JP2017187311A - Leakage inspection device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a leakage inspection device with which it is possible to reduce the occurrence of a fault that leakage occurs in a pressure chamber of a top ring body after the top ring body is assembled to a polishing device.SOLUTION: A leakage inspection device 50 comprises: an attachment unit 500 to which a top ring body 202 is attached; a connection piping 510 connected to flow channels 211 to 214 to pressure chambers 205 to 208 of the top ring body 202 in a state that the top ring body 202 is attached to the attachment unit 500; a fluid supply unit 51 for supplying fluid to the pressure chambers 205 to 208 via the connection piping 510; and a leakage determination unit 54 for determining whether or not there is occurrence of leakage in the pressure chambers 205 to 208 on the basis of a change of pressure and a change of flow rate when fluid is being supplied to the pressure chambers 205 to 208.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a leak inspection apparatus for a top ring of a polishing apparatus, and more particularly to a technique for inspecting whether a leak has occurred in a pressure chamber of a top ring body.

  In recent years, as semiconductor devices are highly integrated, circuit wiring is becoming finer and the distance between wirings is becoming narrower. In the manufacture of semiconductor devices, many types of materials are repeatedly formed in a film shape on a silicon wafer to form a laminated structure. In order to form this laminated structure, a technique for flattening the surface of the wafer is important. As one means for flattening the surface of such a wafer, a polishing apparatus (also referred to as a chemical mechanical polishing apparatus) that performs chemical mechanical polishing (CMP) is widely used.

  The thickness of the thin film formed on the surface of the semiconductor wafer varies depending on the position in the radial direction of the semiconductor wafer, depending on the characteristics of the film forming method and apparatus. That is, it has a film thickness distribution in the radial direction. For this reason, in a polishing apparatus that uniformly presses and polishes the entire surface of the semiconductor wafer, polishing is performed uniformly over the entire surface of the semiconductor wafer, so that the same polishing amount distribution as the film thickness distribution on the surface of the semiconductor wafer can be obtained. Can not. Therefore, by applying a partially different pressure to the semiconductor wafer and making the pressing force on the polishing surface of the thick film portion larger than the pressing force on the polishing surface of the thin film portion, A polishing apparatus including a top ring (substrate holding apparatus) that can selectively increase the polishing rate has been proposed. Thereby, it is possible to perform polishing without excess or deficiency over the entire surface of the substrate without depending on the film thickness distribution at the time of film formation.

  However, the pressure of fluid such as pressurized air supplied to a plurality of pressure chambers located on the back side of the semiconductor wafer is controlled, and the pressure applied to the semiconductor wafer is partially controlled to the semiconductor wafer. When pressing at different pressures, the membrane (elastic film) existing at the boundary between different pressures may be damaged or air leakage may occur without maintaining airtightness between the semiconductor wafer and the membrane. Then, each place of the semiconductor wafer cannot be pressed with a predetermined pressing force, which may adversely affect the polishing result.

  Therefore, when the membrane (elastic membrane) is damaged and a leak occurs in the pressure chamber, or when a leak occurs without maintaining airtightness between the substrate and the membrane (elastic membrane), this leak is detected. A polishing apparatus provided with a top ring (substrate holding apparatus) that can be used has been proposed (see, for example, Patent Document 1).

JP 2004-349340 A

  However, in the conventional polishing apparatus, the leak can be detected after the top ring main body is assembled to the polishing apparatus. However, when the occurrence of the leak is detected, the assembled top ring main body (the leak is not defective). There was a problem that it took time and labor to remove a certain top ring body) and reassemble it to a new top ring body. As a result of detecting the leak after the top ring body is assembled to the polishing apparatus again, if the occurrence of the leak is detected again, the assembled top ring body (top ring body having a leak defect) Had to be removed and reassembled on another new top ring body.

  The present invention has been made in view of the above problems, and a leak inspection apparatus capable of reducing the occurrence of a problem in which a leak occurs in the pressure chamber of the top ring body after the top ring body is assembled to the polishing apparatus. The purpose is to provide.

  A leak inspection apparatus according to the present invention includes an attachment unit to which a top ring body is attached, and a connection pipe connected to a flow path to the pressure chamber of the top ring body in a state where the top ring body is attached to the attachment unit. And a fluid supply unit that supplies fluid to the pressure chamber via the connection pipe, and the pressure and the flow rate when the fluid is supplied to the pressure chamber, A leak determination unit that determines whether or not a leak has occurred in the chamber.

