Patent Publication Number: US-8523639-B2

Title: Self cleaning and adjustable slurry delivery arm

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
     This application claims benefit of U.S. Provisional Patent Application Ser. No. 61/110,434, filed Oct. 31, 2008, which is herein incorporated by reference. 
    
    
     BACKGROUND OF THE INVENTION 
     1. Field of the Invention 
     Embodiments of the invention relate to an apparatus and a method for polishing of substrates, and more particularly to a slurry dispenser and rinse arm and methods for thereof. 
     2. Description of the Related Art 
     Integrated circuits are typically formed on substrates by the deposition of conductive, semi-conductive, or insulative layers. After each layer is deposited, the layer is etched to create circuitry features. As a series of layers are sequentially deposited and etched, the uppermost exposed surface of the substrate may become non-planar and requires planarization. This non-planar surface occurs when the thickness of the layers formed on the substrate varies across the substrate surface as a result of the nonuniform geometry of the circuits formed thereon. In applications having multiple patterned underlying layers, the height difference between the peaks and valleys becomes even more severe, and may be several microns. 
     Chemical mechanical polishing (CMP) is a planarization process which involves wetting a rotatable polishing pad with a chemical slurry containing abrasive components and mechanically polishing the front surface of the substrate against the wetted pad. The pad is mounted on a rotary platen and a rotatable substrate carrier is used to apply a downward pressure against the backside of the substrate. The polishing slurry is dispensed onto the pad through a slurry dispensing arm during polishing. The force between the carrier and the pad and their relative rotation, in combination with the mechanical and chemical effects of the slurry, serve to polish the substrate surface. 
       FIG. 1  depicts CMP system  10  in which a substrate  38  is held by a carrier head  46  which rotates about the central axis of the substrate  38 . A circular polishing pad  40  is rotated while in contact with the bottom surface of the rotating substrate  38  being held by the carrier head  46 . The rotating substrate  38  contacts the rotating polishing pad  40  in an area away from the center of the polishing pad  40 . A slurry delivery arm  15  positioned above the surface of the polishing pad  40  dispenses a slurry  17 , including, for example, an abrasive and at least one chemically-reactive agent, on the polishing pad  40  by way of a supply circuit  14  and  16 . The slurry  17  is delivered to the center of the polishing pad  40  to chemically passivate or oxidize layers on the surface of the substrate being polished and abrasively remove or polish off select layers. A reactive agent in the slurry reacts with the film on the surface of the substrate to facilitate polishing. The interaction of the polishing pad, the abrasive particles, and the reactive agent with the surface of the substrate results in controlled polishing of the desired layers. 
     One problem encountered in CMP is that the slurry delivered to the polishing pad may coagulate, and along with the material being removed from the substrate, clog the grooves or other features on the pad thereby reducing the effectiveness of the subsequent polishing steps and increasing the likelihood of poor defect performance. Accordingly, rinse arms have been incorporated in some CMP systems to deliver water or rinse solutions to the pad to facilitate rinsing of the coagulated slurry and other materials from the grooves of the pad. 
     However, CMP systems encountered several drawbacks. First, the slurry delivery line often becomes clogged by condensed slurry inside the line. In addition, the rinse arm is usually in a fixed position over the pad therefore can only dispense to one location at a time. Still further, the rinse arm must be disposed over the center of the pad in order to deliver the rinse agent to that portion of the pad. Depending on the location of the substrate carrier head relative to the pad, rinsing of the central portion of the pad may not be accomplished unless the substrate carrier head is moved from the pad and polishing steps are discontinued. 
     Therefore, there exists a need to provide a slurry delivery and rinse system which is capable of self-cleaning, and which can adjustably deliver the slurry agent and rinse agent over the entire surface of the polishing pad without having to be located over the entire pad. 
