Wafer processing tool and method thereof

Abstract

A wafer processing apparatus may include a wafer exchanger including two or more blades, each of the two or more blades may be configured to receive a wafer, the two or more blades may rotate about an axis on a single horizontal plane, and the two or more blades may be configured to receive a wafer. And the two or more blades may be movable between at least the loading cover and a robotic access position; wherein the loading hood may include a wafer station that is vertically movable relative to a blade located in the loading hood, and the wafer station may be configured to remove a wafer from and place a wafer on a blade located in the loading hood. Other devices, loading hoods, and methods are also disclosed herein.

Description

[0001] This application is a divisional application of the Chinese patent application (PCT application number PCT / US2020 / 012957) with an application date of January 9, 2010, application number 202080001514.2, and name “Wafer processing tools and methods thereof”. Technical Field

[0002] The present application relates to wafer processing, and more particularly to wafer processing tools and methods thereof. Background Art

[0003] Wafer processing tools such as chemical mechanical polishing (CMP) systems may experience delays caused by wafer transfers between different processing stations. For example, a process may be delayed because a robot waits to access the wafer before and / or after different processes. Summary of the invention

[0004] In a first aspect, a wafer processing apparatus is provided. The wafer processing apparatus may include: a wafer exchanger including two or more blades, each of the two or more blades configured to receive a wafer, the two or more blades rotatable about an axis in a single horizontal plane, and the two or more blades movable between at least a loading hood and a robot access position; wherein the loading hood includes a wafer station, the wafer station movable vertically relative to the blade located in the loading hood, and the wafer station configured to remove a wafer from and place a wafer on the blade located in the loading hood.

[0005] In a second aspect, a loading hood is provided. The loading hood may include: a wafer station configured to receive a wafer, the wafer station being movable in a vertical direction between a first position where the wafer station is spaced apart from the wafer and a second position where the wafer station receives the wafer; and a recess in the wafer station, the recess being sized to receive a portion of a blade configured to support the wafer when the wafer station moves between the first position and the second position.

[0006] In a third aspect, a method of moving a substrate is provided. The method may include providing a wafer exchanger, the wafer exchanger including two or more blades, each of the two or more blades being configured to receive a wafer, the two or more blades being rotatable about an axis in a single horizontal plane, and the two or more blades being movable between at least a loading hood and a robot access position; placing a first wafer onto the blades of the wafer exchanger at the robot access position; placing a second wafer from a head onto the blades of the wafer exchanger at the loading hood; rotating the wafer exchanger to a position where the second wafer is at the robot access position; removing the second wafer from the wafer exchanger; rotating the wafer exchanger to a position where the first wafer is in the loading hood; placing the first wafer into the head; and placing a third wafer from the robot access position onto the blades of the wafer exchanger.

[0007] Numerous other aspects are provided according to these and other embodiments of the present disclosure. Other features and aspects of the embodiments of the present disclosure will become more apparent from the following detailed description, the appended claims and the accompanying drawings. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] The accompanying drawings described below are for illustrative purposes only and are not necessarily drawn to scale. The accompanying drawings are not intended to limit the scope of the present disclosure in any way. Wherever possible, the same or similar reference numerals will be used throughout the drawings to indicate the same or similar parts.

[0009] Figure 1 A top plan view of a chemical mechanical polishing (CMP) system according to embodiments disclosed herein is shown.

[0010] Figure 2 An enlarged top plan view of a wafer exchanger for use in a CMP system according to embodiments disclosed herein is shown.

[0011] Figure 3 A top plan view of a loading hood and a blade of a wafer exchanger located within the loading hood according to embodiments disclosed herein is shown.

[0012] Figure 4A A stowage cover is shown in a retracted position according to embodiments disclosed herein.

[0013] Figure 4B A stowage cover is shown in an extended position according to embodiments disclosed herein.

[0014] Figure 5A-5D The operation of a wafer exchanger in conjunction with other components of a CMP system according to embodiments described herein is shown.