  According to this configuration, the top ring body is attached to the mounting unit, the connection pipe is connected to the flow path communicating with the pressure chamber of the top ring body, and the fluid is supplied to the pressure chamber via the connection pipe. Then, based on the change in pressure and the change in flow rate when the fluid is supplied to the pressure chamber, it is determined whether or not a leak has occurred in the pressure chamber. Thereby, before attaching a top ring main body to a grinding | polishing apparatus, it can be checked whether a leak generate | occur | produces in the pressure chamber of a top ring main body. Therefore, it is possible to reduce the occurrence of a problem that a leak occurs in the pressure chamber of the top ring body after the top ring body is assembled to the polishing apparatus.

  In addition, the leak inspection apparatus of the present invention includes a storage unit that stores pressure control data of the fluid when performing a polishing process, and a pressure when supplying the fluid to the pressure chamber based on the pressure control data. A pressure control unit for controlling, and a flow rate measurement unit for measuring a flow rate of the fluid supplied to the pressure chamber in a state where a pressure when the fluid is supplied to the pressure chamber is controlled. Good.

  According to this configuration, whether or not a leak occurs in the pressure chamber by supplying the fluid at the pressure at which the actual polishing process is performed based on the pressure control data and measuring the change in the flow rate of the fluid at that time. You can check that. For example, when the fluid is supplied at a predetermined pressure (a constant pressure) and the flow rate of the fluid changes, it can be determined that a leak has occurred in the pressure chamber. This check can be performed before the top ring body is attached to the polishing apparatus. Thereby, after the top ring body is assembled to the polishing apparatus, it is possible to reduce the occurrence of a problem that a leak occurs in the pressure chamber of the top ring body.

  The leak inspection apparatus of the present invention may further include a warning display processing unit that performs processing for displaying a warning when it is determined by the leak determination unit that a leak has occurred in the pressure chamber.

  According to this configuration, when it is determined that a leak has occurred in the pressure chamber of the top ring body, a warning is displayed, so that the operator can easily recognize whether or not a leak has occurred.

  The leak inspection apparatus of the present invention may further include a graph display processing unit that performs processing for displaying the change in pressure and the change in flow rate when the fluid is supplied to the pressure chamber. .

  According to this configuration, the pressure change and the flow rate change when the fluid is supplied to the pressure chamber of the top ring main body are displayed in a graph, so that the operator can easily check the situation where the leak is occurring. Can do.

  ADVANTAGE OF THE INVENTION According to this invention, after attaching a top ring main body to a grinding | polishing apparatus, it can reduce that the malfunction which a leak generate | occur | produces in the pressure chamber of a top ring main body arises.

It is a top view which shows the whole structure of the substrate processing apparatus in embodiment of this invention. It is the schematic which shows the structure of the grinding | polishing apparatus (1st grinding | polishing unit) in embodiment of this invention. It is a typical sectional view of a substrate holding device (top ring) in an embodiment of the invention. It is a figure which shows the structure of the leak test | inspection apparatus in embodiment of this invention. It is a figure which shows an example of the graph display in embodiment of this invention.

  Hereinafter, a leak inspection apparatus according to an embodiment of the present invention will be described with reference to the drawings. In this embodiment, the case of a leak inspection apparatus used as a leak inspection apparatus for a top ring of a polishing apparatus is illustrated.

  First, the overall configuration of the substrate processing apparatus will be described with reference to FIG. The substrate processing apparatus is a polishing apparatus that polishes a wafer, for example. FIG. 1 is a plan view showing the overall configuration of the substrate processing apparatus in the present embodiment. As shown in FIG. 1, the substrate processing apparatus includes a substantially rectangular housing 1, and the interior of the housing 1 is divided into a load / unload unit 2, a polishing unit 3 and a cleaning unit 4 by partition walls 1a and 1b. It is partitioned. The load / unload unit 2, the polishing unit 3, and the cleaning unit 4 are assembled independently and exhausted independently. The substrate processing apparatus has a control unit 5 that controls the substrate processing operation.

  The load / unload unit 2 includes two or more (four in this embodiment) front load units 20 on which wafer cassettes for stocking a large number of wafers (substrates) are placed. These front load portions 20 are arranged adjacent to the housing 1 and are arranged along the width direction (direction perpendicular to the longitudinal direction) of the substrate processing apparatus. The front load unit 20 can be equipped with an open cassette, a SMIF (Standard Manufacturing Interface) pod, or a FOUP (Front Opening Unified Pod). Here, SMIF and FOUP are sealed containers capable of maintaining an environment independent of the external space by accommodating a wafer cassette inside and covering with a partition wall.

  Further, a traveling mechanism 21 is laid along the front load unit 20 in the load / unload unit 2, and one transport robot that can move along the arrangement direction of the wafer cassettes on the traveling mechanism 21. A (loader) 22 is installed. The transfer robot 22 can access the wafer cassette mounted on the front load unit 20 by moving on the traveling mechanism 21. The transfer robot 22 has two upper and lower hands. The upper hand is used to return the processed wafer to the wafer cassette, and the lower hand is used to remove the unprocessed wafer from the wafer cassette. The upper and lower hands can be used properly. Furthermore, the lower hand of the transfer robot 22 is configured to be able to reverse the wafer by rotating around its axis.

