Abstract:
This invention adds to the art of replacement source-drain cMOS transistors. Processes may involve etching a recess in the substrate material using one equipment set, then performing deposition in another. Disclosed is a method to perform the etch and subsequent deposition in the same reactor without atmospheric exposure. In-situ etching of the source-drain recess for replacement source-drain applications provides several advantages over state of the art ex-situ etching. Transistor drive current is improved by: (1) Eliminating contamination of the silicon-epilayer interface when the as-etched surface is exposed to atmosphere and (2) Precise control over the shape of the etch recess. Deposition may be done by a variety of techniques including selective and non-selective methods. In the case of blanket deposition, a measure to avoid amorphous deposition in performance critical regions is also presented.

Description:
CROSS REFERENCE TO RELATED CASES 
       [0001]    This patent application is a divisional of U.S. patent application Ser. No. 11/643,523 filed Dec. 21, 2006 entitled, “CMOS Transistor Junction Regions Formed by a CVD Etching and Deposition Sequence”, which is a divisional of U.S. patent application Ser. No. 11/029,740 filed Jan. 4, 2005 entitled, “CMOS Transistor Junction Regions Formed by a CVD Etching and Deposition Sequence.” 
     
    
     BACKGROUND 
       [0002]    Circuit devices and the manufacture and structure of circuit devices. 
       Background 
       [0003]    Increased performance in circuit devices on a substrate (e.g., integrated circuit (IC) transistors, resistors, capacitors, etc. on a semiconductor (e.g., silicon) substrate) is typically a major factor considered during design, manufacture, and operation of those devices. For example, during design and manufacture or forming of metal oxide semiconductor (MOS) transistor devices, such as those used in a complementary metal oxide semiconductor (CMOS), it is often desired to increase movement of electrons in N-type MOS device (n-MOS) channels and to increase movement of positive charged holes in P-type MOS device (p-MOS) channels. A key parameter in assessing device performance is the current delivered at a given design voltage. This parameter is commonly referred to as transistor drive current or saturation current (I Dsat ). Drive current is affected by factors that include the transistor&#39;s channel mobility and external resistance. 
         [0004]    Channel mobility refers to the mobility of carriers (i.e. holes and electrons) in the transistor&#39;s channel region. Increased carrier mobility translates directly into increased drive current at a given design voltage and gate length. Carrier mobility can be increased by straining the channel region&#39;s silicon lattice. For p-MOS devices, carrier mobility (i.e. hole mobility) is enhanced by generating a compressive strain in the transistor&#39;s channel region. For n-MOS devices, carrier mobility (i.e. electron mobility) is enhanced by generating a tensile strain in the transistor&#39;s channel region. 
         [0005]    Drive current is also influenced by other factors that include: (1) the resistances associated with the ohmic contacts (metal to semiconductor and semiconductor to metal), (2) the resistance within the source/drain region itself, (3) the resistance of the region between the channel region and the source/drain regions (i.e. the tip region), and (4) the interface resistance due to impurity (carbon, nitrogen, oxygen) contamination at the location of the initial substrate-epi-layer interface. The sum of these resistances is commonly referred to as the external resistance. 
         [0006]    Conventional tip (also commonly called source drain extensions) region fabrication is done by dopant implantation prior to fabricating the gate spacer dielectric layers. The location of the dopants is concentrated near the top surface of the substrate. This narrow band of dopants leads to high spreading resistance, and limits the current flow from channel to salicide contact. In state of the art replacement source-drain architectures, the shape of the recess is better, but is still not fully optimized with respect to spreading resistance. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0007]      FIG. 1  is a schematic cross-sectional view of a portion of a substrate having a well, gate dielectric, and gate electrode. 
           [0008]      FIG. 2  is the schematic substrate of  FIG. 1  after forming junction regions having tip regions. 
           [0009]      FIG. 3A  shows the substrate of  FIG. 2  after forming a thickness of material in the junction regions to form junctions. 
           [0010]      FIG. 3B  shows the substrate of  FIG. 2  after forming a thickness of material in junction regions having tip implants to form junctions. 
           [0011]      FIG. 4  shows a representative CMOS structure. 
           [0012]      FIG. 5  is the schematic cross-sectional view of a portion of a substrate having a well, gate dielectric, gate electrode, and junction regions having tip regions. 
           [0013]      FIG. 6  is the schematic substrate of  FIG. 5  after forming a thickness of a crystalline material in the junction regions and a thickness of amorphous material on the gate electrode. 
           [0014]      FIG. 7  shows the substrate of  FIG. 6  after removing a thickness of the crystalline material and a thickness of the amorphous material. 
           [0015]      FIG. 8  shows the substrate of  FIG. 7  after forming a subsequent thickness of a crystalline material in the junction regions and a subsequent thickness of the amorphous material on the gate electrode. 
           [0016]      FIG. 9  shows the substrate of  FIG. 8  after removing a thickness of the crystalline material and the amorphous material. 
           [0017]      FIG. 10  shows the substrate of  FIG. 9  after forming a thickness of crystalline material in the junction regions to form junctions, and after forming a thickness of amorphous material on the gate electrode. 
           [0018]      FIG. 11  shows the substrate of  FIG. 10  after removing the amorphous materials. 
           [0019]      FIG. 12  shows a representative CMOS structure. 
       
    
    
     DETAILED DESCRIPTION 
       [0020]    Locally straining transistor channel regions may be accomplished by selective epitaxial deposition of source and drain regions with materials that impart a strain in a MOS transistor&#39;s channel region. Such process flows may involve etching the substrate material from the source-drain regions of the transistor in one process operation using an etch reactor. A subsequent operation may involve replacing the removed material with Si alloy material in a deposition reactor. The etch reactor and deposition reactor may be physically different and separate. Thus the substrate must be removed from the etch reactor and exposed to atmospheric pressure environments before initiating the Si alloy deposition process. The Si alloy may be pure Si or Si 1-x Ge x  or Si 1-x C x  and can be undoped or doped with p-type or n-type dopants. The deposition process may be selective or non-selective. According to embodiments provided herein, the etch reactor and deposition reactor may be physically the same. 
         [0021]    For example,  FIG. 1  is a schematic cross-sectional view of a portion of a substrate having a well, gate dielectric, gate electrode, and tip material.  FIG. 1  shows apparatus  100  including substrate  120  having gate dielectric  144  formed on top surface  125  of substrate  120  over well  124 . Gate electrode  190  is formed on gate dielectric  144  and has spacers  112  and  114  formed on its side surfaces. Etch mask  142  is formed on gate electrode  190 . Electrically insulating material  130  is also shown to electrically isolate well  124  from surrounding regions  128 . Surface  170  and surface  180  are shown adjacent to gate electrode  190 . Apparatus  100 , and components thereof described above may be further processed, such as in a semiconductor transistor fabrication process that involves one or more processing chambers, to become or be parts of a p-MOS or n-MOS transistor (e.g., by being parts of a CMOS device). 
         [0022]    For example, substrate  120  may include, be formed from, deposited with, or grown from silicon, polycrystalline silicon, single crystal silicon, or various other suitable technologies for forming a silicon base or substrate, such as a silicon wafer. For example, according to embodiments, substrate  120  may be formed by growing a single crystal silicon substrate base material having a thickness of between 100 Angstroms and 1000 Angstroms of pure silicon. Alternately, substrate  120  may be formed by sufficient chemical vapor deposition (CVD) of various appropriate silicon or silicon alloy materials to form a layer of material having a thickness between one and three micrometers in thickness, such as by CVD to form a thickness of two micrometers in thickness. It is also considered that substrate  120  may be a relaxed, non-relaxed, graded, and/or non-graded silicon alloy material. 
         [0023]    As shown in  FIG. 1 , substrate  120  includes well  124 , such as an N-type well having an electrically negative charge on a P-type material having an electrically positive charge formed by doping substrate  120  during formation or after formation of substrate  120 . Specifically, to form well  124 , top surface  125  may be doped with phosphorous, arsenic, and/or antimony to form an N-type well of a p-MOS transistor (e.g., a p-MOS device of a CMOS device). Doping as described herein may be performed, for example, by angled doping, such as to implant ions or atoms of the above-noted dopants into a material, such as substrate  120  or a material formed in or on substrate  120 . For example, doping may include ion implantation performed by an ion “gun”, or an ion “implanter” to bombard surfaces of a substrate with accelerated high velocity ions to implant ions to form doped material. The accelerated ions may penetrate through the surface of the material and scatter into the material below to form a depth of doped material. For example, top surface  125  may be selectively doped, such as by placing a mask over the non-selected area or areas to block the introduction of the dopant from entering the non-selected are or areas, while allowing the dopant to dope well  124 . 
         [0024]    Alternatively, to form well  124 , top surface  125  may be doped with boron and/or aluminum to form a P-type well of a n-MOS transistor (e.g., a n-MOS device of a CMOS device). 
         [0025]    Thus, well  124  may be a material suitable for forming a “channel” of a transistor device. For example, a transistor device channel maybe defined as a portion of the material of well  124  under top surface  125  and between surfaces  170  and  180 , or junctions formed adjacent to, consuming portions of, and/or including surfaces  170  and  180 . 
         [0026]      FIG. 1  shows electrically insulating material  130  between well  124  and surrounding regions  128 . Material  130  may be various appropriate electrically insulating materials and structures sufficient for electrically isolating well  124  from surrounding regions  128 . For example, surrounding regions  128  may be well regions of adjacent or related transistor devices. Specifically, material  130  may be shallow trench isolation (STI) formed between an N-type well of a p-MOS device (e.g., where well  124  has an N-type well) and other regions of substrate  120  to electrically isolate the N-type well from the other regions. Similarly, material  130  may be STI formed between a P-type well of a n-MOS device (e.g., where well  124  is a P-type well) and other regions of substrate  120 . Thus, material  130  may isolate well  124  from other regions of substrate  120  to provide for functionality of a transistor formed on top surface  125  (e.g., to isolate well  124  from an adjacent well of an associated device paired with well  124  to form a CMOS device). In one example, where well  124  is an N-type well, one of regions  128  may be a related P-type well of an n-MOS device paired with a p-MOS device formed on top surface  125  to form a CMOS device. Alternatively, where well  124  is a P-type well, one of regions  128  may be a related N-type well of a p-MOS device paired with a n-MOS device formed on top surface  125  to form a CMOS device. Material  130  may be formed by doping through a layer of material located above material  130 , and/or may be formed before or after forming well  124 . 