[0015] Figure 6A top plan view of a CMP system including one or more rinse stations according to embodiments disclosed herein is shown.

[0016] Figure 7 It is shown that according to the embodiments disclosed herein, a Figure 6 A top plan view of a sprayer in a rinse station in a CMP system. DETAILED DESCRIPTION

[0017] Wafer processing equipment such as chemical mechanical polishing (CMP) systems may experience delays caused by the transfer of wafers between different processing stations. For example, before and / or after different processing, the processing may have to wait for a robot to gain access to the wafer, which may be time consuming. Figure 1-Figure 7 The wafer processing apparatus shown in FIG. 1 reduces wafer processing time compared to conventional wafer processing apparatuses.

[0018] refer to Figure 1 , which shows a top plan view of a chemical mechanical polishing (CMP) system 100. Figure 1 1 and described herein, but the concepts disclosed herein may be applied to other wafer processing devices. The CMP system 100 may include a polishing portion 102 and a cleaning and drying portion 104, which process (e.g., clean and / or polish) a wafer 108 (some of which are labeled). The CMP system 100 may include other portions that perform other processes on the wafer. As used herein, a wafer may include an article for manufacturing an electronic device or circuit component. A wafer may also include a semiconductor wafer, a silicon-containing wafer, a patterned or unpatterned wafer, a glass plate, a mask, etc. A through portion 110 may be located between the polishing portion 102 and the cleaning and drying portion 104. The through portion 110 may be an opening between the polishing portion 102 and the cleaning and drying portion 104 to accommodate the transfer of the wafer 108.

[0019] The polishing section 102 may include one or more polishing stations 114. Figure 1 In the illustrated embodiment, the polishing section 102 includes four polishing stations 114, each referred to as a polishing station 114A-114D. The polishing section 102 may include less than or more than four polishing stations 114. Each polishing station 114 may include a polishing pad. The polishing pads are each referred to as polishing pads 116A-116D. The polishing pads 116A-116D may be rotated against the surface of the wafer 108 to perform various polishing processes. One or more slurries (not shown) may be applied between the substrate and the polishing pad to process the substrate. For example, the slurry may remove a specific thickness or layer of the substrate. In some embodiments, the slurry may include corrosion inhibitors and other chemicals that may process the wafer 108.

[0020] The polishing section 102 may include a plurality of heads that hold the wafer 108 against the polishing pads 116A-116D during polishing. For example, each polishing station 114 may include a head. Figure 1 In the embodiment of FIG. 1 , the polishing station 114 includes four heads, each referred to as head 120A- 120D, wherein each individual polishing station 114 may include or be associated with a single head.

[0021] The heads 120A-120D may hold the wafer 108 therein as the heads 120A-120D are transferred to and from the polishing station 114. For example, the heads 120A-120D may hold the wafer 108 therein as the heads are transferred between the loading hood 124 and the polishing station 114. Figure 1 The depicted polishing section 102 includes two loading hoods 124, each referred to as a first loading hood 124A and a second loading hood 124B. The loading hoods 124 can transfer wafers 108 between the heads 120A-120D and the wafer exchanger 130. In some embodiments, the polishing section 102 can include a single loading hood or more than two loading hoods.

[0022] Figure 1 The illustrated CMP system 100 includes two wafer exchangers 130, each referred to as a first wafer exchanger 130A and a second wafer exchanger 130B. In some embodiments, the CMP system 100 may include one or more than two wafer exchangers 130. The first wafer exchanger 130A may rotate in a first direction 132A, and the second wafer exchanger 130B may rotate in a second direction 132B, which may be opposite to the first direction 132A. In some embodiments, the first wafer exchanger 130A and the second wafer exchanger 130B may rotate in the same direction.

