JP5929035B2 - Substrate transport apparatus, semiconductor manufacturing apparatus, and substrate transport method - Google Patents

Description

  Embodiments relate to a substrate transport technique used in a semiconductor manufacturing apparatus for manufacturing a semiconductor device.

  In recent years, in a semiconductor chip manufacturing process, after a plurality of semiconductor chips are collectively formed on a wafer, the wafer is generally cut and divided (separated) into individual semiconductor chips. Yes.

  In a general process for solidifying a semiconductor chip, first, a protective tape is applied to a circuit forming surface in a state of a single wafer. Thereafter, the wafer is ground back to reduce the wafer to the desired chip thickness. Next, the protective tape affixed to the circuit forming surface is peeled off. Instead, the dicing tape is affixed to the back surface of the wafer, and then the dicing tape is fixed to the ring. And a wafer is cut | disconnected from the circuit formation surface side using a dicing saw, and a semiconductor chip is separated into pieces. Thereafter, the dicing tape is irradiated with ultraviolet rays to reduce the adhesive strength. Then, the semiconductor chip is peeled off from the dicing tape by protruding from the back surface of the semiconductor chip with a needle through the dicing tape. After the semiconductor chip is sucked and taken out by a vacuum pickup, it is transferred to a bonding process or stored in a tray or the like.

  In the above-described process, after the protective tape is applied to the wafer and the back grinding process is performed, the wafer needs to be transported or transferred in the process of attaching the dicing tape or the dicing process. When transferring a wafer, generally, a wafer holder (for example, vacuum tweezers) having a vacuum suction mechanism is used to suck and hold the wafer, and the wafer holder is moved to move the wafer to a desired position. Transport to.

  Vacuum tweezers for adsorbing a wafer generally have a vacuum adsorbing hole or groove formed on a plane for adsorbing the wafer, and a vacuum pump is used as a vacuum generation source. (For example, refer to Patent Document 1). Further, a vacuum tweezer has been proposed in which a negative pressure is generated by jetting compressed air using the Bernoulli theorem as a suction force generation source, and a suction force is generated by this negative pressure (see, for example, Patent Document 2).

  When the above-described vacuum tweezers is used, if the wafer is flat, the entire surface of the wafer can be adsorbed and a sufficient holding force can be obtained. On the other hand, when the wafer has a large warp, the entire surface of the wafer cannot be adsorbed, and for example, only the central portion of the wafer is adsorbed. In this case, a sufficient holding force cannot be obtained, and the wafer may fall away from the vacuum tweezers with a slight impact during the transfer of the wafer. If the holding force is extremely small, the wafer may not be attracted.

  Thus, it has been proposed to hold a wafer by suction using a plurality of movable small suction pads (see, for example, Patent Document 3). When this suction pad is used, even if the wafer is warped, the suction pad can be arranged along the warp of the wafer, and the wafer can be sucked by each of the plurality of suction pads.

JP 2001-35908 A JP 2005-74606 A JP-A-11-79402

  In recent years, the density of semiconductor chips has increased significantly, and the size of semiconductor chips has been reduced. Along with this, the pitch of the protruding electrodes for surface mounting the semiconductor chip on the substrate is also reduced. In addition, the surface mounting bump electrodes are also shifting from the peripheral arrangement to a structure in which the bump electrodes are arranged over the entire mounting surface of the semiconductor chip (so-called area bumps). Such a semiconductor device for surface mounting is obtained by forming a rewiring layer on a single semiconductor chip and forming a protruding electrode on the rewiring layer. In other words, the mounting surface of the semiconductor device is effectively used by arranging the protruding electrodes at appropriate positions by the rewiring layer.

  On the other hand, a technique has been developed in which, when semiconductor chips are formed on a wafer, the electrodes of the semiconductor chip are rewired to form protruding electrodes for surface mounting, and then each semiconductor chip is cut out from the wafer. Such a technique is called a wafer level packaging technique (WLP for short).

  Wafers used in wafer level packaging technology (WLP) are greatly affected by thermal effects and internal stress on the rewiring layer / resin layer, and even when the wafer thickness is as thick as about 200 μm to 400 μm, it is about 5 mm to 20 mm. Wafer warpage is likely to occur. When the wafer thickness is about 200 μm to 400 μm, an action for repelling the force to correct the warp works.