         [0027]    As shown in  FIG. 1 , gate dielectric  144  has width W 2 . Gate electrode  190  is shown formed on gate dielectric  144  with width W 1 . The thickness of gate dielectric  144  may be generally consistent throughout and conform to the topography of top surface  125  along width W 2 . Moreover, gate dielectric  144  may be formed of a material having a relatively high dielectric constant (e.g., a dielectric constant greater than or equal to that of silicon dioxide (SiO 2 ), or of a material having a relatively low dielectric constant. A thickness of gate dielectric  144  may be between one and five nanometers in thickness. Gate dielectric  144  may be formed by deposition, such as by CVD, atomic layer deposition (ALD), blanket deposition, selective deposition, epitaxial deposition, ultra high vacuum (UHV) CVD, rapid thermal (RT) CVD, reduced pressure (RP) CVD, molecular beam epitaxy (MBE), and/or other appropriate growing, depositing, or forming processes. Gate dielectric  144  may have an appropriate P-type work function for apparatus  100 , such as where apparatus  100  is a p-MOS device. Alternatively, gate dielectric  144  may have an appropriate N-type work function for apparatus  100 , such as where apparatus  100  is an n-MOS device. Specifically, gate dielectric  144  may be formed of dielectrics such as silicon dioxide (SiO 2 ), hafnium oxide (HfO), hafnium silicate (HfSiO 4 ), zirconium oxide (ZrO), carbon doped oxide (CDO), cubic boron nitride (CBN), phosphosilicate glass (PSG), silicon nitride (Si 3 N 4 ), fluorinated silicate glass (FSG), silicon carbide (SiC), etc. 
         [0028]    Gate electrode  190  may be formed, such as by processes described above with respect to forming gate dielectric  144 . Moreover, gate electrode  190  may be formed of various semiconductor or conductor materials, such as silicon, polysilicon, crystal silicon, and/or various other appropriate gate electrode materials. Also, gate electrode  190  may be doped during or after formation. For example, gate electrode  190  may be doped with boron and/or aluminum to form a p-type gate electrode having an electrically positive charge (e.g., for a p-MOS device, which may be part of a CMOS device). Conversely, it is also contemplated, that gate electrode  190  may be doped with phosphorous, arsenic, and/or antimony to form a n-type gate electrode having an electrically negative charge (e.g., for a n-MOSn-MOS device, which may be part of a CMOS device). 
         [0029]    Gate electrode  190  may have a thickness appropriate for a p-MOS or n-MOS device, such as when apparatus  100  is a p-MOS or n-MOS device. For example, gate electrode  190  may have a thickness to cause a transistor formed on substrate  120  to have a threshold “ON” voltage between 0.1 and 0.5 volts. In some cases, gate electrode  190  may have a thickness of, for example, between 150 and 2000 Angstroms (e.g., between 15 and 200 nanometers (nm)). Gate electrode  190  may have a work function for responding to a gate electrode of a p-MOS device (e.g., where apparatus  100  is a p-MOS device). Alternatively, gate electrode  190  may have a work function for responding to a gate electrode of a n-MOS device (e.g., where apparatus  100  is a n-MOS device). 
         [0030]      FIG. 1  shows spacer  112  and spacer  114  formed on surfaces of gate electrode  190  and gate dielectric  144 . Specifically, spacer  112  and spacer  114  may be formed on sidewall surfaces of gate electrode  190  and on a top surface of gate dielectric  144  (e.g., a surface opposite from substrate  120 ). Spacers  112  and  114  may be a dielectric material such as silicon nitride (Si 3 N 4 ), silicon dioxide (SiO 2 ), and/or various other appropriate semiconductor device spacer materials. 
         [0031]      FIG. 1  also shows etch mask  142  formed on gate electrode  190 . Etch mask  142  may be a “hard” mask formed of silicon nitride (Si 3 N 4 ), where other material mentioned above for forming gate dielectric  144 . For example, etch mask  142  may be used when forming gate electrode  190 , gate dielectric  144  and/or spacers  112  and  114 . Specifically, portions corresponding to the shape of mask  142  or area around mask  142  may be removed or etched away from above, using mask  142  as an etch stop. 
         [0032]    For example, spacers  112  and  114  may be formed by first depositing dielectric material, similar to dielectric materials described above for gate dielectric  144 , conformally along surfaces of substrate  120 , sidewall surfaces of gate electrode  190 , and a top surface etch mask  142 . Then the formed or deposited dielectric material may be patterned and etched to create spacers  112  and  114 . 
         [0033]    According to embodiments, portions of well  124  and substrate  120 , such as at surfaces  170  and surface  180 , may be removed to form a junction regions in substrate  120  adjacent to gate electrode  190 . For example, junctions adjacent to gate electrode  190  may be formed by removing portions of substrate  120  at surfaces  170  and  180  to form junction regions or recesses in substrate  120 , and then forming or depositing a junction material into the junction regions. Such removal may include “source-drain recess” etching, so that the junction regions extend under gate dielectric  144 . 
         [0034]    For example,  FIG. 2  is the schematic substrate of  FIG. 1  after forming junction regions having tip regions.  FIG. 2  shows junction region  270 , such as a recess formed in surface  170  of substrate  120  adjacent to gate electrode  190  and source-drain recess below a bottom surface of gate dielectric  144 . Similarly,  FIG. 2  shows junction region  280 , such a recess formed in surface  180  of substrate  120  adjacent to gate electrode  190 , and source-drain recess below a bottom surface of gate dielectric  144 . 
         [0035]    Junction region  270  defines substrate surface  222  (e.g., a base surface of junction region  270 ), facet  220 , and tip region  276 . Tip region  276  is between facet  220  and the bottom surface of gate dielectric  144 . For instance, it can be said that tip region  276  defines facet  220  having angle A 1  between facet  220  and the bottom surface of gate dielectric  144  Similarly, junction region  280  defines substrate surface  232 , facet  230 , and tip region  286 . Tip region  286  is between facet  230  and the gate dielectric  144 . Thus, tip region  286  defines facet  230  having angle A 2  between facet  230  and bottom surface of gate dielectric  144 . 
         [0036]    According to embodiments, preferred angles A 1  and/or A 2  may be angles of between 52° (degrees) and 57°. For example, angles A 1  and A 2  may both be approximately 52°, 53°, 54°, 54.7°, 54.74°, 54.739137°, 54.8°, 55°, 56°. This range of angles corresponds roughly to alignment with the {111} family of planes as described using conventional Miller index nomenclature. Alternative embodiments allow the A 1  and A 2  angles to be in the range 0° to 90°, and excluding the preferred range listed above. 
         [0037]    According to embodiments, tip regions  276  and  286  may extend under spacer  112 , spacer  114 , and/or gate electrode  190 . For example, tip regions  276  and  286  may extend along top surface  125  under the bottom surface of gate dielectric  144  from a width equal to width W 2  to a width of less than width W 2 , such as a width of greater than zero. Thus, facets  220  and  230  may contact the bottom surface of gate dielectric  144  adjacent to top surface  125  of substrate  120  to form a channel under top surface  125  between facets  220  and  230  (e.g., a channel of a transistor formed in apparatus  200 ), where facets  220  and  230  may each extend under gate dielectric  144  by a distance of between zero and one-half of width W 2 . Thus, portions of substrate  120  may be removed to form facets  220  and  230  contacting and extending under the bottom surface of gate dielectric  144  to contact the bottom surface of gate dielectric  144  under spacer  112 , spacer  114 , and/or gate electrode  190 . 
         [0038]    It is contemplated that junction region  270  and/or  280  may have a depth below top surface  125  between 800 angstroms and 1300 angstroms. Moreover, junction region  270  and/or  280  may have a width or size appropriate for depositing material into those regions to form junction of a transistor device (e.g., a p-MOS or n-MOS device of a CMOS device). 
         [0039]    Junction region  270  and/or  280  may be referred to as “source-drain regions” or “diffusion regions.” Also, when an appropriate material is formed, deposited, or grown in junction regions  270  and  280 , the resulting material may be referred to as a “junction,” a “source,” a “drain,” or a “diffusion region.” 
         [0040]    According to embodiments, junction regions  270  and  280  may be formed by removing undesired portions of substrate  120 , such as at surfaces  170  and  180 . For instance, a patterning two operation process may be used where in the first operation, a photo-resist is used to define regions of a hardmask to be removed (e.g., a hardmask layer over apparatus  100  of  FIG. 1 ). Those regions of the hardmask are then etched away. After that etching, the photo-resist is removed, and a recess etch is performed to form junction regions  270  and  280  by removing undesired portions of substrate  120  (e.g., etching away the undesired exposed portions, not covered by the remaining hardmask). Photolithographic patterning using an etch stop, dielectric material, photo resist, or other suitable material for masking and etch processing (e.g., a negative photo-resist mask, positive photo-resist mask, silicon dioxide SiO 2 ), or silicon nitride Si 3 N 4 ) may also be used to define an area to be protected while source-drain recess etching to form junction regions  270  and  280 , as shown in  FIG. 2 . 
         [0041]    Suitable non-plasma etch chemistries for removing undesired portions of substrate  120 , such as at surfaces  170  and  180  to form junction regions  270  and  280  include chlorine (Cl 2 ), hydrochloric acid (HCl), fluorine (F 2 ), bromine (Br 2 ), HBr and/or other etch processes capable of removing portions of substrate  120 . Plasma etches including chemistries of SF 6 , NF 3  or the like are possible as alternative embodiments. Typical epitaxial deposition equipment types available today (e.g., chambers or reactors) can perform the above noted non-plasma etches with little or no modification. A change to enable plasma etching as noted above and CVD deposition in the same reactor is possible, but adds a great deal of complexity to the hardware (e.g., chambers or reactors). 