[0023] The cleaning and drying section 104 may include a robot 136 (such as a wet robot) that can transfer wafers 108 through the through-portion 110. For example, the robot 136 can load and remove wafers 108 from the first wafer exchanger 130A and / or the second wafer exchanger 130B at the first robot access location 172A and the second robot access location 172B. The robot 136 can also transfer wafers 108 between various stations (not shown) in the cleaning and drying section 104 and the wafer exchanger 130. The robot 136 can access wafers 108 from the wafer exchanger 130 at other robot access locations.

[0024] Reference now Figure 2, which shows an enlarged top plan view of the first wafer exchanger 130A. The first wafer exchanger 130A can be substantially similar or identical to the second wafer exchanger 130B. The first wafer exchanger 130A can include a plurality of blades 234. For example, the first wafer exchanger 130A can include three or more blades 234. Fewer blades, such as two or more blades, can also be used. Figure 1 and Figure 2 In the embodiment of FIG. 1 , the first wafer exchanger 130A includes three blades 234, which are respectively referred to as a first blade 234A, a second blade 234B, and a third blade 234C. Figure 2 In the view of FIG. 2 , the third blade 234C is partially obscured by the wafer 208 received thereon. The blades 234 may be oriented to provide uniform spacing between the blades 234. For example, Figure 2 The three blades 234 may be oriented to be spaced 120° apart relative to the rotation point 236. The first wafer exchanger 130A may rotate about an axis (e.g., an axis extending vertically) centered at the rotation point 236. Other embodiments of the first wafer exchanger 130A may include a different number of blades 234 that may be spaced apart at different angles.

[0025] The blades 234 may be coupled to a support member 238 that may include a rotation point 236. The blades 234 may be, but need not be, substantially similar or identical to one another. The following description refers to the first blade 234A, which may represent the wafer exchanger 130 ( Figure 1 ) of all blades 234 in the first loading cover 124A. The first blade 234A may include an arm 240 that may be attached to the support member 238. As described in more detail below, the arm 240 may be sized to be received in a portion of the first loading cover 124A (e.g., Figure 3 -recess 352A). Arm 240 can be connected to first frame member 242A and second frame member 242B, both of which can be connected to third frame member 242C. In some embodiments, frame members 242A-242C and arm 240 can be integrally formed. Frame members 242A-242C can define the boundaries of opening 244 in first blade 234A. As described in more detail below, opening 244 can be sized and / or configured to allow for the passage of air from a sprayer (e.g., Figure 3 -Spray emitted by the sprayer 356) can pass through the opening 244. The blades 234 can have other configurations.

[0026] The blades 234 may include supports 246 (some are labeled) that support a substrate positioned on the blades 234. Referring to the third blade 234C, the wafer 208 is shown supported by the supports 246. The supports 246 may prevent the surface of the wafer 208 from contacting the frame members 242A-242C of the third blade 234C, which may cause damage to the wafer 208.

[0027] Reference now Figure 3 , which shows a top plan view of the first loading cover 124A and the third blade 234C located in the first loading cover 124A. The first loading cover 124A can be, but need not be, connected to the second loading cover 124B ( Figure 1 ) are substantially similar or identical. The first loading cover 124A may include a wafer station 350 having an annular shape. In some embodiments, the wafer station 350 may have other shapes. The wafer station 350 may be vertically movable to place a wafer onto the third blade 234C and remove a wafer from the third blade 234C. For example, when the wafer station 350 moves vertically relative to the third blade 234C, the third blade 234C may remain fixed in the vertical direction.

[0028] The wafer station 350 may include a notch 352A in which the arm 240 of the third blade 234C is received when the wafer station 350 moves in a vertical direction. The wafer station 350 may also include a notch 352B and a notch 352C that may receive the third frame member 242C of the third blade 234C when the wafer station 350 moves in a vertical direction. The wafer may rest on a raised feature on the wafer station. When the wafer station 350 moves in an upward direction and removes the wafer from the third blade 234C, the wafer is positioned within the plurality of pins 354 (e.g., such that a pocket may be created to center the wafer).