  Since the load / unload unit 2 is an area where it is necessary to maintain the cleanest state, the pressure inside the load / unload unit 2 is higher than any of the outside of the substrate processing apparatus, the polishing unit 3 and the cleaning unit 4. Is always maintained. The polishing unit 3 is the most dirty region because slurry is used as the polishing liquid. Therefore, a negative pressure is formed inside the polishing unit 3, and the pressure is maintained lower than the internal pressure of the cleaning unit 4. The load / unload unit 2 is provided with a filter fan unit (not shown) having a clean air filter such as a HEPA filter, a ULPA filter, or a chemical filter. From the filter fan unit, particles, toxic vapor, Clean air from which toxic gases have been removed is constantly blowing out.

  The polishing unit 3 is a region where the wafer is polished (flattened), and includes a first polishing unit 3A, a second polishing unit 3B, a third polishing unit 3C, and a fourth polishing unit 3D. The first polishing unit 3A, the second polishing unit 3B, the third polishing unit 3C, and the fourth polishing unit 3D are arranged along the longitudinal direction of the substrate processing apparatus as shown in FIG.

  As shown in FIG. 1, the first polishing unit 3A includes a polishing table 30A to which a polishing pad 10 having a polishing surface is attached, and polishing while holding the wafer and pressing the wafer against the polishing pad 10 on the polishing table 30A. A top ring (substrate holding part) 31A for polishing, a polishing liquid supply nozzle 32A for supplying a polishing liquid or a dressing liquid (for example, pure water) to the polishing pad 10, and dressing of the polishing surface of the polishing pad 10 A dresser 33A for the purpose, and an atomizer 34A that sprays a mixed fluid of liquid (for example, pure water) and gas (for example, nitrogen gas) or a liquid (for example, pure water) in the form of a mist onto the polishing surface.

  Similarly, the second polishing unit 3B includes a polishing table 30B to which the polishing pad 10 is attached, a top ring (substrate holding unit) 31B, a polishing liquid supply nozzle 32B, a dresser 33B, and an atomizer 34B. The third polishing unit 3C includes a polishing table 30C to which the polishing pad 10 is attached, a top ring (substrate holding unit) 31C, a polishing liquid supply nozzle 32C, a dresser 33C, and an atomizer 34C. The 4 polishing unit 3D includes a polishing table 30D to which the polishing pad 10 is attached, a top ring (substrate holding unit) 31D, a polishing liquid supply nozzle 32D, a dresser 33D, and an atomizer 34D.

  Next, a transfer mechanism for transferring the wafer will be described. As shown in FIG. 1, a first linear transporter 6 is disposed adjacent to the first polishing unit 3A and the second polishing unit 3B. The first linear transporter 6 has four transfer positions along the direction in which the first polishing unit 3A and the second polishing unit 3B are arranged (first transfer position TP1, second transfer in order from the load / unload unit side). This is a mechanism for transferring the wafer between position TP2, third transfer position TP3, and fourth transfer position TP4.

  Further, the second linear transporter 7 is disposed adjacent to the third polishing unit 3C and the fourth polishing unit 3D. The second linear transporter 7 has three transfer positions along the direction in which the third polishing unit 3C and the fourth polishing unit 3D are arranged (the fifth transfer position TP5 and the sixth transfer in order from the load / unload unit side). This is a mechanism for transferring the wafer between the position TP6 and the seventh transfer position TP7).

  The wafer is transferred to the first polishing unit 3A and the second polishing unit 3B by the first linear transporter 6. As described above, the top ring 31A of the first polishing unit 3A moves between the polishing position and the second transport position TP2 by the swing operation of the top ring head 60. Therefore, the wafer is transferred to the top ring 31A at the second transfer position TP2. Similarly, the top ring 31B of the second polishing unit 3B moves between the polishing position and the third transfer position TP3, and the delivery of the wafer to the top ring 31B is performed at the third transfer position TP3. The top ring 31C of the third polishing unit 3C moves between the polishing position and the sixth transfer position TP6, and the delivery of the wafer to the top ring 31C is performed at the sixth transfer position TP6. The top ring 31D of the fourth polishing unit 3D moves between the polishing position and the seventh transfer position TP7, and the delivery of the wafer to the top ring 31D is performed at the seventh transfer position TP7.