  Therefore, in the conveyance method using the vacuum suction grooves and vacuum suction holes as shown in the above-mentioned Patent Documents 1 and 2, if a vacuum leak occurs from a part of the vacuum suction grooves due to the warpage of the wafer, the entire suction pressure is increased at once. It will be difficult to hold by adsorption. This has a risk of dropping an expensive wafer, which is a very large risk in manufacturing.

  Further, the transport method using the suction pad as shown in Patent Document 3 can cope with a large warp or a step because each suction pad is movable. However, since the warp and the step are transported as they are, when the receiving side at the transport destination is a chuck table, a vacuum leak occurs in the chuck table at the time of delivery, and there is a possibility that it cannot be attracted well. For this reason, it is conceivable that the wafer on which the warpage has occurred is transferred to the chuck table by flattening it using the suction force. However, since the suction pad itself is easily deformed and parts other than the part sucked by the suction pad are deformed, there arises a problem that the entire wafer cannot be flattened.

  Therefore, it is desired to develop a transfer technique that can transfer even a wafer having a large warp and repulsive force while reliably attracting and holding the wafer.

According to one embodiment, the apparatus has a conveyance pick that adsorbs the substrate on the mounting surface and conveys the adsorbed substrate, and a control unit that controls the adsorption holding operation of the substrate by the conveyance pick, The suction surface of the transport pick is a flat surface and is divided into a plurality of areas, and a suction path is provided for each of the plurality of areas, and the controller is configured to suck the substrate on the placement surface. The substrate is brought into contact with the central region of the surface, and the substrate is sucked in the central region, the transport pick is lowered, and the substrate is flattened along the suction surface while pressing the substrate with the suction surface , and the outside of the periphery of the central region There is provided a substrate transport apparatus that controls the suction and holding operation of the substrate by the transport pick so that the region is brought into contact with the substrate and the substrate is sucked in the outer region .

  Moreover, a semiconductor manufacturing apparatus having the above-described substrate transfer apparatus is provided.

Further, the central region of the flat suction surface of the transport pick is brought into contact with the substrate on the mounting surface , the substrate is sucked in the central region, the transport pick is lowered, and the substrate is pushed by the suction surface while pushing the substrate. The substrate is flattened along the suction surface, the outer region around the central region is brought into contact with the substrate, the substrate is sucked in the outer region, and the transport pick holding the substrate is moved to transport the substrate. A substrate transfer method is provided.

While correcting the warp of the substrate is warped toward the peripheral portion can be performed adsorbed from the central portion of the substrate, that Ki out to adsorb the entire substrate is flattened by correcting the warpage of the substrate. As a result, the substrate can be securely held by suction.

It is a figure which shows schematic structure of the semiconductor manufacturing apparatus by one Embodiment. It is the top view which looked at the conveyance pick from the suction surface side. FIG. 3 is a simplified cross-sectional view of a transport pick along the line III-III in FIG. 2. It is the A section enlarged view of FIG. It is a partial expanded sectional view of a chuck table. It is a flowchart of the operation | movement which takes out a wafer from a wafer cassette. It is a figure which shows the state of the wafer in each step of taking-out operation | movement. It is a flowchart of the adsorption | suction fixation operation | movement which mounts and fixes a wafer on a chuck table. It is a figure which shows the state of the wafer in each step of wafer adsorption | suction fixation operation | movement.

  Next, embodiments will be described with reference to the drawings.

  First, a semiconductor manufacturing apparatus according to an embodiment of the present invention will be described. FIG. 1 is a diagram showing a schematic configuration of a semiconductor manufacturing apparatus for manufacturing a semiconductor chip.

  The semiconductor manufacturing apparatus shown in FIG. 1 is a manufacturing apparatus for forming a plurality of semiconductor chips on a wafer as an example of a substrate, cutting the wafer, and solidifying the semiconductor chips, and is provided with a substrate transfer apparatus. The parts are shown. The semiconductor manufacturing apparatus shown in FIG. 1 is, for example, an apparatus for fixing a wafer on a vacuum chuck table inside the apparatus and cutting the wafer with a dicing blade to solidify a plurality of semiconductor chips formed on the wafer. It is. The semiconductor manufacturing apparatus according to the present embodiment is not limited to the semiconductor manufacturing apparatus shown in FIG. 1, and may be a manufacturing apparatus that performs other manufacturing processes such as a process of attaching a protective tape to a wafer.