[0029] The first loading cover 124A may further include a sprayer 356, wherein the sprayer 356 may spray a fluid (eg, deionized water) onto the third blade 234C, the substrate (eg, Figure 3) and / or on a head located above the first loading hood 124A. The sprayer 356 may include a first nozzle 358A (marked by a horizontal line) that can rinse the wafer contained on the third blade 234C. The sprayer 356 may include ten to eighteen first nozzles 358A. In some embodiments, the sprayer 356 may include thirteen to fifteen first nozzles 358A that can provide 1.5 liters per minute (lpm) to 2.1 lpm of rinsing solution. In some embodiments, the sprayer 356 may include a second nozzle 358B (marked by a vertical line) that can rinse the membrane. The sprayer 356 may include five to nine second nozzles 358B that can provide 4.0 lpm to 6.0 lpm of rinsing solution. The sprayer 356 may include a third nozzle 358C (marked by a diagonal line) that can rinse a portion of the head, such as at the head (e.g., Figure 4A -head 120D) and wafer (e.g., Figure 4A -wafer 208). The sprayer 356 may include two to four third nozzles 358C that may provide approximately 2.0 lpm to 4.0 lpm of rinsing solution. In some embodiments, the sprayer 356 may include a fourth nozzle 358D (marked by cross lines) that may rinse a retaining ring (not shown) in the head. The sprayer may include two to four fourth nozzles 358D that may provide 1.0 lpm to 4.0 lpm of rinsing solution. The sprayer 356 may include other numbers and configurations of nozzles and / or other flow rates of rinsing solution.

[0030] The nozzles 358A-358D may be independently controlled. For example, the first nozzle 358A may be controlled independently of the second nozzle 358B. Figure 3 As shown, the configuration of the third blade 234C and the configuration of the nozzles 358A-358D are such that the third blade 234C does not block any of the nozzles 358A-358D. For example, the configuration of the frame members 242A-242C and the opening 244 does not block any of the nozzles 358A-358D. This configuration of the frame members 242A-242C and the nozzles 358A-358C can make the heads 120A-120D ( Figure 1 ) can be rinsed without being blocked by a blade (e.g., third blade 234C). In some embodiments, sprayer 356 remains stationary within first loading hood 124A. Thus, sprayer 356 can be coupled to a supply of rinsing solution (not shown) via a fixed tube rather than a flexible tube. Fixed tubes can have reduced maintenance compared to flexible tubes.

[0031] The wafer station 350 may include other features to accommodate the first blade 234A and / or the sprayer 356. For example, the sprayer 356 may have a tab that supports the fourth nozzle 358D. The wafer station 350 may have corresponding notches 359A-359C that accommodate the tab. Thus, the wafer station 350 can move relative to the sprayer 356 without being blocked by the tab.

[0032] Reference now Figure 4A , which shows an example of a head 120D located near a first loading hood 124A. The first loading hood 124A may include or be attached to a support plate 460. The first wafer exchanger 130A may be coupled to the support plate 460 via a shaft 462. A motor 464, such as a servo motor, may be provided in the first direction 132A ( Figure 1 ) or in the second direction 132B ( Figure 1 ) on the rotating shaft 462. Rotation of the shaft 462 causes the first wafer exchanger 130A to rotate about an axis extending through the shaft 462 and / or the rotation point 236.

[0033] The sprayer 356 can be coupled to the support plate 460 via one or more support members 466. In some embodiments, the support members 466 can hold the sprayer 356 in a fixed position relative to the support plate 460. Fluid lines (not shown) can be coupled to the sprayer 356. For example, four fluid lines can be coupled to the sprayer 356, one fluid line for each different type of nozzle 358A-358D.

[0034] The wafer station 350 can be movable in a vertical direction relative to the support plate 460. For example, the wafer station 350 can be movable in a downward or Z-direction and upward in a Z+ direction relative to the support plate 460. The wafer station 350 can be in a first position when the wafer station 350 is spaced apart from the wafer 208 supported on the third blade 234C. The wafer station 350 can be in a second position when the wafer station 350 is located proximate to the head 120D. The support member 468 can couple the wafer station 350 to an actuator 470 that provides vertical movement of the wafer station 350 relative to the support plate 460.