  A lifter 11 for receiving a wafer from the transfer robot 22 is disposed at the first transfer position TP1. The wafer is transferred from the transfer robot 22 to the first linear transporter 6 through the lifter 11. A shutter (not shown) is provided between the lifter 11 and the transfer robot 22 in the partition wall 1a. When the wafer is transferred, the shutter is opened so that the wafer is transferred from the transfer robot 22 to the lifter 11. It has become. A swing transporter 12 is arranged between the first linear transporter 6, the second linear transporter 7, and the cleaning unit 4. The swing transporter 12 has a hand that can move between the fourth transfer position TP4 and the fifth transfer position TP5, and transfers the wafer from the first linear transporter 6 to the second linear transporter 7. Is performed by the swing transporter 12. The wafer is transferred to the third polishing unit 3C and / or the fourth polishing unit 3D by the second linear transporter 7. The wafer polished by the polishing unit 3 is transferred to the cleaning unit 4 via the swing transporter 12.

  Since the first polishing unit 3A, the second polishing unit 3B, the third polishing unit 3C, and the fourth polishing unit 3D have the same configuration, the first polishing unit 3A will be described below.

  FIG. 2 is a schematic diagram showing the configuration of the first polishing unit 3A in the present embodiment. As shown in FIG. 2, the first polishing unit 3A includes a polishing table 30A and a top ring 31A that holds a substrate such as a wafer as a polishing target and presses the polishing table on the polishing table.

  The polishing table 30A is connected to a motor (not shown) arranged below the table shaft 30Aa and is rotatable around the table shaft 30Aa. A polishing pad 10 is affixed to the upper surface of the polishing table 30A, and the polishing surface 10a of the polishing pad 10 constitutes a polishing surface for polishing the wafer W. A polishing liquid supply nozzle 32A is installed above the polishing table 30A. The polishing liquid supply nozzle 102 supplies the polishing liquid Q onto the polishing pad 10 on the polishing table 30A.

  The top ring 31A basically includes a top ring main body 202 that presses the wafer W against the polishing surface 10a, and a retainer ring 203 that holds the outer peripheral edge of the wafer W and prevents the wafer W from jumping out of the top ring. It is configured.

  The top ring 31 </ b> A is connected to a top ring shaft 111, and the top ring shaft 111 moves up and down with respect to the top ring head 110 by a vertical movement mechanism 124. By the vertical movement of the top ring shaft 111, the entire top ring 31A is moved up and down with respect to the top ring head 110 for positioning. A rotary joint 125 is attached to the upper end of the top ring shaft 111.

  The vertical movement mechanism 124 that moves the top ring shaft 111 and the top ring 31 </ b> A up and down includes a bridge 128 that rotatably supports the top ring shaft 111 via a bearing 126, a ball screw 132 attached to the bridge 128, and a support 130. And a servo motor 138 provided on the support table 129. A support base 129 that supports the servo motor 138 is fixed to the top ring head 110 via a support 130.

  The ball screw 132 includes a screw shaft 132a connected to the servo motor 138 and a nut 132b into which the screw shaft 132a is screwed. The top ring shaft 111 moves up and down integrally with the bridge 128. Therefore, when the servo motor 138 is driven, the bridge 128 moves up and down via the ball screw 132, and thereby the top ring shaft 111 and the top ring 31A move up and down.

  The top ring shaft 111 is connected to the rotary cylinder 112 via a key (not shown). The rotating cylinder 112 includes a timing pulley 113 on the outer periphery thereof. A top ring rotation motor 114 is fixed to the top ring head 110, and the timing pulley 113 is connected to a timing pulley 116 provided on the top ring rotation motor 114 via a timing belt 115. Accordingly, when the top ring rotation motor 114 is rotationally driven, the rotary cylinder 112 and the top ring shaft 111 rotate together via the timing pulley 116, the timing belt 115, and the timing pulley 113, and the top ring 31A rotates. The top ring rotary motor 114 includes an encoder 140. The encoder 140 has a function of detecting the rotational angle position of the top ring 31A and a function of integrating the rotational speed of the top ring 31A. Further, a sensor for detecting the rotation angle “reference position (0 degree)” of the top ring 31A may be provided separately. The top ring head 110 is supported by a top ring head shaft 117 that is rotatably supported by a frame (not shown).

  The control unit 5 controls each device in the apparatus including the top ring rotary motor 114, the servo motor 138, and the encoder 140.

  In the first polishing unit 3A configured as shown in FIG. 2, the top ring 31A can hold a substrate such as a wafer W on its lower surface. The top ring head 110 is configured to be pivotable about the top ring head shaft 117, and the top ring 31 </ b> A holding the wafer W on the lower surface of the top ring head 110 rotates from the receiving position of the wafer W by the rotation of the top ring head 110. Moved upwards. Then, the top ring 31 </ b> A is lowered to press the wafer W against the surface (polishing surface) 10 a of the polishing pad 10. At this time, the top ring 31A and the polishing table 30A are respectively rotated, and the polishing liquid is supplied onto the polishing pad 10 from the polishing liquid supply nozzle 32A provided above the polishing table 30A. Thus, the wafer W is brought into sliding contact with the polishing surface 10a of the polishing pad 10 to polish the surface of the wafer W.