         [0042]    Suitable chambers for etching junction regions  270  and  280  include a CVD chamber, an ALD chamber, a UHVCVD chamber, an RTCVD chamber, an RPCVD chamber, an MBE chamber, a “batch” UHV CVD chamber, a cold-wall UHV CVD chamber, an atmospheric pressure (AP) CVD chamber a low-pressure (LP) CVD chamber, or a chamber reactor that combines the functionality of one or more of these chambers or reactors. 
         [0043]    Moreover, etching to form junction regions  270  and  280  may be performed at a pressure of between 1E-4 Torr and 1,000 Torr (e.g., at a pressures within a one decimal range of 1E-3, 1E-2, 0.1, 1.0, 10, 100, or 1000 Torr) in either a “cold-wall” or “hot-wall” reactor. Also, etching to form junction regions  270  and  280  may be performed at typical epitaxial silicon alloy deposition temperatures, for example from 500 to 900° C. A “cold-wall” reactor may be described as a reactor having vessel walls that, during deposition or etching, are at room temperature. A “cold-wall” reactor may have vessel walls fabricated from metal. Alternatively, a “hot-wall” reactor may have vessel wall fabricated from quartz or other ceramics that are at a temperature greater than room temperature during deposition or etching. 
         [0044]    For example, junction region  270  and/or  280  may be formed by removing or etching portions of substrate  120  with etchant gas that may contain mixtures including: chlorine (Cl 2 ), hydrochloric acid (HCl), hydrogen (H 2 ), and/or nitrogen (N 2 ). Specifically, an etchant or gas including one or more of the above-noted gases may flow into a chamber in which apparatus  100  is housed at a rate of between five standard cubic centimeters per minute (SCCM) and ten SCCM, at a temperature of between 500 degrees Celsius (° C.) and 800° C. (e.g., a temperature of 500, 525, 540, 550, 560, 575, 600, 625, 650, 675, 700, 750, or 800° C.) for between 30 and 90 minutes (e.g., a period of 30, 35, 40, 45, 50, 55, 60, 65, 75, 85, or 90 minutes) to etch portions of substrate  120  at surfaces  170  and  180 . According to embodiments, junction region  270  and/or  280  may be formed at a pressure of between 3E-3 Torr and 7E-3 Torr (e.g., 3E-3, 3.5E-3, 4E-3, 4.5E-3, 5E-3, 5.5E-3, 6E-3, 6.5E-3, or 7E-3). In some cases, chlorine gas is used to etch junction regions  270  and  280  in a chamber as described above, at a temperature of 650° C. and at a pressure of between 3E-3 Torr and 7E-3 Torr, in a 300 millimeter (mm) UHV CVD cold-wall single wafer reactor. 
         [0045]    For example,  FIG. 3A  shows the substrate of  FIG. 2  after forming thickness of a material in the junction regions to form junctions.  FIG. 3A  shows apparatus  300  having material  370  formed in junction region  270  and material  380  formed injunction region  280 . Material  370  and/or material  380  may be described as a junction, source, drain, or diffusion region. In addition, material  370  may be formed to have junction top surface  372  that is superior to top surface  125  of substrate  120 . Specifically, material  370  may be a thickness of silicon germanium material having a lattice spacing greater than a lattice spacing of the material of substrate  120 . Likewise, material  380  may be formed to have junction top surface  382  that is also superior to top surface  125 . For example, material  370  may be thickness T 4  of an epitaxial thickness of crystalline silicon-germanium alloy, geranium, or silicon material (e.g., SiGe, such as Si X Ge 1-X ), where the size and/or thickness T 4  is sufficient to cause a compressive strain in substrate  120 . The material may be pure or doped with p-type dopants such as B and A 1 . Alternatively, material  370  may be thickness of T 4  of an epitaxial thickness of crystalline silicon-carbon alloy material (e.g., Si x C 1-x ), where the size and/or thickness of T 4  is sufficient to cause a tensile strain in substrate  120 . The material may be pure or doped with n-type dopants such as P, As and Sb. For example, material  370  may be a thickness of silicon-carbon alloy (Si x C 1-x ) having a lattice spacing smaller than a lattice spacing of substrate  120 . Similarly, material  380  may be a thickness T 5  of an epitaxial thickness of crystalline silicon-germanium alloy (Si x Ge 1-x ) having sufficient size and/or thickness T 5  to cause a strain in substrate  120 . 
         [0046]    For example, as shown in  FIG. 3A , material  370  may cause compressive strain  374  towards a portion of substrate  120  under top surface  125 , and material  380  may cause compressive strain  384  towards the same portion of substrate  120 . Thus, strain  374  may cause compressive strain  392  and strain  384  may cause compressive strain  394  in a channel of substrate  120  between material  370  and material  380  (e.g., a compressive strain between p-type junction material formed injunction regions  270  and  280  and in the channel of apparatus  300 , where apparatus  300  is a p-MOS device). It can be appreciated that compressive strains  392  and  394  may be strains between facets  220  and  230  sufficient to increase carrier mobility (e.g., mobility of holes in the channel of well  124 ) between material  370  and material  380 . In other words, a channel in substrate  120  may be under a compressive strain caused by a lattice spacing of material  370  and/or material  380  (e.g., where material  370  and material  380  are silicon-germanium alloy material) being larger than a lattice spacing of the material of substrate  120 . 
         [0047]    In another example, material  370  and material  380  may cause a tensile strain in a channel of apparatus  300  (e.g., if the direction of strains  374 ,  384 ,  392 , and  394  were reversed). In this case a tensile strain in the channel of apparatus  300 , where apparatus  300  is a n-MOS device may be a strain between facets  220  and  230  sufficient to increase carrier mobility (e.g., mobility of electrons in the channel of well  124 ) between material  370  and material  380 . Correspondingly, a channel in substrate  120  may be under a tensile strain caused by a lattice spacing of material  370  and/or material  380  (e.g., where those materials are silicon-carbon alloy) being larger than a lattice spacing of new material of substrate  120 . 
         [0048]    Material  370  and material  380  may be deposited by chemical vapor deposition or other processes described above for forming gate dielectric  144 . For example, material  370  and material  380  may be formed in a chamber as described above for forming junction regions  270  and  280 , and for forming gate dielectric  144 . Suitable chambers for forming, growing, or depositing materials  370  and  380  include equipment capable of selective deposition of silicon-based elemental or alloyed films. For instance, some suitable chambers for forming material  370  and material  380  include a CVD chamber, an ALD chamber, a UHVCVD chamber, an RTCVD chamber, an RPCVD chamber, an MBE chamber, a “batch” UHV CVD chamber, a cold-wall UHV CVD chamber, an atmospheric pressure (AP) CVD chamber a low-pressure (LP) CVD chamber, or a chamber reactor that combines the functionality of one or more of these chambers or reactors. 
         [0049]    Suitable deposition techniques include thermal decomposition of hydride or chlorinated hydride precursor gases on silicon wafers. Deposition pressure may be between 1E-4 Torr and 1000 Torr (e.g., at a pressures within a one decimal range of 1E-3, 1E-2, 0.1, 1.0, 10, 100, or 1000 Torr). Deposition may occur in a cold-wall or hot-wall reactor. Specifically, material  370  and  380  may be formed by selective deposition of silane, disilane, dichlorosilane, and/or methylsilane gas to chemically bond a thickness of silicon alloy or silicon elemental material to surfaces of junction region  270  and  280  to form junctions therein. In an alternative embodiment, this can be performed by non-selective deposition using trisilane as the silicon precursor, and the same alloy and dopant precursor gases mentioned below. 
         [0050]    In some process, deposition is performed in a 300 mm epitaxial UHV CVD cold-wall single wafer reactor. Appropriate temperatures for forming material  370  and  380  include room temperature, or a temperature of between 500 and 800° C., and at a pressure of between 300 E-3 Torr and 7 E-3 Torr (e.g., 3E-3, 3.5E-3, 4E-3, 4.5E-3, 5E-3, 5.5E-3, 6E-3, 6.5E-3, or 7E-3). In some examples, material  370  and  380  is formed by introducing disilane at between seven standard cubic centimeters per minute (SCCM) and 20 SCCM, and introducing methylsilane at between 10 SCCM and 300 SCCM. For example, thickness T 4  and/or T 5  may be a thickness of between 1000 angstroms and 1500 angstroms, such as a thickness of 1050, 1100, 1150, or 1200 angstroms. 
         [0051]    Material  370  and  380  may be doped during formation and/or doped after formation. In some embodiments, material  370  and/or  380  may be alloyed or doped during deposition when the silicon precursor flow is accompanied with germane, methylsilane, acetylene, diborane, boron chloride, phosphine, arsine, and/or stibnite. For instance, during or after formation, material  370  and  380  may be doped, such as by boron and/or aluminum to form P-type junction material having an electronically positive charge. In one embodiment, material  370  and material  380  may be formed as boron and/or aluminum doped epitaxial crystalline silicon-germanium alloy material in junction regions  270  and  280 , and then subsequently doped with additional boron and/or aluminum. 
         [0052]    Alternatively, during and/or after formation, material  370  and  380  may be doped, such as by phosphorous, arsenic, and/or antimony to form an N-type junction material having an electrically negative charge. In one embodiment, material  370  and  380  may be silicon carbon alloy epitaxial crystalline material formed in junction regions  270  and  280 , and subsequently doped with additional phosphorous, arsenic, and/or antimony. 
         [0053]    Thus, material  370  and  380  may be (Si x (Ge) 1-x :(B,Al) for p-MOS and Si x C 1-x :(P,As,Sb) for n-MOS. Subsequent to forming material  370  and  380 , apparatus  300  may be thermally treated, such as by annealing. 