     SUMMARY OF THE INVENTION 
     Embodiments of the invention provide a slurry delivery and rinse system for a chemical mechanical polishing (CMP) apparatus which is capable of self-cleaning, and which can adjustably deliver the slurry agent and rinse agent over the entire surface of the polishing pad without having to be located over the entire pad. In one embodiment, the apparatus for delivering fluids is provided which includes a delivery arm rotatably connected to a base and extending in a radial direction from the base, at least one slurry delivery line extending at least partially along the length of the delivery arm, at least one rinse agent delivery line extending at least partially along the length of the delivery arm, and a hinge assembly disposed on the delivery arm. 
     The apparatus may further contain at least one nozzle disposed downwardly on the delivery arm and connected to the at least one rinse agent delivery line. The at least one nozzle may be mounted at a perpendicular angle from a horizontal plane of the delivery arm. The tip of each nozzle may have an angle within a range from about 30° to about 60° relative to the horizontal plane of the delivery arm. In one example, the tip of each nozzle may have an angle of about 45°. In some examples, the manifolds and/or nozzles are made from or contain a fluorine-containing polymeric material, such as perfluoroalkoxy (PFA), fluorinated ethylene propylene (FEP), polytetrafluoroethylene (PTFE), or derivatives thereof. 
     In another embodiment, the apparatus for delivering fluids to a surface is provided which includes a fixed portion of a fluid delivery arm supported on a base at one end, at least one rinse agent delivery line disposed along at least a portion of the length of the fluid delivery arm, at least one slurry delivery line disposed at least partially along a portion of the length of the fluid delivery arm, and an adjustable portion of the fluid delivery arm connected to the fixed portion by a hinge. The hinge may further contain a plunger to secure the predetermined position of the delivery arm, a stopper to prevent over rotation of the delivery arm, and a hinge pin to connect the fixed block of an adjustable portion of the delivery arm to a hinge block of a fixed portion of the delivery arm. Alternatively, the hinge may further contain a fixed block connected to the adjustable portion, a hinge block connected to the fixed portion, and a hinge pin, wherein the hinge pin connects the fixed block of the adjustable portion to the hinge block of the fixed portion. The hinge may have a locking mechanism, such as a clamp, to secure the delivery arm to a particular position. The fixed portion may contain a rotatable shaft attached to the base, at least one spacer block to extend the length of the fixed portion, at least one first valve for use with the at least one rinse agent delivery line, and a first cover covering the at least one first valve. 
     In other embodiments, the adjustable portion of the hinge may have at least one second valve to receive slurry from the at least one slurry delivery line, a rinsing port to receive rinse agent through the at least one rinse agent delivery line from the at least one first valve in the fixed portion, a second cover to collect moisture from the at least one second valve, at least one nozzle mounted to the lower surface of the delivery arm, at least one delivery channel for the at least one slurry agent delivery line, and at least one opening for the at least one rinse agent delivery line. In one example, the at least one first valve is a solenoid and at least one second valve is a solenoid or a T-joint valve. Moisture may be contained by an angled top surface of the second cover. Examples provide that the slurry delivering line is connected to each nozzle via a delivery channel. In one example, the delivery channel may contain a blocking stud disposed in one end of the delivery channel. Many of these aforementioned parts may be made from or contain various plastics. For example, the blocking stud may contain polyetherethylketone, the rotatable shaft may contain polypropylene, the fixed block may contain polypropylene, the hinge block may contain polyetherethylketone, and the spacer block may contain polypropylene. 
    
    
     
       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 the invention and are therefore not to be considered limiting of its scope, for the invention may admit to other equally effective embodiments. 
         FIG. 1  depicts a side view of a chemical mechanical polishing apparatus known in the art; 
         FIG. 2  depicts a chemical mechanical polishing system containing fluid delivery system, as described in one embodiment herein; 
         FIGS. 3A-3C  depict schematic views of a delivery arm according to embodiments described herein; 
         FIGS. 4A-4B  depict a series of nozzles disposed on the lower surface of the delivery arm according to embodiments described herein; 
         FIGS. 5A-5B  depict cross sectional views of nozzles on a manifold according to embodiments described herein; 
         FIGS. 6A-6B  depict schematic views of a delivery arm containing a hinge according to another embodiment described herein; and 
         FIG. 7  depicts a multi-pad system according to an embodiment described herein. 