  Next, the top ring (substrate holding part) in the polishing apparatus of the present invention will be described. FIG. 3 is a schematic cross-sectional view of a top ring 31A that constitutes a substrate holding device that holds a wafer W that is an object to be polished and presses the wafer W against a polishing surface on a polishing table. In FIG. 3, only main components constituting the top ring 31A are shown.

  As shown in FIG. 3, the top ring 31A includes a top ring body (also referred to as a carrier) 202 that presses the wafer W against the polishing surface 10a of the polishing pad 10, and a retainer ring 203 that directly presses the polishing surface 101a. Basically composed. The top ring body (carrier) 202 is made of a substantially disk-shaped member, and the retainer ring 203 is attached to the outer peripheral portion of the top ring body 202. The top ring body 202 is formed of a resin such as engineering plastic (for example, PEEK). An elastic film (membrane) 204 that is in contact with the back surface of the wafer is attached to the lower surface of the top ring body 202. The elastic membrane (membrane) 204 is formed of a rubber material having excellent strength and durability, such as ethylene propylene rubber (EPDM), polyurethane rubber, and silicon rubber.

  The elastic membrane (membrane) 204 has a plurality of concentric partition walls 204a. By these partition walls 204a, a circular center chamber 205 and an annular ripple chamber are provided between the upper surface of the elastic film 204 and the lower surface of the top ring body 202. 206, an annular outer chamber 207, and an annular edge chamber 208 are formed. That is, a center chamber 205 is formed at the center of the top ring main body 202, and a ripple chamber 206, an outer chamber 207, and an edge chamber 208 are sequentially formed concentrically from the center toward the outer circumferential direction. The elastic membrane (membrane) 204 has a plurality of holes 204h penetrating in the ripple area (ripple chamber 206) in the thickness direction of the elastic membrane for wafer adsorption. In this embodiment, the hole 204h is provided in the ripple area, but it may be provided in a place other than the ripple area.

  In the top ring body 202, a channel 211 communicating with the center chamber 205, a channel 212 communicating with the ripple chamber 206, a channel 213 communicating with the outer chamber 207, and a channel 214 communicating with the edge chamber 208 are formed. Has been. A flow path 211 communicating with the center chamber 205, a flow path 213 communicating with the outer chamber 207, and a flow path 214 communicating with the edge chamber 208 are connected to the flow paths 221, 223, and 224 via the rotary joint 225, respectively. ing. The flow paths 221, 223, and 224 are connected to the pressure adjusting unit 230 via valves V1-1, V3-1, and V4-1 and pressure regulators R1, R3, and R4, respectively. The flow paths 221, 223, and 224 are connected to the vacuum source 231 via valves V1-2, V3-2, and V4-2, respectively, and via valves V1-3, V3-3, and V4-3. Can communicate with the atmosphere. Furthermore, the flow path 222 is connected to the pressure regulator R6 via the steam / water separation tank 235 and the valve V2-1. The pressure regulator R6 is, for example, an electropneumatic regulator. The pressure regulator R6 is connected to the control unit 5 via a control line, and the control unit 5 controls the pressure regulator R6. As described above, the pressure regulator R6 communicates with the ripple chamber 206 via the flow path 222 and the flow path 212, and the pressure of the gas (for example, nitrogen) supplied to the ripple chamber 206 in the membrane 204 of the top ring 31A. Adjust.

  On the other hand, the flow path 212 communicating with the ripple chamber 206 is connected to the flow path 222 via the rotary joint 225. And the flow path 222 is connected to the pressure adjustment part 230 via the steam-water separation tank 235, valve | bulb V2-1, and pressure regulator R2. The flow path 222 is connected to the vacuum source 131 via the steam / water separation tank 235 and the valve V2-2, and can communicate with the atmosphere via the valve V2-3.