[0035] Figure 4A The first loading cover 124A is shown in a retracted position in which the wafer station 350 is moved in the Z-direction so that the third blade 234C of the first wafer exchanger 130A can be moved into and out of the first loading cover 124A without hindrance. For example, the wafer 208 is supported on the support 246 of the third blade 234C, and the wafer station 350 is located below and spaced apart from the third blade 234C.

[0036] Referring now to FIG. 4B , the first loading cover 124A is shown in an extended position. For example, the wafer support 350 has been moved upward in the Z+ direction to the second position in order to remove the wafer 208 from the third blade 234C or to move the wafer 208 near the head 120D. Figure 4B In the position of the wafer station 350 shown, the wafer 208 rests on raised features of the wafer station 350. Other actions may occur to transfer the wafer 208 to the head 120D.

[0037] In use, the actuator 470 can lower the wafer station 350 by moving the wafer station 350 in the Z-direction to a first position in which the blade can enter the first loading cover 124A without obstruction. The motor 464 can then rotate the shaft 462, which rotates the first wafer exchanger 130A. When a blade such as the third blade 234C (with the wafer 208 located above the blade) is received into the first loading cover 124A, the rotation of the first wafer exchanger 130A can be stopped. The head 120D can be moved to a position above the first loading cover 124A. The actuator 470 can then move the wafer station 350 upward in the Z+ direction to a second position in which the wafer 208 is near the head 120D. The head 120D can grab the wafer 208 and move the wafer 208 to the polishing station 114 ( Figure 1 ) in one or more of the polishing stations 114, a polishing process may be applied to the wafer 208.

[0038] When wafer processing is complete, the head 120D may return to a position above the first loading hood 124A along with the wafer 208. The actuator 470 may move the wafer station 350 in the Z+ direction to a first position in which the wafer station 350 may receive the wafer 208 onto a raised feature of the wafer station 350. The actuator 470 may then lower the wafer station 350 in the Z- direction to a position where the wafer 208 is transferred to the support 246 of the third blade 234C. The actuator 470 may continue to lower the wafer station 350 in the Z- direction to a position where the third blade 234C may be moved unimpeded from the first loading hood 124A.

[0039] In some embodiments, a sensor (not shown) may be located in the first loading hood 124A and may sense the presence of the wafer 208. The sensor may also detect the presence of the wafer 208 in the head 120D. During loading of the wafer 208 into the head 124D, the sensor may determine that no wafer is located on the wafer station 350. The wafer station 350 may then rise in the Z+ direction toward the wafer 208. When the wafer 208 is transferred to the wafer station 350, the sensor may detect the presence of the wafer 208 on the wafer station 350. The wafer station 350 may then continue to rise in the Z+ direction to the head 120D, where the sensor in the head 120D detects the presence of the wafer 208. The wafer 208 may then be loaded into the head 120D. During unloading from the head 120D, the sensor may detect that the wafer 208 has been unloaded from the head 120D and is present on the wafer station 350. The sensor on the wafer station 350 may also detect the absence of the wafer 208 when the wafer 208 is transferred to the third blade 234C. The chemical mechanical polishing (CMP) system 100 may include other sensors.

[0040] During the above-described processes, the sprayer 356 may rinse portions of the first blade 234A, the head 120D, the wafer station 350, and / or the wafer 208. For example, the first nozzle 358A may rinse the wafer 208 after the wafer 208 has been polished. In some embodiments, the wafer 208 may be rinsed while the wafer 208 is in the head 120D and before the wafer 208 is transferred to the wafer station 350. In some embodiments, the wafer 208 may be rinsed while the wafer 208 is in the first loading hood 124A. In some embodiments, the first wafer exchanger 130A may rotate an empty blade into the first loading hood 124A. The lack of substrates in the first loading hood 124A may allow the sprayer 356 to rinse various portions of the head.