     
    
    
     DETAILED DESCRIPTION 
     Embodiments of the invention provide a slurry delivery and rinse system for a chemical mechanical polishing (CMP) apparatus which is capable of self-cleaning, and which can adjustably deliver the slurry agent and rinse agent over the entire surface of the polishing pad without having to be located over the entire pad. In one embodiment, the fluid delivery system has a distributed slurry delivery arm (DSDA) which contains at least one manifold, usually two or more manifolds attached to the lower surface of the delivery arm. Each DSDA manifold contains a plurality of slurry nozzles disposed along the length of the manifold and the delivery arm. The delivery arm also contains a plurality of high pressure rinse nozzles extending from the lower surface of the delivery arm and disposed along the length of the delivery arm, parallel to each DSDA manifold. In one example, the delivery arm contains two DSDA manifolds disposed parallel to each other and a plurality of high pressure rinse nozzles disposed between the manifolds. 
     In another embodiment, the DSDA manifolds distribute slurry to the pad or substrate from the slurry nozzles extending from the manifolds during a polishing process. Water or another rinse agent may be delivered to the pad from the high pressure rinse nozzles during a rinse process. Subsequently, the water or rinse agent may be diverted by a valve, and instead of passing through the high pressure rinse nozzles, the water or other rinse agent may pass through the slurry nozzles. In one example, the water or rinse agent is diverted by a non-return valve or one-way valve disposed at one end of a T-joint fitting coupled between the rinse agent delivery line, the slurry delivery line, and the source of the rinse agent. Alternatively, a three-way valve may be used of the non-return valve and T-joint fitting. The water or other rinse agent removes any residues, particulate, or other contaminants within the DSDA manifold and the slurry nozzles. 
     In other embodiments, the adjustable delivery arm which is rotatably mounted adjacent the surface to which it is intended to deliver the rinse agent and/or slurry. This position provides easy access to the surface for replacement and or other maintenance. Additionally, sweeping nozzles may be disposed on the fluid delivery system, specifically on the delivery arm. The sweeping nozzles may be used to direct rinse agent and debris toward and off the edge of the surface being cleaned. 
       FIG. 2  depicts a plan view of a chemical mechanical polishing (CMP) system  100  as described in an embodiment herein. The exemplary CMP system  100  generally comprises a factory interface, a loading robot  104 , and a polishing module  106 . The loading robot  104  is disposed proximate the factory interface and the polishing module  106  to facilitate the transfer of substrates  122  therebetween. 
     A controller  108  is provided to facilitate control and integration of the modules of the system  100 . The controller  108  comprises a central processing unit (CPU)  110 , a memory  112 , and support circuits  114 . The controller  108  is coupled to the various components of the CMP system  100  to facilitate control of, for example, the polishing, cleaning, and transfer processes. 
     The polishing module  106  includes at least a first CMP station  128 , disposed in an environmentally controlled enclosure  188 . The fluid delivery systems, as described herein, may be used in the CMP systems, such as, the MIRRA® CMP system, the MIRRA MESA® CMP system, the MIRRA® TRAK CMP system, and the MIRRA® DNS CMP system available from Applied Materials, Inc., located in Santa Clara, Calif. Other polishing modules, including those that use processing pads, polishing webs, or a combination thereof, and those that move a substrate relative to a polishing surface in a rotational, linear or other planar motion may also be adapted to benefit from the invention. 