         [0054]    Moreover, according to embodiments, forming of junction regions  270  and  280 , and forming, depositing, or growing of material  370  and material  380  may occur in the in the same chamber, in the same reactor, at the same pressure, at the same temperature, in the same setting, and/or in a chamber or reactor without breaking a seal or vacuum of the chamber or reactor. The process consists of an initial set of etch gas flows, followed by a set of deposition gas flows. Thus, forming material  370  and  380  may be performed in-situ with forming junction regions  270  and  280 . It can be appreciated that forming of junction regions  270  and  280  in the same chamber used to deposit material  370  and  380 , may reduce undesired impurities including carbon, oxygen and nitrogen in surfaces of junction regions  270  and  280 , and material  370  and  380 . A suitable chamber for forming of junction regions  270  and  280 , and for forming material  370  and  380  includes chambers described above for forming junction regions  270  and  280 . 
         [0055]    For instance, some suitable chambers for forming of junction regions  270  and  280 , and for forming material  370  and  380  in the same chamber include a CVD chamber, an ALD chamber, a UHVCVD chamber, an RTCVD chamber, an RPCVD chamber, an MBE chamber, a “batch” UHV CVD chamber, a cold-wall UHV CVD chamber, an atmospheric pressure (AP) CVD chamber a low-pressure (LP) CVD chamber, or a chamber reactor that combines the functionality of one or more of these chambers or reactors. Deposition mode may be selective or non-selective. Moreover, forming of junction regions  270  and  280  and depositing material  370  and  380  can be performed in the same chamber in the same vacuum (e.g., without opening the chamber, opening a seal of the chamber or exposing the inside of the chamber to air from outside of the chamber). For example, junction regions  270  and  280 , and material  370  and  380  can be formed in a chamber having a pressure of between 1E-4 Torr and 1000 Torr (e.g., at a pressures within a one decimal range of 1E-3, 1E-2, 0.1, 1.0, 10, 100, or 1000 Torr) without opening the chamber, opening a seal of the chamber or exposing the inside of the chamber to air from outside of the chamber. 
         [0056]    In one example, a process to perform in-situ recessed source drain etch (e.g., performing junction regions  270  and  280 ) followed immediately by deposition of source drain material (e.g., deposition of material  370  and  380 ) is performed in a UHV CVD chamber (e.g., a 300 mm epitaxial UHV CVD cold-walled single-wafer reactor. This process uses a set of etch gases and a set of deposition gases to form junction regions having facets  220  and  230 , and then to selectively deposit silicon or silicon alloy material to form junctions on those facets. Moreover, hydrogen (H 2 ) and/or nitrogen (N 2 ) may be used as carrier gases during the etch and/or deposition processes. It is observed that the deposition of materials  370  and  380  may follow the etching of regions  270  and  280  immediately, such as by occurring as the next operation in the processing of apparatus  200 , occurring before a seal or vacuum of the chamber is opened, occurring within 30 minutes of forming a recess in regions  270  and  280 , and/or occurring after a “pump out” of the chamber to remove the etchant or gas used to form regions  270  and  280 . 
         [0057]    In one example, an etch process using a flow rate of pure chlorine gas of between five and ten SCCM for a period of between ten and 300 minutes (e.g., a period of 30, 40, 50, 60, 70, 80, 90, 100 or 120 minutes) is used to form regions  270  and  280 . Following pump-out of the pure chlorine gas, a deposition process occurs to form materials  370  and  380  in regions  270  and  280 , in the same chamber, without exposing the inside of the chamber to the outside air. 
         [0058]    The deposition process may include a flow rate of between seven and 20 SCCM of disilane and between ten and 30 SCCM of methylsilane for a period of between ten and 200 seconds (e.g., a period of 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80 or 90 seconds), the disilane and methylsilane are then pumped out during a five-second period, this pump-out period is followed by introduction of a pure chlorine gas at a flow rate of between five and 15 SCCM for a period of between ten and 200 seconds (e.g., a period of 10, 15, 20, 25, 30, 35, 40, 45, 50, 60, 70, 80 or 90 seconds). The chlorine gas is then pumped out for a period of 5 seconds. The introduction of disilane, methylsilane, and subsequent chlorine etch are repeated between 50 and 100 time (e.g., by repeating 70 times, 75 times, 80 times, 85 times, or another number of times between 50 and 100 times) to form material  370  and  380 . 
         [0059]    In one example, recessed source drain etch is performed in-situ with deposition of the source drain material in a 300 millimeter (mm) wafer UHV CVD cold-wall single wafer reactor. First, junction regions  270  and  280  are formed by removing or etching portions of substrate  120  with pure chlorine flowing into the chamber at a rate of between five standard cubic centimeters per minute (SCCM) and ten SCCM for one hour while the reactor is kept at a temperature of 650 degrees Celsius. Junction regions  270  and  280  are formed to a depth of 1000 angstroms. 
         [0060]    Next, material  370  and  380  are formed in regions  270  and  280  “immediately” after etching (e.g., no other processing is performed between pumping out the chlorine etchant and depositing material  370  and  380 ) by a standard MOS integration while the reactor is kept at a temperature of 650 degrees Celsius. For instance, material  370  and  380  are formed or deposited by introducing pure disilane at a flow rate of between seven and 20 SCCM and ten percent methylsilane in H 2  at a flow rate of between 10 and 30 SCCM for a period of 30 seconds, and the pumping out for a period of five seconds. The pump-out period is followed by introduction of pure chlorine gas at a flow rate of between five and 15 SCCM for a period 30 seconds, and the pumping out for a period of five seconds. 
         [0061]    The sequence of introducing disilane and methylsilane, pumping out, introducing chlorine and pumping out is repeated 75 times to form material  370  and  380  of Si—C alloy with one atomic percent of C and a thickness of 1100 angstroms. Moreover, it can be appreciated that the seal or vacuum of the reactor can be kept intact during the 75 iterations. Similarly, the pressure of the chamber and a temperature of 650 degrees Celsius may be maintained during the 75 iterations. 
         [0062]    Thus, material  370  and  380  may be formed as an epitaxial layer of Si—C alloy with an atomic percent of C of between 0.1 and two percent (e.g., one percent) of carbon and a thickness of 1100 angstroms. Alternatively, material  370  and  380  may be formed of a SiGe alloy with an atomic percentage of Ge of between 10 and 40 percent (e.g., 20 percent) and a thickness of 100 angstroms. 
         [0063]    It can be appreciated that by forming junction regions  270  and  280 , and material  370  and  380  by processes described above and/or in the same chamber without breaking vacuum or a seal of the chamber forms very high-quality epitaxial film junction region material  370  and  380  in junction regions  270  and  280  without interfacial contaminants, and strained channels for increased electron or hole mobility, as well as increased drive current in at least the following four ways:
       1. Facets  220  and  230  may be well defined high quality interfaces for the epitaxial material at the junction location due to high purity. For example, the formation of regions  270  and  280  (including facets  220  and  230 ) and the formation of material  370  and  380  in a single chamber as described above may decrease the interface resistance due to impurity (e.g., by decreasing the amount of carbon, nitrogen, oxygen in the interface) contamination at the location of the initial substrate-epi-layer interface (e.g., between facets  220  and  230  and material  370  and  380 ), leading to better interface control, lower R external  and higher drive current. Similarly, such formation may decrease in interface impurity contamination in material  370  and  380  allowing for higher dopant concentrations in material  370  and  380  (e.g., such as boron, aluminum, phosphorus, arsenic and/or antimony), and providing lower resistance within the source/drain region itself, thus causing better interface control, lower R external  and higher drive current.   2. The shape of the source-drain recess with facets  220  and  230  angled near 54° provides optimum current spreading. For example, the angle, alignment, and planar characteristics of facets  220  and  230  formed as described above may provide optimal tip shapes and orientations that allow current to spread through the facets and tips (e.g., current flowing between material  370  and  380  and the channel region) more evenly and easily (e.g., in greater overall magnitude or amount) causing lower resistance of the region between the channel region and material  370  and  380  (i.e. the tip region), leading to lower R external  and higher drive current.   3. Facets  220  and  230  angled near 54° also provide maximum resistance to dopant over-run that can cause shorts below the channel, as well as short channel effects. The recess and tip regions  376  and  486  can be placed in closer proximity to the channel without fear of short channel effects or shorting.   4. Strain relaxation by formation of misfit dislocations is enhanced when interface contamination is present. This invention allows use of higher strain in deposited films without relaxation. For instance, the formation of regions  270  and  280  (including facets  220  and  230 ) and the formation of material  370  and  380  in a single chamber as described above may allow for higher germanium or carbon concentrations in material  370  and  380 , leading to higher amounts of strain in the channel causing higher carrier mobility and drive current during transistor use.       
 
         [0068]    Moreover, when forming junction regions  270  and  280 , and material  370  and  380  by processes described above, the native oxide build-up at the junction/substrate interface is reduced (e.g., the interface between material  370  and  380  and well  124  of substrate  120 ); the carbon, oxygen, and/or nitrogen contamination at those interfaces is reduced; the need for wet cleans (e.g., and processing queue time restrictions required for the cleans) is not necessary; the number of tool types required during processing is reduced; loading in nested regions is reduced; planar, smooth, and appropriately oriented tip profiles (e.g., for tips  376  and  386 ) with (1,1,1) facets are produced; electron and/or hole mobility in the channel is improved due to strain from (Si x Ge 1-x ):B,Al for p-MOS and (Si x C 1-x ):P, As, Sb for n-MOS within junction regions); reduces R External  is reduced due to the high concentration of dopants allowable (e.g., phosphorous or boron doped in the junctions during and/or after epitaxial deposition to form (Si x Ge 1-x ):B,Al for p-MOS and (Si x C 1-x ):P, As, Sb for n-MOS. 
         [0069]    In addition, the concepts described above can be applied to form a transistor having junction regions (e.g., source drain regions) that extend under the spacers but not under the gate electrode. In such a case, tip implants (e.g., doped substrate material) may be formed adjacent to the junction regions under the gate electrode. For instance,  FIG. 3B  shows the substrate of  FIG. 2  after forming a thickness of material in junction regions having tip implants to form junctions.  FIG. 3B  shows junction regions  270  and  280  (e.g., source drain regions) extending under spacers  112  and  114  but not under the gate electrode  190 . Also shown, tip implants  354  and  364  (e.g., doped substrate material) may be formed adjacent to the junction regions under the gate electrode. Tip implants  354  and  364  may be formed by standard process in the industry, such as by doping substrate  120  during formation or after formation of substrate  120 . Specifically, to form well  124 , top surface  125  may be doped with boron and/or aluminum to form p-type tip implants of a p-MOS transistor. After doping the surface of substrate  120  to form the p-type material of the tip implants, portions of the p-type material may be removed or etched to form junction regions  270  and  280  as described above with respect to  FIG. 2 . Thus, as shown in  FIG. 3B  facets  320  and  330  may be described as having tips (e.g., tip implants) fabricated from deposited material formed under the bottom surface of the gate dielectric. 