  A retainer ring pressurizing chamber 209 made of an elastic film is also formed immediately above the retainer ring 203. The retainer ring pressurizing chamber 209 includes a flow path 215 formed in the top ring body (carrier) 202 and a rotary. It is connected to the flow path 226 through a joint 225. The flow path 226 is connected to the pressure adjusting unit 230 via the valve V5-1 and the pressure regulator R5. The flow path 226 is connected to the vacuum source 231 through the valve V5-2 and can communicate with the atmosphere through the valve V5-3. The pressure regulators R1, R2, R3, R4, and R5 adjust the pressure of the pressure fluid supplied from the pressure adjusting unit 230 to the center chamber 205, the ripple chamber 206, the outer chamber 207, the edge chamber 208, and the retainer ring pressurizing chamber 209, respectively. It has a pressure adjustment function. Pressure regulators R1, R2, R3, R4, R5 and valves V1-1 to V1-3, V2-1 to V2-3, V3-1 to V3-3, V4-1 to V4-3, V5-1 V5-3 is connected to the control part 5 (refer FIG. 1 and 2), and those operation | movements are controlled. Pressure sensors P1, P2, P3, P4 and P5 and flow sensors F1, F2, F3, F4 and F5 are installed in the flow paths 221, 222, 223, 224 and 226, respectively.

  In the top ring 31A configured as shown in FIG. 3, as described above, the center chamber 205 is formed in the central portion of the top ring main body 202, and the ripples are sequentially concentrically from the center toward the outer peripheral direction. The chamber 206, the outer chamber 207, and the edge chamber 208 are formed, and the pressure of the fluid supplied to the center chamber 205, the ripple chamber 206, the outer chamber 207, the edge chamber 208, and the retainer ring pressurizing chamber 209 is adjusted by the pressure adjusting unit 230 and the pressure. Each of the regulators R1, R2, R3, R4, and R5 can be adjusted independently. With such a structure, the pressing force for pressing the wafer W against the polishing pad 10 can be adjusted for each region of the wafer W, and the pressing force for the retainer ring 203 to press the polishing pad 10 can be adjusted.

  Next, a series of polishing processes by the substrate processing apparatus configured as shown in FIGS. 1 to 3 will be described.

  The top ring 31A receives the wafer W from the first linear transporter 6 and holds it by vacuum suction. The elastic membrane (membrane) 204 is provided with a plurality of holes 204 h for vacuum-sucking the wafer W, and these holes 204 h communicate with the vacuum source 131. The top ring 31 </ b> A holding the wafer W by vacuum suction is lowered to a preset top ring setting position during polishing. In this polishing setting position, the retainer ring 203 is in contact with the surface (polishing surface) 10a of the polishing pad 10, but before polishing, the wafer W is attracted and held by the top ring 31A. There is a slight gap (for example, about 1 mm) between the polishing surface) and the surface of the polishing pad 10 (polishing surface) 10a. At this time, both the polishing table 30A and the top ring 31A are rotationally driven. In this state, the elastic film (membrane) 204 on the back side of the wafer is expanded, the lower surface (surface to be polished) of the wafer is brought into contact with the surface (polishing surface) of the polishing pad 10, and the polishing table 30A and the top ring 31A Are moved until the surface (surface to be polished) of the wafer W reaches a predetermined state (for example, a predetermined film thickness).

  After completion of the wafer processing process on the polishing pad 10, the wafer W is attracted to the top ring 31A, the top ring 31A is lifted, and the substrate transfer device (also referred to as a pusher) of the first linear transporter (substrate transport unit) 6 is provided. ) 150, and the wafer W is released (released).

  Next, the configuration of the leak inspection apparatus of the present embodiment will be described with reference to FIG. FIG. 4 is a diagram showing a configuration of the leak inspection apparatus according to the present embodiment. The leak inspection apparatus 50 is an apparatus for checking whether or not a leak occurs in the pressure chamber of the top ring body 202 before assembling the top ring body 202 to the polishing apparatus (for example, the polishing unit 3A). .

  As shown in FIG. 4, the leak inspection apparatus 50 includes a mounting unit 500 that is a jig to which the top ring main body 202 (the top ring main body 202 before being assembled to the polishing apparatus) is mounted, and the top ring main body 202 to the mounting unit 500. Is attached to the center chamber 205, which is the pressure chamber of the top ring body 202, the ripple chamber 206, the outer chamber 207, and the connection pipe 510 connected to the flow paths 211 to 214 to the edge chamber 208.

  Further, the leak inspection apparatus 50 includes a fluid supply unit 51 that supplies a fluid to each pressure chamber (center chamber 205, ripple chamber 206, outer chamber 207, and edge chamber 208) via a connection pipe 510, and each pressure chamber (center). Chamber 205, ripple chamber 206, outer chamber 207, edge chamber 208) and pressure control unit 52 that controls the pressure of the fluid supplied to each chamber, and each pressure chamber (center chamber 205, ripple chamber 206, outer chamber 207, edge chamber 208). Changes in flow rate and flow rate when fluid is supplied to the flow rate measuring unit 53 that measures the flow rate of the fluid supplied to the pressure chambers, and the pressure chambers (center chamber 205, ripple chamber 206, outer chamber 207, and edge chamber 208). On the basis of the change in the pressure, it is determined whether or not a leak has occurred in each pressure chamber (center chamber 205, ripple chamber 206, outer chamber 207, edge chamber 208). And a leakage determination unit 54.