[0041] Reference now Figure 5A-5D , which depicts the operation of the first wafer exchanger 130A and the second wafer exchanger 130B in conjunction with other components of the CMP system 100. Wafers with cross-hatching have been polished or processed by the polishing station 114 or other components and are to be transferred to the robot 136. Wafers with diagonal hatching have been received from the robot 136 and are to be transferred to the polishing station 114. Open circles represent blades in the first wafer exchanger 130A and the second wafer exchanger 130B without wafers on the blades.

[0042] Figure 5A-5D The processing shown in Figure 5A ,exist Figure 5AThe first blade (indicated by reference numeral 1) is empty. The second blade (indicated by reference numeral 2) contains substrates that have been processed by the individual polishing stations 114 and returned to the first loading hood 124A and the second loading hood 124B. The third blade (indicated by reference numeral 3) contains substrates that have been received from the robot 136. Figure 5A During the phase depicted, the head ( Figure 5A The substrate is unloaded into the first loading cover 124A and the second loading cover 124B and unloaded onto the second blade. In addition, a new wafer is loaded from the robot 136 onto the third blade.

[0043] The first wafer exchanger 130A can rotate in a first direction 132A, and the second wafer exchanger 130B can rotate in a second direction 132B to achieve Figure 5B The configuration shown. The first blade, which may be empty, may be accommodated in the first loading cover 124A and the second loading cover 124B. The sprayer 356 ( Figure 3 ) can rinse the head located above the first loading cover 124A and the second loading cover 124B without being hindered by the wafer located between the head and the sprayer. Empty blades can also be rinsed. Figure 5B In the configuration shown, the robot 136 may unload processed wafers from the second blade.

[0044] The first wafer exchanger 130A can rotate in a first direction 132A, and the second wafer exchanger 130B can rotate in a second direction 132B to achieve Figure 5C The configuration shown. The robot 136 can load the wafer onto the first blade. In addition, the wafer exchanger 130 can unload the wafer from the third blade to the head, and the head can transfer the wafer to the polishing station 114. Figure 5D The return of the wafer from the polishing station 114 to the loading hood 124 is shown. The first wafer exchanger 130A can rotate in a first direction 132A and the second wafer exchanger 130B can rotate in a second direction 132B to reach Figure 5A The configuration shown is one in which the process is repeated.

[0045] Figure 5A-5D The illustrated process achieves faster processing times relative to conventional CMP systems and methods. For example, the wafer exchanger 130 moves the wafer and blade to a robot access position for the robot 136 (e.g., Figure 1- robot access positions 172A and 172B), so the robot 136 can have more time to unload and load wafers 108. The wafer exchanger 130 allows for faster cycle times by enabling parallel processing of wafers 108. For example, a wafer 108 that has completed polishing can be unloaded, and in parallel, a new wafer 108 can be loaded into the wafer exchanger 130. Thus, the process frees the robot 136 from the bottleneck of wafer movement.

[0046] Wafer Station 350( Figure 3 ) enables the wafer exchanger 130 to move only in a single horizontal plane. Therefore, no vertical movement of the wafer exchanger 130 is performed, which may be time-consuming. Figure 5A-5D As shown, the wafer exchanger 130 can be operated with an empty blade, which allows the head to be flushed by the sprayer 356 when the empty blade is located in the loading hood 124. Multiple blades of the wafer exchanger 130 can be flushed simultaneously. Figure 5A-5D In the depicted embodiment, every third blade entering the loading hood 124 is empty, which enables the head to be rinsed after two wafers have been processed.