     In the embodiment depicted in  FIG. 2 , the polishing module  106  includes one bulk CMP station  128 , a second CMP station  130  and a third CMP station  132 . Bulk removal of conductive material from the substrate is performed through an electrochemical dissolution process at the bulk CMP station  128 . After the bulk material removal at the bulk CMP station  128 , residual conductive material is removed from the substrate at the residual CMP station  130  through a second electrochemical mechanical process. It is contemplated that more than one residual CMP station  130  may be utilized in the polishing module  106 . A CMP process may be performed at the polishing station  132  after processing at the residual CMP station  130  by the barrier removal process described herein. Further disclosure of CMP processes for barrier removal is described in U.S. Pat. No. 7,104,869, which is incorporated by reference in its entirety. Each of the first and second CMP stations  128  and  130  may be utilized to perform both the bulk and multi-step conductive material removal on a single station. It is also contemplated that all CMP stations (for example 3 stations of the module  106  depicted in  FIG. 2 ) may be configured to process the conductive layer with a two step removal process. 
     The exemplary polishing module  106  also includes a transfer station  136  and a carousel  134  that are disposed on an upper or first side  138  of a machine base  140 . In one embodiment, the transfer station  136  includes an input buffer station  142 , an output buffer station  144 , a transfer robot  146 , and a load cup assembly  148 . The input buffer station  142  receives substrates from a factory interface by means of the loading robot  104 . The loading robot  104  is also utilized to return polished substrates from the output buffer station  144  to the factory interface. The transfer robot  146  is utilized to move substrates between the buffer stations  142 ,  144  and the load cup assembly  148 . In one example, the two transfer stations  144  and  146  are used with 200 mm diameter substrates. However, in another example, only one transfer station, such as transfer station  142 , is used with 300 mm diameter substrates. 
     In one embodiment, the transfer robot  146  includes two gripper assemblies (not shown), each having pneumatic gripper fingers that hold the substrate by the edge of the substrate. The transfer robot  146  may simultaneously transfer a substrate to be processed from the input buffer station  142  to the load cup assembly  148  while transferring a processed substrate from the load cup assembly  148  to the output buffer station  144 . An example of a transfer station that may be used to advantage is described in U.S. Pat. No. 6,156,124, which is herein incorporated by reference in its entirety. 
     The carousel  134  is centrally disposed on the base  140 . The carousel  134  typically includes a plurality of arms  150 , each supporting a polishing head assembly  152 . Two of the arms  150  depicted in  FIG. 2  are shown in phantom such that the transfer station  136  and a polishing surface  126  of the first CMP station  128  may be seen. The carousel  134  is indexable such that the polishing head assemblies  152  may be moved between the polishing stations  128 ,  130 ,  132  and the transfer station  136 . One carousel that may be utilized to advantage is described in U.S. Pat. No. 5,804,507, which is hereby incorporated by reference in its entirety. 
     Conditioning devices  182  may be disposed on the base  140  adjacent each of the polishing stations  130  and  132 , as depicted in  FIG. 2 . The conditioning devices  182  may be used to periodically supplement the polishing solutions at the stations  130   132  to maintain uniform polishing results. In an alternative embodiment, the conditioning devices  182  may be replaced with additional fluid delivery systems and/or arms, such as fluid delivery system  200  containing a distributed slurry delivery arm (DSDA)  202 , as well as a pad conditioning arm  201 . 
       FIGS. 3A-3C  depict schematic views of the delivery arm  202  used in the fluid delivery system  200  according to embodiments herein. The delivery arm  202  has a fixed portion  204  and an adjustable portion  208 , both connected to a hinge assembly  206 . The adjustable portion  208  may be moved to different locations of the pad or substrate by turning the hinge assembly  206 . The fixed portion  204  is mounted on a shaft  210  to enable rotation of the delivery arm  202  between a processing position over the polishing pad and a maintenance position adjacent the pad. The delivery arm  202  is generally angled along its length from its fixed portion  204  to its adjustable portion  208 . The delivery arm  202  may be adjustable to different angles according to process specifications through the use of the hinge assembly  206 . 