  The leak inspection apparatus 50 includes a storage unit 520 constituted by a memory device or the like, and the storage unit 520 stores fluid pressure control data when the wafer W is actually polished. The pressure control data can be set arbitrarily. The pressure control unit 52 has a function of controlling the pressure when fluid is supplied to each pressure chamber (center chamber 205, ripple chamber 206, outer chamber 207, edge chamber 208) based on the pressure control data. In addition, the flow rate measurement unit 53 controls the pressure when supplying fluid to each pressure chamber (center chamber 205, ripple chamber 206, outer chamber 207, edge chamber 208) based on the pressure control data. It has a function of measuring the flow rate of the fluid supplied to each pressure chamber (center chamber 205, ripple chamber 206, outer chamber 207, edge chamber 208).

  Furthermore, the leak inspection apparatus 50 includes a display unit 530 configured with a display device or the like. The leak inspection device 50 displays when the leak determination unit 54 determines that a leak has occurred in any of the pressure chambers (center chamber 205, ripple chamber 206, outer chamber 207, edge chamber 208). Fluid is supplied to the warning display processing unit 55 that performs processing for displaying a warning on the screen of the unit 530 and the pressure chambers (the center chamber 205, the ripple chamber 206, the outer chamber 207, and the edge chamber 208). The graph display processing unit 56 performs processing for displaying the change in pressure and the change in flow rate on the screen of the display unit 530.

  FIG. 5 is a diagram illustrating an example of a graph display in the present embodiment. As shown in FIG. 5, on the screen of the display unit 530, for example, for each pressure chamber (for example, the center chamber 205), a flow rate change graph with time on the horizontal axis and flow rate on the vertical axis, and time on the horizontal axis. A pressure change graph with the vertical axis as pressure is displayed. In the example of FIG. 5, the supply of fluid to the pressure chamber (for example, the center chamber 205) is started at time t0. Therefore, at time t0, the flow rate of the fluid supplied to the pressure chamber (for example, the center chamber 205) temporarily increases, and when the fluid fills the inside of the pressure chamber (for example, the center chamber 205), the flow rate decreases to near zero. To do. On the other hand, the pressure increases immediately after the fluid supply to the pressure chamber (for example, the center chamber 205) is started. After that, when the fluid is filled in the pressure chamber (for example, the center chamber 205), the constant pressure is increased. Kept.

  In FIG. 5, the flow rate of the fluid supplied to the pressure chamber (for example, the center chamber 205) starts to increase again from around time t1, and then the fluid continues to flow at a constant flow rate. When there is such an increase in flow rate, the leak determination unit 54 determines that a leak has occurred in the pressure chamber (for example, the center chamber 205). Even when a leak is occurring, the pressure is controlled so as to be kept constant, so that no change in pressure is observed around time t1.

  Note that such pressure change graph and flow rate change graph data can be stored in the storage unit 520 with the identification number of the top ring body 202. Further, data of a pressure change graph and a flow rate change graph previously stored in the storage unit 520 can be read and compared with a pressure change graph and a flow rate change graph obtained by inspection. The storage unit 520 may store a reference waveform pattern of a normal waveform (a waveform pattern without leakage) and an abnormal waveform (a waveform pattern with leakage) of a pressure change graph or a flow rate change graph. The determination unit 54 can also determine whether or not a leak has occurred by comparing the pressure change graph and the flow rate change graph obtained by the inspection with a reference waveform model (pattern matching).

  Next, the operation of the leak inspection apparatus 50 configured as described above will be described. When performing a leak check of the top ring main body 202 (the top ring main body 202 before being assembled to the polishing apparatus) using the leak inspection apparatus 50 of the present embodiment, first, the top ring main body 202 is attached to the attachment unit 500. The connection pipe 510 is connected to the flow paths 211 to 214 to the pressure chambers (the center chamber 205, the ripple chamber 206, the outer chamber 207, and the edge chamber 208) of the top ring body 202.

  Thereafter, based on the pressure control data, the pressure when supplying fluid to each pressure chamber (center chamber 205, ripple chamber 206, outer chamber 207, edge chamber 208) is controlled, and each pressure chamber (center chamber 205, It is determined whether or not a leak has occurred in the ripple chamber 206, the outer chamber 207, and the edge chamber 208). In this case, a fluid is supplied to each pressure chamber (center chamber 205, ripple chamber 206, outer chamber 207, edge chamber 208) at the pressure at which the wafer W is actually polished based on the pressure control data. Whether or not a leak occurs in each of the pressure chambers 205 to 208 by measuring a change in the flow rate of the fluid supplied to each of the pressure chambers (the center chamber 205, the ripple chamber 206, the outer chamber 207, and the edge chamber 208). Determine. The flow rate is measured in a state where the pressure is stable.