         [0070]    Similar to  FIG. 3A ,  FIG. 3B , shows that material  370  may cause compressive strain  374  towards a portion of substrate  120  under top surface  125 , and material  380  may cause compressive strain  384  towards the same portion of substrate  120 . Thus, strain  374  may cause compressive strain  392  and strain  384  may cause compressive strain  394  in a channel of substrate  120  between tip implants  354  and  364 . It can be appreciated that compressive strains  392  and  394  may be strains between facets  220  and  230  and tip implants  354  and  364  sufficient to increase carrier mobility (e.g., mobility of holes in the channel of well  124 ) between material  370  and material  380  and tip implants  354  and  364 . 
         [0071]    In another example, material  370  and material  380  may cause a tensile strain in a channel of apparatus  300  (e.g., if the direction of strains  374 ,  384 ,  392 , and  394  were reversed). In this case a tensile strain in the channel of apparatus  300 , where apparatus  300  is a n-MOS device may be a strain between facets  220  and  230  and tip implants  354  and  364  sufficient to increase carrier mobility (e.g., mobility of electrons in the channel of well  124 ) between material  370  and material  380 . 
         [0072]    For example,  FIG. 4  shows a representative CMOS structure.  FIG. 4  shows CMOS device  400  having p-MOS device, such as a p-MOS embodiment of apparatus  300  as described above with respect to  FIGS. 3A and 3B , connected to n-MOS transistor device  478  in typical fashion. Substrate  120  includes P-type well  422  related to N-type well  124  for forming CMOS device  400 , such that P-type well  422  is part of n-MOS transistor device  478  formed on a second area of substrate  120  and defining a different second interface surface  425  of substrate  120  adjacent to N-type well  124 . Specifically, for instance, n-MOS device  478  may be formed adjacent to p-MOS apparatus  300  by having n-MOS device  478  electrically isolated from p-MOS apparatus  300  by electrically insulating material  130  as described herein. Moreover, n-MOS device  478  may include a channel below gate dielectric  444  which is below gate electrode  490 , and between N-type junctions  470  and  480 . n-MOS device  478  is also shown with spacers  412  and  414 . n-MOS device  478  may be an n-MOS embodiment of apparatus  300  as described above with respect to  FIGS. 3A  and B. Thus, CMOS device  400  has ground GND, input voltage V in  output voltage V out , and bias voltage V DD . 
         [0073]    According to embodiments, the technology and processes described above with respect to  FIGS. 1-4 , may or may not be combined with a process for blanket or non-selective deposition of an epitaxial thickness of crystalline material into junction regions to form junctions and a conformal thickness of an amorphous material over a gate electrode, such as during formation of a transistor device. For example, the technology and processes described above with respect to  FIGS. 1-4 , may or may not be combined with the processes and devices described below with respect to  FIGS. 5-12 . 
         [0074]      FIG. 5  is the schematic cross-sectional view of a portion of a substrate having a well, gate dielectric, gate electrode, and junction regions having tip regions.  FIG. 5  shows apparatus  500  including substrate  505  having gate dielectric  544  formed on top surface  525  of substrate  505  over well  524 . Gate electrode  590  is formed on gate dielectric  544  and has spacers  512  and  514  formed on its side surfaces. Etch mask  542  is formed on gate electrode  590 . Electrically insulating material  510  is also shown to electrically isolate well  524  from surrounding regions  528 . Junction regions  570  and  580  are shown adjacent to gate electrode  590 . Apparatus  500 , and components thereof described above may be further processed, such as in a semiconductor transistor fabrication process that involves one or more processing chambers, to become or be parts of a p-MOS or n-MOS transistor (e.g., by being parts of a CMOS device). 
         [0075]    Features, of  FIG. 5  may or may not “correspond” to features of  FIG. 1  as described above (e.g., “correspond,” such as by having corresponding or similar features, materials, doping, widths, lengths, depths, thicknesses, and functionality; being formed in corresponding or similar chambers or reactors, and/or being formed by corresponding or similar processes). For example, in  FIG. 5 , substrate  505  may correspond to substrate  120 , etch mask  542  may correspond to etch mask  142 , spacers  512  and  514  may correspond to spacers  112  and  114 , width W 51  may correspond to width W 1 , width W 52  may correspond to width W 2 , and top surface  525  may correspond to top surface  125  of  FIG. 1 , as described above. 
         [0076]    Moreover, in  FIG. 5 , well  524  may correspond to a P-type well of a n-MOS transistor as described above with respect to well  124  of  FIG. 1 . Specifically, to form well  524 , top surface  525  may be doped with boron and/or aluminum to form a P-type well of a n-MOS transistor (e.g., a n-MOS device of a CMOS device). Thus, well  524  may be a material suitable for forming a “channel” of an n-MOS transistor device. For example, a transistor device channel maybe defined as a portion of the material of well  524  under top surface  525  and between junction regions  570  and  580 , or junctions formed therein. 
         [0077]    Also, in  FIG. 5 , material  510  may correspond to material  130 , and surrounding regions  528  may correspond to surrounding regions  128 , of  FIG. 1 . Specifically, material  510  may be shallow trench isolation (STI) formed between a P-type well of a n-MOS device (e.g., where well  524  has a P-type well) and other regions of substrate  505  to electrically isolate the P-type well from the other regions (e.g., where one of other regions  528  is an N-type well of a p-MOS device in substrate  505 ). 
         [0078]    Next, gate dielectric  544  of  FIG. 5  may correspond to gate dielectric  144  of  FIG. 1  as described above. For instance, gate dielectric  144  may have an appropriate N-type work function for apparatus  500 , such as where apparatus  500  is an n-MOS device. 
         [0079]    Furthermore, in  FIG. 5 , gate electrode  590  may correspond to gate electrode  190  of  FIG. 1  as described above. Thus, gate electrode  590  may be doped with phosphorous, arsenic, and/or antimony to form an N-type electrode material having an electrically negative charge (e.g., for a n-MOS device, which may be part of a CMOS device). Gate electrode  590  may have a thickness appropriate for a p-MOS or n-MOS device, such as when apparatus  500  is an n-MOS device. Gate electrode  590  may have a work function for responding to a gate electrode of an n-MOS device (e.g., where apparatus  500  is an n-MOS device). 
         [0080]      FIG. 5  shows junction region  570 , such as a recess formed a surface of substrate  505  adjacent to gate electrode  590  and source-drain recess below a bottom surface of gate dielectric  544 . Similarly,  FIG. 5  shows junction region  580 , such a recess formed in a surface of substrate  505  adjacent to gate electrode  590 , and source-drain recess below a bottom surface of gate dielectric  544 . 
         [0081]    Portions of well  524  and substrate  505  of  FIG. 5  may be removed to form recesses such as junction regions  570  and  580  in substrate  505  adjacent to gate electrode  590 . For example, junctions adjacent to gate electrode  590  may be formed by forming or depositing a junction material into junction regions  570  and  580 . Such removal may include “source-drain recess” etching as described above with respect to forming junction regions  270  and  280  of  FIG. 2 , so that junction regions  570  and  680  extend under gate dielectric  544 . 
         [0082]    Junction region  570  defines substrate surface  522  (e.g., a base surface of junction region  570 ), facet  520 , and tip region  576 . Tip region  576  is between facet  520  and the bottom surface of gate dielectric  544 . Similarly, junction region  580  defines substrate surface  532 , facet  530 , and tip region  586 . Tip region  586  is between facet  530  and the bottom surface of gate dielectric  544 . 
         [0083]    According to embodiments, tip regions  576  and  586  may extend under spacer  512 , spacer  514 , and/or gate electrode  590 . For example, tip regions  576  and  586  may extend along top surface  525  under the bottom surface of gate dielectric  544  from a width equal to width W 52  to a width of less than width W 52 , such as a width of greater than zero. Thus, facets  520  and  530  may contact the bottom surface of gate dielectric  544  adjacent to top surface  525  of substrate  505  to form a channel under top surface  525  between facets  520  and  530  (e.g., a channel of a transistor formed in apparatus  500 ), where facets  520  and  530  may each extend under gate dielectric  544  by a distance of between zero and one-half of width W 52 . Thus, portions of substrate  505  may be removed to form facets  520  and  530  contacting and extending under the bottom surface of gate dielectric  544  to contact the bottom surface of gate dielectric  544  under spacer  512 , spacer  514 , and/or gate electrode  590 . 
         [0084]    Junction region  570  and/or  580  may be referred to as “source/drain regions” or “diffusion regions.” Also, when an appropriate material is formed, deposited, or grown in junction regions  570  and  580 , the resulting material may be referred to as a “junction,” a “source,” a “drain,” or a “diffusion region.” 
         [0085]    Suitable chambers for etching junction regions  570  and  580  include those mentioned above with respect to forming gate dielectric  144 . Specifically, suitable chambers for etching junction regions  570  and/or  580  include a CVD chamber, an ALD chamber, a UHVCVD chamber, an RTCVD chamber, an RPCVD chamber, an MBE chamber, a “batch” UHV CVD chamber, a cold-wall UHV CVD chamber, an atmospheric pressure (AP) CVD chamber a low-pressure (LP) CVD chamber, an etch chamber, a high-purity high-flow hydrogen (H 2 ) purge reactor, a chlorine (Cl 2 ) etch chamber, a trisilane deposition reactor, a disilane deposition reactor, or a chamber reactor that combines the functionality of one or more of these chambers or reactors. 