     In one embodiment, the shaft  210  may contain or be made of polypropylene. The cover  214  may contain or be made of nylon. The hinge assembly  206 , which includes a plunger  230 , a stopper  232 , and a hinge pin  234 , uses a locking mechanism to connect the fixed portion  204  to the adjustable portion  208 . The hinge assembly  206  allows the adjustable portion  208  to be turned and set to a desired position so that the position for slurry delivery may be adjusted according to pad size, location, or process parameters. 
     In one embodiment, the delivery arm  202  contains at least one manifold, usually two or more manifolds attached to the underside or lower surface  222  of the delivery arm  202 .  FIGS. 3A-3C  depict the delivery arm  202  having manifolds  302  and  304 . Both manifolds  302  and  304  have a plurality of slurry nozzles  224  disposed along the length of each other and extending away from the delivery arm  202  and towards the polishing pad. The delivery arm  202  also contains a plurality of high pressure rinse nozzles  310  and  312  extending away from the lower surface  222  of the delivery arm  202  towards the polishing pad. The plurality of high pressure rinse nozzles  310  and  312  are disposed along the length of the delivery arm  202  in a line which extends parallel to and between the manifolds  302  and  304 , as depicted in  FIGS. 3B-3C . 
     High pressure rinse nozzle  312  is disposed at the end of the adjustable portion  208  of the delivery arm  202 , opposite of the fixed portion  204 . High pressure rinse nozzle  312  may be adjusted or pivoted to spray rinsing agent at a wide range of angles. Delivery arm  202  may also contain a plurality of outlets  320  disposed on the lower surface  222 . The outlets may be at the end of the adjustable portion  208  of the delivery arm  202  in the vicinity of high pressure rinse nozzle  312 . In one example, high pressure rinse nozzle  312  may be disposed between four outlets  320  at the end of the adjustable portion  208 , as depicted in  FIG. 3C . 
     In another embodiment, the fixed portion  204  of the delivery arm  202  includes a valve or solenoid  212  enclosed by the cover  214 , as depicted in  FIG. 3A . The solenoid  212  is located on the fixed portion  204  and coupled to and in fluid communication with tubing throughout the delivery arm  202 . The solenoid  212  may be used to deliver rinsing agents such as deionized water. 
     In another embodiment, the delivery arm  202  may have one, two, or more slurry delivery lines mounted on or disposed within the delivery arm  202 . Usually, the delivery arm  202  contains a slurry delivery line for each DSDA manifold contained thereon.  FIG. 3A  depicts slurry delivery lines  213   a  and  213   b  coupled to and in fluid communication with valves or solenoids  216  and  218  positioned on the adjustable portion  208 . The other ends of the slurry delivery lines  213   a  and  213   b  may be coupled to and in fluid communication with the same or different source, such as a slurry reservoir. The solenoids  216  and  218  are independently two-way valves which are capable of two-way flowing. 
     In other embodiments, the manifolds  302  and  304  distribute slurry to the pad or substrate from the nozzles  224  and end nozzles  226  extending from the manifolds  302  and  304  during a polishing process. Water or another rinse agent may be delivered to the pad from the high pressure rinse nozzles  310  and  312  during a rinse process. Subsequently, the water or rinse agent may be diverted by solenoids  216  and  218  or another two-way valve, and instead of passing through the high pressure rinse nozzles  310  and  312 , the water or other rinse agent may pass through the nozzles  224  and end nozzles  226 . In one example, the water or rinse agent is diverted by the solenoids  216  and  218 . In another example, the water or rinse agent is diverted by a non-return valve or one-way valve disposed at one end of a T-joint fitting coupled between the rinse agent delivery line, the slurry delivery line, and the source of the rinse agent. Alternatively, a two-way valve or a three-way valve may is used to divert the water or rinse agent to the nozzles  224  and end nozzles  226 , instead of flowing through the high pressure rinse nozzles  310  and  312 . The water or other rinse agent removes any residues, particulate, or other contaminants within the DSDA manifold and the slurry nozzles. 
