to the reactor to float the substrate along the track of the reactor at the entrance and the exit. A hydrogen/arsine mixture may also be used to float the substrate along the track of the CVD reactor between the exit and entrance. The stages along the track may include an entrance nitrogen isolation zone, a preheat exhaust, a hydrogen/arsine mixture preheat isolation zone, a gallium arsenide deposition zone, a gallium arsenide exhaust, an aluminum gallium arsenide deposition zone, a gallium arsenide N-layer deposition zone, a gallium arsenide P-layer deposition zone, a phosphorous hydrogen arsine isolation zone, a first phosphorous aluminum gallium arsenide deposition zone, a phosphorous aluminum gallium arsenide exhaust, a second phosphorous aluminum gallium arsenide deposition zone, a hydrogen/arsine mixture cool down isolation zone, a cool down exhaust, and an exit nitrogen isolation zone. The temperature of the substrate traveling through the reactor may be increased while passing the entrance isolation zone, or may be maintained while traveling through the zones, or may be decreased while nearing the arsine cool down isolation zone. 
     In another embodiment, the CVD reactor may be configured to supply nitrogen to the reactor to float the substrate along the track of the reactor at the entrance and the exit. A hydrogen/arsine mixture may also be used to float the substrate along the track of the CVD reactor between the exit and entrance. The stages along the track may include an entrance nitrogen isolation zone, a preheat exhaust, a hydrogen/arsine mixture preheat isolation zone, an exhaust, a deposition zone, an exhaust, a hydrogen/arsine mixture cool down isolation zone, a cool down exhaust, and an exit nitrogen isolation zone. The temperature of the substrate traveling through the reactor system may be increased as is passes the entrance isolation zone, may be maintained as is travels through the deposition zone, and may be decreased as it nears the arsine cool down isolation zone. 
     In another embodiment, the CVD reactor may be configured to supply nitrogen to the reactor to float the substrate along the track of the reactor at the entrance and the exit. A hydrogen/arsine mixture may also be used to float the substrate along the track of the CVD reactor between the exit and entrance. The stages along the track may include an entrance nitrogen isolation zone, a preheat exhaust with flow balance restrictor, an active hydrogen/arsine mixture isolation zone, a gallium arsenide deposition zone, an aluminum gallium arsenide deposition zone, a gallium arsenide N-layer deposition zone, a gallium arsenide P-layer deposition zone, a phosphorous aluminum gallium arsenide deposition zone, a cool down exhaust, and an exit nitrogen isolation zone. The temperature of the substrate traveling through the reactor may increase while passing the entrance isolation zone, or may be maintained while traveling through the deposition zones, or may be decreased while nearing the cool down exhaust. 
     In another embodiment, the CVD reactor may be configured to supply nitrogen to the reactor to float the substrate along the track of the reactor at the entrance and the exit. A hydrogen/arsine mixture may also be used to float the substrate along the track of the CVD reactor between the exit and entrance. The stages along the track may include an entrance nitrogen isolation zone, a preheat exhaust with flow balance restrictor, a gallium arsenide deposition zone, an aluminum gallium arsenide deposition zone, a gallium arsenide N-layer deposition zone, a gallium arsenide P-layer deposition zone, a phosphorous aluminum gallium arsenide deposition zone, a cool down exhaust with flow balance restrictor, and an exit nitrogen isolation zone. The temperature of the substrate traveling through the reactor may be increased while passing the entrance isolation zone, or may be maintained while traveling through the deposition zones, or may be decreased while nearing the cool down exhaust. 
       FIG. 17  illustrates a seventh configuration  800 . The CVD reactor may be configured to supply nitrogen to the reactor to float the substrate along the track of the reactor at the entrance and the exit. A hydrogen/arsine mixture may also be used to float the substrate along the track of the CVD reactor between the exit and entrance. The stages along the track may include an entrance nitrogen isolation zone, a preheat exhaust, a deposition zone, a cool down exhaust, and an exit nitrogen isolation zone. The temperature of the substrate traveling through the reactor may be increased while passing the entrance isolation zone, or may be maintained while traveling through the deposition zone, or may be decreased while nearing the cool down exhaust. 
     In one embodiment, the CVD reactor may be configured to epitaxially grow a double hetero-structure containing gallium arsenide materials and aluminum gallium arsenide materials, as well as to epitaxially grow a lateral overgrowth sacrificial layer containing aluminum arsenide materials. In some examples, the gallium arsenide, aluminum gallium arsenide, and aluminum arsenide materials may be deposited at a rate of about 1 μm/min. In some embodiments, the CVD reactor may have a throughput of about 6 wafers per minute to about 10 wafers per minute. 
     In an embodiment, the CVD reactor may be configured to provide a deposition rate of one 10 cm by 10 cm substrate per minute. In one embodiment the CVD reactor may be configured to provide a 300 nm gallium arsenide buffer layer. In one embodiment the CVD reactor may be configured to provide a 30 nm aluminum gallium arsenide passivation layer. In one embodiment the CVD reactor may be configured to provide a 1,000 nm gallium arsenide active layer. In one embodiment the CVD reactor may be configured to provide a 30 nm aluminum gallium arsenide passivation layer. In one embodiment the CVD reactor may be configured to provide a dislocation density of less than 1×10 4  per centimeter squared, a photoluminescence efficiency of 99%; and a photoluminescence lifetime of 250 nanoseconds. 
     In one embodiment the CVD reactor may be configured to provide an epitaxial lateral overgrowth layer having a 5 nm deposition +−0.5 nm; a etch selectivity greater than 1×10 6 ; zero pinholes; and an aluminum arsenide etch rate greater than 0.2 mm per hour. 
     In one embodiment the CVD reactor may be configured to provide a center to edge temperature non-uniformity of no greater than 10° C. for temperatures above 300° C.; a V-III ratio of no more than 5; and a maximum temperature of 700° C. 
     In one embodiment the CVD reactor may be configured to provide a deposition layers having a 300 nm gallium arsenide buffer layer; a 5 nm aluminum arsenide sacrificial layer; a 10 nm aluminum gallium arsenide window layer; a 700 nm gallium arsenide 1×10 17  Si active layer; a 300 nm aluminum gallium arsenide 1×10 19  C P+ layer; and a 300 nm gallium arsenide 1×10 19  C P+ layer. 
     In one embodiment the CVD reactor may be configured to provide a deposition layers having a 300 nm gallium arsenide buffer layer; a 5 nm aluminum arsenide sacrificial layer; a 10 nm gallium indium phosphide window layer; a 700 nm gallium arsenide 1×10 17  Si active layer; a 100 nm gallium arsenide C P layer; a 300 nm gallium indium phosphide P window layer; a 20 nm gallium indium phosphide 1×10 20  P+ tunnel junction layer; a 20 nm gallium indium phosphide 1×10 20  N+ tunnel junction layer; a 30 nm aluminum gallium arsenide window; a 400 nm gallium indium phosphide N active layer; a 100 nm gallium indium phosphide P active layer; a 30 nm aluminum gallium arsenide P window; and a 300 nm gallium arsenide P+ contact layer. 
     While the foregoing is directed to embodiments of the invention, other and further embodiments of the invention may be devised without departing from the basic scope thereof, and the scope thereof is determined by the claims that follow.