[0047] refer to Figure 6 , which illustrates a top plan view of another embodiment of a CMP system, some embodiments of the CMP system 100 may include one or more rinse stations accessible by the wafer exchanger 130. Figure 6 The embodiment of the CMP system 100 includes a first rinse station 670A and a second rinse station 670B, the first rinse station 670A is accessible by the first wafer exchanger 130A, and the second rinse station 670B is accessible by the second wafer exchanger 130B. Figure 6 In the embodiment of FIG. 1 , the wafer 108 on the wafer exchanger 130 may be located at a position including the rinse station 670A or 670B and the loading hood 124. Figure 6 In an embodiment of the present invention, the rinse stations 670A, 670B may be located at the same location as the robot access locations 172A, 172B where the robot 136 may access the wafer 108.

[0048] Reference now Figure 7 , which shows a top plan view of a first rinse station 670A, which can be (although they need not be) the same as or substantially similar to the second rinse station 670B. The first rinse station 670A can include a basin 772 that can collect cleaning fluid that would otherwise be over-sprayed onto the polishing portion 102 ( Figure 1 ). The first rinse station 670A may include a sprayer 774 located within the basin 772. The sprayer 774 may be similar to the sprayer 356 ( Figure 3), but may only include nozzle 776, which is configured to rinse the substrate located at the first rinsing station 670A ( Figure 7 The nozzle 776 may be arranged so that it is not obstructed by the blades of the first wafer exchanger 130A located at the first rinse station 670A. In some embodiments, the layout and / or configuration of the nozzle 776 may be similar to the first nozzle 358A ( Figure 3 ) are the same or substantially similar in layout and / or configuration. For example, the sprayer 774 may include ten to eighteen nozzles 776 that provide 1.0 lpm to 4.0 lpm of flushing fluid. Figure 6 , the wafer 108 can be rinsed by the first rinse station 670A and the second rinse station 670B. The first rinse station 670A and the second rinse station 670B can include other features (not shown) for cleaning the wafer. The first rinse station 670A and the second rinse station 670B can be used to keep the wafer wet, especially after polishing.

[0049] In some embodiments, the wafer 108 can rest on and / or between supports 246 so that the wafer 108 can be moved without clamping the wafer 108. In some embodiments, the nozzles 358A, 358B, 358C, and / or 358D can emit different spray patterns. In some embodiments, one or more hard stops (not shown) can be used to limit the vertical movement of the wafer station 350 (e.g., to limit how low or how high the wafer station 350 can travel during a wafer exchange operation). Any suitable mechanism can be used to move the heads 120A-120D between the polishing station 114 and the loading hood 124.

[0050] The foregoing description discloses only example embodiments. Modifications of the above disclosed apparatus and methods that fall within the scope of the present disclosure will be apparent to those of ordinary skill in the art.

Claims

1. A chemical mechanical polishing system, comprising: Polishing station; at least one loading hood; a wafer exchanger, the wafer exchanger comprising a plurality of blades; a head for holding a wafer against a polishing pad during polishing and for transferring the wafer between the at least one loading hood and the polishing station; A loading hood comprising a wafer station configured to receive a wafer, the wafer station being movable in a vertical direction between a first position in which the wafer station is spaced apart from the wafer and a second position in which the wafer is received by the wafer station, and wherein the wafer station comprises a recess sized to receive a portion of a blade configured to support the wafer as the wafer station moves between the first position and the second position.

2. The system of claim 1, wherein the wafer station has a ring shape.

3. The system of claim 1, further comprising a sprayer positioned in the loading hood, the sprayer comprising one or more nozzles configured to spray at least one fluid.

4. The system of claim 3, wherein the sprayer remains in a fixed position within the loading hood during movement of the wafer station.

5. The system of claim 3, wherein the sprayer includes a tab that supports a nozzle and the wafer station has a corresponding recess that accommodates the tab.

6. The system of claim 1, wherein the arms of the blade are sized to be received in recesses of the first loading shield.

7. The system of claim 1, wherein the wafer station includes two recesses for receiving a frame member of the blade when the wafer station moves in the vertical direction.

8. The system of claim 1 wherein the wafer station includes raised features on which the wafer can rest.

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