         [0086]    Consequently, in  FIG. 5 , junction regions  570  and  580  may or may not correspond to junction regions  270  and  280 , surfaces  522  and  532  may or may not correspond to surfaces  222  and  232 , facets  520  and  530  may or may not correspond to facets  220  and  230 , and tip regions  576  and  586  may or may not correspond to tip regions  276  and  286  of  FIG. 2 , as described above. Specifically, in  FIG. 5 , junction regions  570  and  580  may or may not be formed by chlorine etching or other etching as described above with respect to junction regions  270  and  280 . Likewise, deposition of material into junction regions  570  and  580  of  FIG. 5  may or may not occur in the same chamber as the chamber in which junction regions  570  and  580  were formed or etched. Next, facets  520  and  530  of  FIG. 5  may or may not form an angle with respect to surfaces  522  and  532  similar to angle A 1  and angle A 2  as described with respect to  FIG. 2 . 
         [0087]      FIG. 6  is the schematic substrate of  FIG. 5  after forming a thickness of a crystalline material in the junction regions and a thickness of amorphous material on the gate electrode.  FIG. 6  shows apparatus  600  having conformal thickness  610  of amorphous material formed over etch mask  542 , spacers  512  and  514 , gate electrode  590 , and gate dielectric  544 . Herein, etch mask  542 , spacers  512  and  514 , gate electrode  590 , and gate dielectric  544  may be referred to as a “gate structure” (e.g., the gate structure of apparatus  500 ). Conformal thickness  610  is shown having thickness T 610  above etch mask  542 , thickness T 612  beside spacer  512  and thickness T 613  besides spacer  514 . 
         [0088]      FIG. 6  also shows epitaxial thickness  620  of a crystalline material in junction region  570  and having thickness T 620 . Likewise, epitaxial thickness  630  is formed injunction region  580  and has thickness T 630 . According to embodiments, thickness  610  (e.g., such as an amorphous layer) and epitaxial thickness  620  and  630  may be formed “simultaneously,” such as by deposition of those materials on apparatus  500  during the same period of time, by blanket deposition, and/or by non-selective deposition to form thickness  610 ,  620 , and  630  of apparatus  600 . Moreover, during simultaneous formation, the rate of forming conformal thickness  610  may be faster than the rate of forming epitaxial thicknesses  620  and  630   
         [0089]    For example, conformal thickness  610  and epitaxial thicknesses  620  and  630  may be formed by non-selective or “blanket” chemical vapor deposition (CVD) of the crystalline and amorphous materials. It is contemplated that epitaxial thickness  620  and  630  may be a silicon alloy or a silicon element material having a lattice spacing different than the lattice spacing of substrate  505 . In some embodiments, thicknesses  620  and  630  may be an epitaxial thickness of crystalline phosphorous and/or a silicon-carbon alloy material having a size, thickness, and lattice spacing to cause a tensile strain in substrate  505 . It is also contemplated that thicknesses  620  and  630  may be doped with phosphorous, arsenic, and/or antimony during or after formation, such as to form a N-type material having an electrically negative charge. Thus, thickness  620  and thickness  630  may cause a tensile strain in a channel of apparatus  600 , such as a region of substrate  505  below top surface  525  and between junction regions  578  and  580 . 
         [0090]    Conformal thickness  610  may be an amorphous material of the same silicon alloy or silicon element material used to form thickness  620  and  630 . Specifically, instead of being a epitaxial thickness, conformal thickness  610  may be a conformal thickness of the same material that forms thickness  620  and  630 . As such, conformal thickness  610  may be an amorphous layer with no definite arrangement of atoms in contrast to the very regular arrangement of atoms and crystalline material of thickness  620  and  630 . Also, conformal thickness  610  may have a lattice spacing that is different than that of the material etch mask  542 , spacers  512  and  514 , gate electrode  590 , and/or gate dielectric  544  (e.g., the gate structure of apparatus  500 ). Thus, conformal thickness  610  may cause a tensile strain in gate electrode  590  and/or other components of the gate structure of apparatus  500 . 
         [0091]    For example, thickness  610 ,  620 , and  630  may be formed (e.g., in the case where apparatus  600  is or will become a n-MOS transistor or device) of a silicon-carbon alloy film blanket or non-selective deposited over the active area of a transistor (e.g., deposited over apparatus  500 ). The deposition may be a chemical vapor deposition (CVD) using trisilane, methylsilane, and hydrogen (e.g., a H 2  carrier gas) had a deposition temperature of less than 550° C. (e.g., at a temperature of 450, 500, or 550° C.). In such a setting, epitaxial thickness  620  and  630  are rendered epitaxial on the exposed silicon or surface of junction regions  570  and  580 . Specifically, an epitaxial layer is formed on surface  522 , facet  520 , surface  532 , and facet  530 . Alternatively, in such a setting, an amorphous thickness is formed on the dielectric, oxide, or nitride of etch mask  542 , spacers  512  and  514 , gate electrode  590 , and gate dielectric  544  (e.g., the gate structure of apparatus  500 ). The epitaxial crystalline material formed as thickness  620  and  630  may be in-situ doped with phosphorous or arsenic during or after deposition to form N-type electrically negatively charged material. 
         [0092]    According to embodiments, thickness  610 ,  620 , and  630  may be formed by introducing trisilane at between 25 milligrams per minute (mg/min) and 200 mg/min, and introducing monomethyl silane at between 15 standard cubic centimeters (SCCM) and 45 SCCM, and introducing PH 3  (e.g., by introducing 1 percent PH 3  in a hydrogen (H 2 ) carrier gas) at between 400 SCCM and 800 SCCM. In another example, forming thicknesses  610 ,  620 , and  630  may include introducing between 50 and 100 mg/min of trisilane, 30 SCCM of monomethylsilane, and 600 SCCM of PH 3 . 
         [0093]    In one embodiment, in a single wafer 300 mm RT CVD reactor, a chemistry of 20 SCCM of trisilane, 30 SCCM of mono-methyl silane, 20 SLM of H 2 , at 550° C., and 15 Torr pressure for 12 minutes produces a 500 nano-meter silicon-carbon alloy film with a fully substituted carbon concentration of 3E20 cm cubed as epitaxial thickness  620  and  630 . Conformal thickness  610  of an amorphous material is formed in regions not in contact with the surfaces of junction regions  570  and  580  (e.g., regions not in contact with surface  522  and  532  or facet  520  and  530 ). Thus, conformal thickness  610  may be formed on etch mask  542 , spacers  512  and  514 , gate electrode  590 , and/or gate dielectric  544 . One reason for the formation of the crystalline material on surfaces  522  and  532  and facets  520  and  530  is that, on these surfaces, the silicon continues to grow by epitaxially expanding the existing lattice. However, since there is no existing silicon lattice to support growth on surfaces of etch mask  542 , spacers  512  and  514 , gate electrode  590 , and gate dielectric  544 , material formed there is of an amorphous nature. 
         [0094]    In some embodiments, epitaxial thickness  620  and  630  may be or include a silicon material having a substitutional-carbon concentration of between 0.13 percent and 2.0 percent. Also, in some embodiments, epitaxial thickness  620  and  630  may be or include a silicon material having a phosphorous concentration of between 5E13 atoms per centimeter cubed (atoms/cm) and 5E20 atoms/CM 3 . For example, epitaxial thickness  620  and  630  may be a silicon alloy or silicon elemental material having a substitutional-carbon concentration of between 0.13 percent and 2.0 percent, and having a phosphorous concentration of between 5E13 atoms per centimeter cubed (atoms/cm) and 5E20 atoms/CM 3 . 
         [0095]    Often, when blanket or non-selective deposition over the active area of a transistor (e.g., deposition over apparatus  500 ) is continued thickness  610 ,  620 , and  630  may be formed such that thickness  610  expands into the tip regions and/or onto the bottom surface of the gate electrode before thickness  620  and  630  expand to those locations. Specifically, if the deposition process described above with respect to  FIG. 6  is continued, it is possible that thickness T 612  and T 613  will continue to grow and that amorphous material of thickness  610  will expand into tip regions  576  and  586  (see  FIG. 5 ) and or onto bottom surface B 1  or bottom surface B 2  of gate dielectric  544  (see  FIG. 7 ). Having amorphous material of thickness  610  in the tip regions and/or on the bottom surface of the gate electrode inhibits performance of the transistor. Moreover, after thickness  620  and  630  have been formed to a height above surface  525 , etching away or removal of amorphous material of thickness  610  in the tip regions and/or on the bottom surface of the gate electrode leaves a device that does not function properly. 
         [0096]    However, according to embodiments, epitaxial thickness  610 ,  620  and  630  may be etched back prior to further deposition of material to expand thickness  610 ,  620  and  630 . For instance,  FIG. 7  shows the substrate of  FIG. 5  after removing a thickness of the crystalline material and a thickness of the amorphous material.  FIG. 7  shows apparatus  700 , such as an apparatus corresponding to apparatus  600  after a thickness of conformal thickness  610  and epitaxial thickness  620  and  630  are removed. For example, the amorphous material of conformal thickness  610  and the crystalline material of epitaxial thickness  620  and  630  may be removed simultaneously during a process, such as an etch process to form conformal thickness  710  and epitaxial thickness  720  and  730 , as shown in  FIG. 7 . Conformal thickness  710  as thickness T 710  above etch mask  542 , thickness T 712  adjacent to spacer  512 , and thickness T 713  adjacent to spacer  514 . Also, epitaxial thickness  720  has thickness T 720 , and epitaxial thickness  730  has thickness T 730 . According to embodiments a rate of removing or etching epitaxial thickness  720  and  730  may be slower than a rate of removing or etching conformal thickness  710 . For example, an etch chemistry may be selected that etches the crystalline material of thickness  720  and  730  slower than it etches the amorphous material of thickness  710 . Thus, removal of thicknesses  710 ,  720  and  730  may continue until a remaining vertical thickness of thickness  710  is less than a remaining thickness of thickness  720  and  730 . Specifically, thickness T 710  may be less than thickness T 720  or thickness T 730 . However, it is also contemplated that thickness T 710  may be equal to or greater than thickness T 720  and/or thickness T 730 . 