  According to such a leak inspection apparatus 50 of the present embodiment, the top ring main body 202 is attached to the attachment unit 500 and connected to the flow paths 211 to 214 communicating with the pressure chambers 205 to 208 of the top ring main body 202. 510 is connected to supply fluid to each of the pressure chambers 205 to 208 via the connection pipe 510. And based on the change of the pressure when supplying the fluid to each pressure chamber 205-208, and the change of flow volume, it is determined whether the leak has generate | occur | produced in each pressure chamber 205-208. Thereby, before attaching the top ring main body 202 to a grinding | polishing apparatus (polishing unit 3A), it can be checked whether a leak generate | occur | produces in each pressure chamber 205-208 of the top ring main body 202. FIG. Therefore, after the top ring main body 202 is assembled to the polishing apparatus (polishing unit 3A), it is possible to reduce the occurrence of a problem that a leak occurs in the pressure chambers 205 to 208 of the top ring main body 202.

  Further, in the present embodiment, each pressure chamber 205 is measured by supplying a fluid at a pressure when actually polishing the wafer W based on the pressure control data, and measuring a change in the flow rate of the fluid at that time. It is possible to check whether or not a leak occurs at ~ 208. For example, when the fluid is supplied at a predetermined pressure (a constant pressure) and there is a change in the flow rate of the fluid, it is determined that a leak has occurred in each of the pressure chambers 205 to 208. Can do. This check can be performed before the top ring main body 202 is attached to the polishing apparatus (polishing unit 3A). Thereby, after assembling the top ring main body 202 to the polishing apparatus (polishing unit 3 </ b> A), it is possible to reduce the occurrence of a problem that a leak occurs in each of the pressure chambers 205 to 208 of the top ring main body 202.

  In the present embodiment, if it is determined that a leak has occurred in any of the pressure chambers 205 to 208 of the top ring main body 202, a warning is displayed on the screen of the display unit 530, etc. Can easily recognize whether or not a leak has occurred.

  In the present embodiment, the pressure change and the flow rate change when the fluid is supplied to the pressure chambers 205 to 208 of the top ring main body 202 are displayed in a graph on the screen of the display unit 530. It is possible to easily check the situation where the occurrence of the error occurs.

  The embodiments of the present invention have been described above by way of example, but the scope of the present invention is not limited to these embodiments, and can be changed or modified according to the purpose within the scope of the claims. is there.

  As described above, the leak inspection apparatus according to the present invention has an effect that it is possible to reduce the occurrence of a problem that a leak occurs in the pressure chamber of the top ring body after the top ring body is assembled to the polishing apparatus. In addition, it is useful as a leak inspection apparatus for a top ring of a polishing apparatus.

DESCRIPTION OF SYMBOLS 50 Leak inspection apparatus 51 Fluid supply part 52 Pressure control part 53 Flow rate measurement part 54 Leak determination part 55 Warning display process part 56 Graph display process part 500 Mounting unit 510 Connection piping 520 Storage unit 530 Display unit 3A Polishing apparatus (polishing unit)
31A Top ring 202 Top ring body 205 Center chamber 206 Ripple chamber 207 Outer chamber 208 Edge chamber 211 Channel 212 Channel 213 Channel 214 Channel

Claims (4)

An attachment unit to which the top ring body can be attached;
With the top ring body attached to the attachment unit, connection piping connected to the flow path to the pressure chamber of the top ring body,
A fluid supply unit for supplying fluid to the pressure chamber via the connection pipe;
A leak determination unit that determines whether or not a leak has occurred in the pressure chamber based on the change in the pressure and the change in the flow rate when the fluid is supplied to the pressure chamber;
A leak inspection apparatus comprising: A storage unit for storing pressure control data of the fluid when performing a polishing process;
Based on the pressure control data, a pressure control unit that controls a pressure when supplying the fluid to the pressure chamber;
In a state where the pressure when supplying the fluid to the pressure chamber is controlled, a flow rate measuring unit that measures the flow rate of the fluid supplied to the pressure chamber;
The leak inspection apparatus according to claim 1, comprising:   The leak inspection apparatus according to claim 1, further comprising a warning display processing unit that performs processing for warning display when the leak determination unit determines that a leak has occurred in the pressure chamber. .   The graph display process part which performs the process for displaying the change of the said pressure when the said fluid is supplied to the said pressure chamber, and the change of the said flow rate as a graph is provided in any one of Claims 1-3. Leak inspection device.