     In one embodiment, the T-joint fitting  221  may be connected to the solenoid  212  on the fixed portion  204  for cleaning purposes. Rinse agent, such as deionized water, may flow from line  217 , through the T-joint fitting  221 , and to the rinse agent delivery lines  217   a  and  217   b  for cleaning and rinsing the debris within the slurry delivery line. In another embodiment, tubing may be used as the slurry delivery lines and one or more slurries are pumped from one or more slurry sources using a diastolic pump or some other type of pump through the end of the tubing. A central rinse agent delivery line  217  is coupled between the solenoid  212  and the T-joint fitting  221 . A rinsing port  220  is located on the adjustable portion  208  and receives the rinse agent through the rinse agent delivery line  247  from the solenoid  212  and delivers one or more rinse agents to a plurality of nozzles  224  and an end nozzle  226  mounted to the lower surface  222  of the delivery arm  202 . 
     The adjustable portion  208  includes a cover  215  which collects the moisture coming out of the solenoids  216  and  218  and prevents the moisture from leaking. The cover  215  may contain or be made of nylon. The top surface  250  of the cover  215  may be sloped at an angle to prevent moisture settlement. The adjustable portion  208  preferably terminates at a position short of the center of where the carrier are being held to allow the carrier holding the substrate to move radially across or even over the center of the carrier holder (not shown) during polishing without the risk of having the delivery arm  202  collide with the carrier. 
     Each nozzle  224  and end nozzle  226  are disposed on the adjustable portion  208  of the delivery arm  202  at an angle to the plane of the delivery arm  202  to deliver one or more rinse agents. Alternatively, the delivery arm  202  may be set to a desired angle extending over the center of the pad and a nozzle  224  or end nozzle  226  is disposed at or near the distal end of the delivery arm  202  to deliver rinse agent to the central portion of the pad. In one embodiment, the rinsing agent is delivered at a pressure within a range from about 15 pounds per square inch (psi) to about 100 psi, preferably, from about 30 psi to about 40 psi. In another embodiment, such as when using a hose, the slurry agent is delivered at a pressure within a range from about 1 psi to about 10 psi, preferably, from about 3 psi to about 4 psi. 
       FIG. 3A  depicts the delivery arm  202  having a plurality of nozzles  224  and an end nozzle  226  mounted on the lower surface  222  of the delivery arm  202 . The plurality of nozzles  224  and end nozzle  226  may be used for dispersing the rinse agent and/or slurry to the surface of a substrate or pad. The slurry in the slurry delivery lines  213   a  and  213   b  and the rinse agent in the rinse agent delivery lines  217   a  and  217   b  may be delivered to the nozzles  224  and end nozzles  226  by using delivery channel  306  contained within the DSDA manifolds, as shown in  FIGS. 4A-4B . The manifolds  302  and  304  contain delivery channel  306  along its length which terminates at the adjustable portion  208 . The solenoids  216  and  218  connected to the slurry delivery lines may contain a 2-way valve which allows both the slurry agent and rinse agent to flow through the delivery channel  306  for slurry delivery and for cleaning purposes. A blocking stud  308  may be disposed in one end of the delivery channel  306 . The blocking stud  308  may have different lengths and be used for blocking nozzles depending on the size of the carrier holder. In one embodiment, the delivery channel  306  may be machined channels or may be tubing disposed through and secured in each of the shafts and the arms. In another embodiment, the blocking stud  308  may contain or be made from polyetherethylketone (PEEK). 