         [0097]    Moreover, according to embodiments, forming thickness  710  may include removing a thickness of thickness  610  sufficiently so that a subsequent forming or deposition of conformal material over thickness  710  does not extend onto or below bottom surface B 1  or bottom surface B 2  of gate dielectric  544 . For example, thickness T 712  and thickness T 713  may be sufficiently thin so that subsequent deposition of conformal thickness or amorphous material onto thickness  710  does not extend below or onto bottom surfaces B 1  and B 2 . 
         [0098]    Thickness T 720  and/or thickness T 730  may be a thickness of crystalline material between 0.5 nano-meters (nm) and 2 nm, such as 0.8, 0.9, 0.95, 1.0, 1.05, 1.1, 1.15, 1.2, 1.3, or 1.4 nm. Specifically, the net affect of forming thickness  610 ,  620 , and  630 , and removing thicknesses thereof to form thickness  710 ,  720  and  730  may define a formation rate of approximately 1.05 angstroms per second (e.g., 10 nm per minute) for epitaxial thickness  720  and  730 . A similar net effect may occur or the thickness  710  in the lateral direction, and may be a little higher in the vertical direction (e.g., in the direction of thickness T 710 ). 
         [0099]    Furthermore, in embodiments, removal of thicknesses of thickness  610 ,  620 , and  630  may occur at a rate, for a duration, or with an etchant such that thickness T 712  and T 713  is less than thickness T 720  or thickness T 730 . 
         [0100]    For example, removal of thicknesses of thickness  610 ,  620 , and  630  may include etching with hydrochloric acid, chlorine, or other appropriate etchants or gases. Specifically, such etching may include etching with a hydrochloric acid gas a flow rate of between 100 SCCM and 200 SCCM, such as at a flow rate of 140, 145, 150, 155, or 160 SCCM. It is also contemplated that a dry resist etch, chlorine etch, CF 4 , plasma, sputter, and/or other etch chemistry or gas capable of removing thicknesses of thickness  610 ,  620 , and  630  may be used. 
         [0101]    Moreover, according to embodiments, forming of thickness  610 ,  620 , and  630 , and removal of thicknesses thereof to form thickness  710 ,  720 , and  730  may occur in the same chamber for reactor without breaking a seal, vacuum, pressure, ambiance, of the chamber or reactor, and/or without exposing the inside of the chamber or reactor to the outside atmosphere or air. Thus, removal of thickness of material to form thickness  710 ,  720 , and  730  may be performed in-situ with forming of thickness  610 ,  620 , and  630 . Specifically, the simultaneous forming and removal of the thicknesses may occur at the same pressure, at the same temperature, in the same ambiance, in the same atmosphere, and/or during the same seal or vacuum of a chamber or reactor. For instance, some suitable chambers for forming of thickness  610 ,  620 , and  630 , and removal of thicknesses thereof to form thickness  710 ,  720 , and  730  in the same chamber include a CVD chamber, an ALD chamber, a UHVCVD chamber, an RTCVD chamber, an RPCVD chamber, an MBE chamber, a “batch” UHV CVD chamber, a cold-wall UHV CVD chamber, an atmospheric pressure (AP) CVD chamber a low-pressure (LP) CVD chamber, an etch chamber, a high-purity high-flow hydrogen (H 2 ) purge reactor, a chlorine (Cl 2 ) etch chamber, a trisilane deposition reactor, a disilane deposition reactor, or a chamber reactor that combines the functionality of one or more of these chambers or reactors. Further, appropriate chambers include chambers for performing deposition of epitaxial thicknesses of silicon, silicon alloy, and/or silicon elemental materials; chambers for deposition of conformal thickness of amorphous material; chambers for deposition of crystalline material, chambers for forming blanket or non-selective deposition; chambers for forming selective deposition, chambers for depositing doped material, chambers for depositing silicon germanium (SiGe) and/or chambers for depositing silicon-carbon alloy (Si x C 1-x ) material. 
         [0102]    In some embodiments, forming thickness  610 ,  620 , and  630  and removing thicknesses thereof may occur in the same CVD chamber, at a temperature of between 500 and 750° C. (e.g., at a temperature of 500, 550, 600, 650, 700, or 750° C.), and at a pressure of between 12 and 18 Torr (e.g., at a pressure of 12, 13, 14, 15, 16, 17, or 18 Torr). Also, forming thickness  610 ,  620 , and  630  and removing thicknesses thereof may occur in the same CVD chamber at a pressure of between 1E-4 and 1000 Torr (e.g., at a pressures within a one decimal range of 1E-3, 1E-2, 0.1, 1.0, 10, 100, or 1000 Torr). In some cases, forming thickness  610 ,  620 , and  630  and removing thicknesses thereof may occur in the same CVD chamber at a pressure of between 3E-3 Torr and 7E-3 Torr (e.g., 3E-3, 3.5E-3, 4E-3, 4.5E-3, 5E-3, 5.5E-3, 6E-3, 6.5E-3, or 7E-3). Moreover, there may be a hydrogen (H 2 ) ambient flow of between ten standard liters per minute (SLM) and 30 SLM during the forming and removing. 
         [0103]    In some embodiments, forming, depositing, or growing thickness  610 ,  620 , and  630 ; and then removing, or etching a thickness of thickness  610 ,  620 , and  630  as described above with respect to  FIGS. 6 and 7  may describe one iteration or deposition/removal sequence of a multiple iteration process. Thus, the iteration or deposition/removal sequence of  FIGS. 6 and 7  may be repeated. 
         [0104]    For example,  FIG. 8  shows the substrate of  FIG. 7  after forming a subsequent thickness of a crystalline material in the junction regions and a subsequent thickness of the amorphous material on the gate electrode.  FIG. 8  shows apparatus  800 , such as apparatus  700  after reforming or redepositing additional conformal thickness of amorphous material on thickness  710  to form thickness  810 , redepositing or depositing additional epitaxial thickness of crystalline material on thickness  720  to form thickness  820 , and redepositing or depositing additional epitaxial thickness of crystalline material on thickness  730  to form epitaxial thickness  830 . Thus, thickness T 810  of conformal thickness  810  may be thicker than thickness T 610  or T 710 . Similarly, thickness T 812  may be thicker than thickness T 712  or T 612 . Likewise, thickness T 813  may be thicker than T 713  or T 613 . 
         [0105]    Similarly, thickness T 820  of epitaxial thickness  820  may be thicker than thickness T 720  or T 620 . Likewise, thickness T 830  of epitaxial thickness  830  may be thicker than thickness T 730  or T 630 . 
         [0106]    It is contemplated that conformal thickness  810  may include material, be formed by a process, have a functionality, and cause strains as described above with respect to conformal thickness  610 . Similarly, epitaxial thickness  820  and  830  may correspond to material, be formed by processes, cause strains, and have functionality as described above with respect to epitaxial thickness  620  and  630 . 
         [0107]    Subsequent to forming apparatus  800 , thicknesses of thickness  810 ,  820 , and  830  may be removed, such as by etching. For example,  FIG. 9  shows the substrate of  FIG. 8  after removing a thickness of the crystalline material and the amorphous material.  FIG. 9  shows apparatus  900 , such as apparatus  800  after removing thicknesses of thickness  810 ,  820 , and  830  to form conformal thickness  910  of amorphous material, epitaxial thickness  920  of crystalline material, and epitaxial thickness  930  of crystalline material. Thus, materials, processes, functionality, and strains of thickness  910 ,  920 , and  930  may correspond to those described above with respect to thickness  710 ,  720 , and  730 . It can also be appreciated that the relationship between thickness  910 ,  920 , and  930 , as compared to thickness  810 ,  820 , and  830  may correspond to the relationship between thickness  710 ,  720 , and  730  as compared to thickness  610 ,  620 , and  630 . Specifically, processes for forming apparatus  800  from apparatus  700  and subsequently forming apparatus  900  from apparatus  800  may correspond to those described above for forming apparatus  600  from apparatus  500  and subsequently forming apparatus  700  from apparatus  600 . 
         [0108]    Moreover, according to embodiments, processes for forming apparatus  600 ,  700 ,  800 , and  900  may occur in the same chamber, such as without breaking a seal or vacuum of a chamber, and/or under other settings or conditions as described above with respect to forming apparatus  700  from apparatus  600 . Thus, formation of apparatus  600  and  700  may be defined as a first iteration, and forming apparatus  800  and  900  may be defined as a second iteration in a process for deposit/removal iterations. Such iterations may be continued until a desired or selected thickness of an epitaxial crystalline material is formed in the junction regions of the transistor device. Also, such iterations may be continued until a desired or selected thickness of a conformal amorphous material over the gate structure of a transistor device. In some cases, such iterations may be repeated between five and ten times, such as by being repeated five times, six times, seven times, eight times, nine times, or ten times. 
         [0109]    It is also contemplated that such iterations may terminate with a deposition or a removal process (e.g., a process corresponding to forming apparatus  600  or apparatus  700 ). Likewise the deposition or removal portions of the iteration may occur over a period of between five seconds and five minutes, such as where each deposition and/or removal process occurs over a period of ten seconds, 20 seconds, 25 seconds, 30 seconds, 35 seconds, 40 seconds, 45 seconds, 50 seconds, 60 seconds, or 90 seconds. 
         [0110]    In one example, forming of thickness  610 ,  620 , and  630  may be performed in-situ with removal of thicknesses of material to form thickness  710 ,  720 , and  730  in CVD chamber. First, thickness  610 ,  620 , and  630  are formed or deposited by introducing trisilane at between 50 mg/min and 100 mg/min, introducing monomethyl silane at 30 SCCM, and introducing PH 3  (e.g., one percent PH 3  in a H 2 ) at 600 SCCM for 30 seconds while of H 2  is introduced into the chamber at a flow of 20 SLM, the chamber is kept at a temperature of between 600 and 650 degrees Celsius, and the chamber is at a pressure of 15 Torr. 
         [0111]    Next, thickness  710 ,  720 , and  730  are formed “immediately” after deposition of thickness  610 ,  620 , and  630  (e.g., no other processing is performed between pumping out the deposition gases used to form thickness  610 ,  620 , and  630  and etching thickness  610 ,  620 , and  630  to from thickness  710 ,  720 , and  730 ). For instance, thickness  710 ,  720 , and  730  are formed by etching thickness  610 ,  620 , and  630  by introducing HCl at 150 SCCM into the chamber for 30 seconds while of H 2  is introduced into the chamber at a flow of 20 SLM, the chamber is kept at a temperature of between 600 and 650 degrees Celsius, and the chamber is at a pressure of 15 Torr. 
         [0112]    The sequence of introducing trisilane, monomethyl silane, and PH 3 , pumping out, and then introducing HCl is repeated 7 times to form about 1.05 angstroms/sec in thickness (deposition minus etch) for crystalline material of thickness  720 , and  730 . The thickness of thickness  710  of amorphous material is about the same in the lateral direction (e.g., thickness T 712  and T 714 ), but is a little more in the vertical direction (e.g., thickness T 710 ). Moreover, it can be appreciated that the seal or vacuum of the chamber can be kept in tact during the 7 iterations. Similarly, the conditions where H 2  is introduced into the chamber at a flow of 20 SLM, the chamber is kept at a temperature of between 600 and 650 degrees Celsius, and the chamber is at a pressure of 15 Torr may be maintained during the 7 iterations. 
         [0113]    Thus, it is possible to repeat iterations of forming and removal of the conformal and epitaxial thicknesses until a top surface of the epitaxial thicknesses is superior to top surface  525 , and/or until the epitaxial thicknesses cause a selected strain in substrate  505 . For example,  FIG. 10  shows the substrate of  FIG. 9  after forming a thickness of crystalline material in the junction regions to form junctions, and after forming a thickness of amorphous material on the gate electrode.  FIG. 10  shows apparatus  1000  having conformal thickness  1010  of amorphous material over the gate structure and epitaxial thickness  1020  and  1030  injunction regions  570  and  580 . Thickness  1020  has top surface  1022  superior to top surface  525 , and thickness  1030  has top surface  1032  superior to top surface  525 .  FIG. 10  also shows thickness  1020  having thickness T 1020 , and thickness  1030  having thickness T 1030 . 
         [0114]    It can be appreciated that conformal thickness  1010  may be formed of a material by processes, have a functionality and cause strains as described above with respect to conformal thickness  610 . Similarly, epitaxial thicknesses  1020  and  1030  may be formed of a material, by a process, have a functionality, and/or cause strains as described above with respect to epitaxial thickness  620  and  630 . For example, thickness  1020  and  1030  may be a sufficient thickness or size of a crystalline material having a lattice spacing different than the lattice spacing of new material of substrate  505  to cause a strain in substrate  505 , such as a strain in the channel of apparatus  1000  (e.g., where the channel may be defined as the portion of substrate  505  below top surface  525  and between thicknesses  1020  and  1030 ). Moreover, thickness  1020  and  1030  may be epitaxial thicknesses of crystalline phosphorous and/or silicon-carbon alloy material, sufficient to cause a tensile strain in substrate  505 . 
         [0115]    Specifically, as shown in  FIG. 10 , thickness  1020  may cause tensile strain  1074  away from a portion of substrate  505  under top surface  525 , and thickness  1030  may cause tensile strain  1084  away from the same portion of substrate  505 . Thus, strain  1074  may cause tensile strain  1092 , and strain  1084  may cause tensile strain  1094  in a channel of substrate  505  between thickness  1020  and  1030  (e.g., a tensile strain in the channel of apparatus  1000 , or apparatus  1000  is a n-MOS device). According to embodiments, tensile strains  1092  and  1094  may be sufficient strains to increase carrier mobility (e.g., mobility of electrons in the channel of well  524 ) between thickness  1020  and  1030 . In other words, a channel in substrate  505  may be under a tensile strain caused by the lattice spacing of a phosphorous and/or silicon-carbon alloy material in thickness  1020  and  1030  being larger than the lattice spacing of the substrate material. 
         [0116]    Also, as described above, with respect to conformal thickness  610 , conformal thickness  1010  may cause a tensile strain in the gate structure of apparatus  1000 , such as a tensile strain in gate electrode  590 . 
         [0117]      FIG. 10  also shows epitaxial thickness  1020  filling tip region  576 , and epitaxial thickness  1030  filling tip region  586 . For example, thickness  1020  may be in contact with and/or atomically bonded to bottom B 1  and facet  520 . Similarly, thickness  1030  may be attached to and/or atomically bonded bottom B 2  and/or facet  530 . 
         [0118]    It is also considered that thickness  1020  and thickness  1030  may be doped during or after formation with phosphorous, arsenic, and/or antimony to form an N-type material having an electrically negative charge. 
         [0119]    For example, once a sufficient or selected thickness of material is deposited or formed as thickness  1020  and  1030  (e.g., after a deposition or etch portion of an iteration) conformal thickness  1010  may be removed. Thus, conformal thickness  1010  of  FIG. 10  may be removed from the gate structure of apparatus  1000 , such as by selective wet etch. Moreover, a conformal amorphous thickness (e.g., thicknesses  610 ,  710 ,  810 ,  910  and  1010  described above, may be left on isolation material (e.g., material  510 ) as well. These conformal amorphous thicknesses may also be removed, such as by selective wet etch, thus resulting in a tensile strained N-channel transistor which has increased electron mobility and drive current. 
         [0120]    For example,  FIG. 11  shows the substrate of  FIG. 10  after removing the amorphous materials.  FIG. 11  shows apparatus  1100 , such as apparatus  1000  after removing or etching conformal thickness  1010  from the gate structure of apparatus  1000 . For example, conformal thickness  1010  may be selectively or non-selectively etched using an etch chemistry that leaves an appropriate thickness of epitaxial material in junction region  570  and  580 , such as thickness  1120  and  1130 . In some embodiments, etching conformal thickness  1010  from the gate structure includes etching a thickness of between five percent and 35 percent of the thickness of thickness  1020  and  1030 . Thus, after etching conformal thickness  1010  from the gate structure thickness  1120  and  1130  may be 75, 80, 75, or 90 percent as thick as thickness  1020  and  1030  as described above for  FIG. 10 . Similarly, top surface  1122  and  1132  may correspond to top surface  1022  and  1032  as described above for  FIG. 10 . Furthermore, thickness T 1120  and T 1130  may correspond to thickness T 1020  and thickness T 1030  as described above for  FIG. 10 . 
         [0121]    After removal of thickness  1010 , the remaining transistor (e.g., apparatus  1100 ) may have strains  1174 ,  1184 ,  1192 , and  1194  which may correspond to or be greater in magnitude than strains  1074 ,  1084 ,  1092 , and  1094  of  FIG. 10 . It is also appreciated that strains  1174 ,  1184 ,  1192 , and  1194  may correspond to or have directions similar to strains  1074 ,  1084 ,  1092 , and  1094  of  FIG. 10 . Specifically, strains  1174 ,  1184 ,  1192 , and  1194  may correspond to or be within thirty percent in magnitude and ten degrees direction of strains  1074 ,  1084 ,  1092 , and  1094  of  FIG. 10 . 
         [0122]    Thus, strains  1174 ,  1184 ,  1192 , and  1194  may cause a sufficient tensile strain in the channel of apparatus  1100  to increase electron mobility and drive current. Moreover, strain  1192  and  1194  may be uniaxial tensile strain caused by increased phosphorous and substitutional-carbon concentration in epitaxial thickness  1120  and  1130 . Also, increased phosphorous doping in epitaxial thickness  1120  and  1130  may be greater than the 2E20 cm cubed. Specifically, apparatus  1100  may be a n-MOS transistor with a sufficient increased phosphorous and substitutional-carbon concentration in epitaxial thickness  1120  and  1130  to increase carrier mobility and reduce R External . Overall, a transistor similar to apparatus  1100  may have improved saturation current and improved device speed due to the gain in carrier mobility and due to decreased sheet resistant in epitaxial thickness  1120  and  1130 . 
         [0123]    Thus, apparatus  1100  may be an n-MOS device of a CMOS device. For example,  FIG. 12  shows a representative CMOS structure.  FIG. 12  shows CMOS device  1200  having n-MOS device  1202 , such as an embodiment of apparatus  1100  as described above with respect to  FIG. 11 , connected to p-MOS device  1204  in typical fashion. Substrate  505  includes P-type well  524  related to N-type well  1224  for forming CMOS device  1200 , such that N-type well  1224  is part of p-MOS transistor device  1204  formed on a second area of substrate  505  and defining a second different interface surface  1225  of substrate  505  adjacent to P-type well  524 . Specifically, for instance, p-MOS device  1204  may be formed adjacent to n-MOS device  1202  by having p-MOS device  1204  electrically isolated from n-MOS device  1202  by electrically insulating material  510  as described herein. Moreover, p-MOS device  1204  may include a channel below gate dielectric  1244  which is below gate electrode  1290 , and between P-type junctions  1220  and  1230 . p-MOS device  1204  is also shown with spacers  1212  and  1214 . 
         [0124]      FIG. 12  also shows compressive strains  1274 ,  1284 ,  1292 , and  1294  and p-MOS device  1204 . For example, junctions  1220  and  1230  may cause compressive strains  1274  and  1284  towards a portion of substrate  505  under top surface  1225 . Thus, strains  1274  and  1284  may cause compressive strains  1292  and  1294  in a channel of p-MOS device  1204 . It can be appreciated that compressive strains  1292  and  1294  may be sufficient to increase carrier mobility (e.g., mobility of holes in the channel of well  1224 ) between junctions  1220  and  1230 . Specifically, junctions  1220  and  1230  may be formed of a material having a lattice spacing larger than a lattice spacing of substrate  505  (e.g., by being formed of SiGe, which may or may not be doped with boron and/or aluminum to form a P-type electrically positive charged material). Finally, CMOS device  1200  has ground GND, input voltage V in , output voltage V out , and bias voltage V DD . 
         [0125]    In the foregoing specification, specific embodiments are described. However, various modifications and changes may be made thereto without departing from the broader spirit and scope of embodiments as set forth in the claims. The specification and drawings are, accordingly, to be regarded in an illustrative rather than a restrictive sense.