     As shown in  FIGS. 3A-3C  and  4 A- 4 B, each manifold  302  and  304  has a plurality of nozzles  224  and end nozzle  226 . The manifolds  302  and  304  are disposed on the lower surface  222  of the delivery arm  202  and are connected to the rinse agent delivery line. In one embodiment, the series of nozzles  224  and end nozzle  226  are attached along the length of the arm. An end nozzle  226 , as shown in  FIGS. 4A-4B , is disposed at an angle relative to the plane of the delivery arm  202 , e.g., an acute angle, to deliver a fluid a distance away from the adjustable portion  208  of the delivery arm  202  towards the central portion of the pad. Each end nozzle  226  is positioned to deliver fluid outwardly beyond the end of the delivery arm  202  to cover the remaining pad regions, including the central portion of the pad, while also overlapping the spray from the adjacent nozzles. Therefore, each region of the pad is exposed to the spray coming from the delivery arm  202 . While in some examples, the spray patterns overlap, in other examples, each spray pattern does not overlap adjacent patterns. In one example, the delivery arm  202  contains two delivery channels  306 , each coupled to and in fluid communication with at least six nozzles  224  and one end nozzle  226 , as depicted in  FIGS. 3A-3C . 
     In another embodiment, the delivery arm  202  may have one, two, or more gas lines mounted on or disposed within the delivery arm  202 . The gas line  219  may be used to flow compressed air or other gases for controlling solenoids, such as valves  212 ,  216 , and  218 . In one example, the gas line  219  is coupled to Y-fitting  251   a , and extends to solenoid  212  and to Y-fitting  251   b . The gas line  219  further extends from Y-fitting  251   b  to solenoids  216  and  218 . 
       FIGS. 5A-5B  depict cross sectional views of a nozzle  502  according to other embodiments. The nozzle  502  may be mounted on the delivery arm  202  at a perpendicular angle relative to a plane extending the length of the delivery arm  202 .  FIG. 5A  depicts the nozzle  502  connected to a slurry delivery line via a tubing where the fluid is being delivered, and is dispensed from the tip  504  of the nozzle  502 . In one embodiment, the tip  504  of the nozzle  502  may be a fine tipped nozzle. In another embodiment, the tip  504  of the nozzle  502  may have an angle α to prevent fluid from clogging the line through the opening of the nozzle  502  as shown in  FIGS. 5A-5B . In another embodiment, the angle α of the tip  504 , relative to the horizontal plane of the delivery arm  202 , may be within a range from about 20° to about 75°, preferably, from about 30° to about 60°, and more preferably, from about 40° to about 50°, for example, about 45°. The nozzle  502  may contain or be made of fluorine-containing polymers, such as perfluoroalkoxy (PFA), fluorinated ethylene propylene (FEP), or polytetrafluoroethylene (PTFE), commercially available as TEFLON® from DuPont. In another example, the tip  504  of the nozzle  502  may be drilled by laser vertically so that the inner surface of the hole is smooth and does not provide rough edges for nucleation of the slurry. 
       FIGS. 6A-6B  illustrate schematic views of hinge assembly  206 , connected to and between the fixed portion  204  and adjustable portion  208  of the delivery arm  202 , as described in several embodiments herein.  FIG. 6A  depicts a schematic view of hinge assembly  206  containing clutch assembly  600  as used in the delivery arm  202 , according to one embodiment.  FIG. 6B  depicts hinge assembly  206  without a clutch assembly, according to another embodiment. 
     The hinge assembly  206  may include a plunger  230 , a stopper  232  and a hinge pin  234 , and uses a locking mechanism to connect the fixed portion  204  of the delivery arm  202  to the adjustable portion  208  of the delivery arm  202 . The locking mechanism on hinge assembly  206  may be a clamp  616 , such as a vice-type clamp, a C-clamp, or a screw clamp. The fixed portion  204  includes a hinged block  602 , which may be fitted with a fixed block  604  connected to the adjustable portion  208 . The hinged block  602  and the fixed block  604  may be secured together by the hinge pin  234 . The hinge pin  234  allows the adjustable portion  208  of the delivery arm  202  to rotate and adjust to the position setting of the adjustable portion  208  according to the size and position of the pad. 
     In one embodiment, degree markings may be engraved onto the outer surface of the hinged block  602 . The hinged block  602  and the fixed block  604  may contain or be made of polypropylene. The hinge pin  234  may contain or be made of polyetherethylketone (PEEK). To lengthen the delivery arm  202  to reach a desired position, spacer block  606  may be positioned between the hinged block  602  and the fixed portion  204 . 
     In another embodiment, the number of spacer blocks  606  may be adjusted according to the length needed to reach the desired position, as depicted in  FIG. 6A . In another example, the spacer block  606  may contain or be made polypropylene. To secure the position setting of the adjustable portion  208 , the plunger  230  may be used to exert pressure onto the hinge pin  234  while securing the position setting of the adjustable portion  208 . The plunger  230  may be placed inside a covered box  608  with one end  610  of the plunger  230  pushing against the hinged block  602 , and the other end  612  of the plunger  230  exposed outside the box. 
     In one example, the plunger  230  may be a spring loaded plunger. The plunger  230  may contain or be made from steel, stainless steel, aluminum, alloys thereof, or other metals. To secure the position setting, the adjustable portion  208  may be set to a position as illustrated by the degree markings, pressure is then applied to the hinge pin  234  by rotating end  612  of the plunger  230  toward the hinge pin  234  and therefore tightening the end  610  of the plunger  230  against the hinge pin  234 . To prevent over-rotation from position setting, a stopper  232  is located on the hinge pin  234  to stop the rotation of the adjustable portion  208 . The hinge assembly  206  may have a locking mechanism or a clamp  616 , such as a vice-type clamp, a C-clamp, or a screw clamp. 
     The delivery arm  202 , the fixed portion  204 , adjustable portion  208  and/or portions thereof may contain or be made of a rigid material, such as polypropylene, which is chemically inert to polishing slurries and solutions. The manifolds  302  and  304 , the nozzles  224 , and end nozzle  226 , as well as, the slurry delivery lines may contain or be made from tubing containing fluorine-containing polymers, such as perfluoroalkoxy (PFA), fluorinated ethylene propylene (FEP), or polytetrafluoroethylene (PTFE), which commercially available as TEFLON® from DuPont, which is not reactive with the various slurries used in the CMP processes. 
       FIG. 7  depicts a multi-pad system  700  representative of the MIRRA® CMP system, available from Applied Materials, Inc. located in Santa Clara, Calif. The multi-pad system  700  has an upper assembly  710  and a lower assembly  712 . Typically, a substrate is positioned or chucked to a carrier head which positions a substrate on the polishing pad and confines the substrate on the pad. The polishing pad  702  is typically rotated and the substrate may also be rotated within the carrier  704 . Additionally, the carrier may be moved radially across the surface of the polishing pad to enhance uniform polishing of the substrate surface. 
     Once the substrate is located in the carrier and the carrier is located over the polishing pad, a solution or slurry is typically delivered to the polishing pad by the delivery arm  202 , as depicted in FIGS.  2  and  3 A- 3 C. The slurry may contain abrasive particles and chemical reagents, such as sodium hydroxide, or may just be deionized water if used on a rinse pad. The carrier is then lowered over the polishing pad so that the substrate contacts the pad and the substrate surface is then polished according to a pre-selected recipe. Towards the end of the polishing step, a rinse agent, such as deionized water, may be delivered to the pad via the nozzles  224  and end nozzles  226  on the adjustable portion to rinse the polishing pad and the substrate. In one example, the rinse agent may be delivered to the polishing pad for a period within a range from about 5 seconds to about 20 seconds. During which time the substrate is raised from the polishing pad  702  and the carrier  704  is moved either to the next processing position in multiple polishing pad systems and/or into position for unloading the substrate and loading the next substrate for processing. Periodically, the rinse agent may also be delivered to the slurry delivery line to rinse out the debris that is still adhered within the slurry delivery line thereby achieving the self-cleaning purpose. 
     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.