  A semiconductor manufacturing apparatus 10 shown in FIG. 1 has an apparatus housing 12 for processing a wafer inside. Since the wafer is processed inside the apparatus housing 12, the inside of the apparatus housing 12 is kept in a clean environment and is blocked from the outside. A load board 16 for mounting a wafer cassette 14 containing a wafer is attached to the outside of the apparatus housing 12. At the position where the load board 16 is attached, an opening for taking in and out the wafer is provided.

  Inside the apparatus housing 12, there are a chuck table 20 for mounting and fixing a wafer, and a wafer transfer robot 30 which is a substrate transfer apparatus for taking out the wafer from the wafer cassette 14 and transferring it to the chuck table 20. Has been placed. A transfer pick 40 is attached to the tip of the arm 32 of the wafer transfer robot 30.

  The transport pick 40 holds the wafer accommodated in the wafer cassette 14 on the load board 16 by vacuum suction, transports it as it is to the position of the chuck table 20, and delivers it to the chuck table 20. The chuck table 20 fixes the transferred wafer by vacuum suction, and the wafer is processed on the chuck table 20.

  In order to transfer the wafer using the wafer transfer robot 30, a vacuum suction transfer control device 50 for controlling the vacuum suction of the transfer pick 40 and the vacuum suction of the chuck table 20 is provided. The vacuum suction conveyance control device 50 includes a vacuum source 52 such as a vacuum pump for generating a negative pressure, and a plurality of suction passages for guiding the negative pressure generated by the vacuum source 52 to the conveyance pick 40 and the chuck table. The two suction passages 54A and 54B connect the vacuum source 52 and the transfer pick 40, and the two suction passages 54C and 54D connect the vacuum source 52 and the chuck table 20.

  A substrate transfer device is formed by the wafer transfer robot 30, the transfer pick 40, the vacuum suction control device 50, and the like described above. The substrate transfer device may include the chuck table 20.

  The reason why the vacuum source 52 and the transport pick 40 are connected by the two suction passages 54A and 54B is that, as will be described later, the suction portion of the transport pick 40 is divided into two regions (a central region and an outer region). This is because one suction passage is connected to each of them. Similarly, the reason why the vacuum source 52 and the chuck table 20 are connected by the two suction passages 54C and 54D is that the chucking portion of the chuck table 20 is divided into two regions (a central region and an outer region) as described later. This is because one suction passage is connected to each of them.

  The suction passage 54A connected to the transport pick 40 is provided with a vacuum pressure sensor 56A and a solenoid valve 58A. The suction passage 54B connected to the transport pick 40 is provided with a vacuum pressure sensor 56B and a solenoid valve 58B. The suction passage 54C connected to the chuck table 20 is provided with a vacuum pressure sensor 56C and a solenoid valve 58C. The suction passage 54D connected to the chuck table 20 is provided with a vacuum pressure sensor 56D and a solenoid valve 58D.

  The vacuum suction transfer control device 50 has a controller 60 for controlling opening and closing of solenoid valves 58A, 58B, 58C, 58D. The vacuum pressure sensor 56 </ b> A is disposed between the solenoid valve 58 </ b> A and the transport pick 40 and supplies the detected vacuum pressure to the controller 60. The vacuum pressure sensor 56B is disposed between the solenoid valve 58B and the transport pick 40, and supplies the detected vacuum pressure to the controller 60. The vacuum pressure sensor 56C is disposed between the solenoid valve 58C and the chuck table 20, and supplies the detected vacuum pressure to the controller 60. The vacuum pressure sensor 56D is disposed between the solenoid valve 58D and the chuck table 20 and supplies the detected vacuum pressure to the controller 60.

  Here, the structure of the transport pick 40 will be described. FIG. 2 is a plan view of the transport pick 40 viewed from the suction surface side. The transfer pick 40 has a disk-shaped main body 42 having an outer diameter substantially equal to the wafer to be attracted. An attachment portion 44 extends from one side of the main body 42 and is attached to the arm 32 of the wafer transfer robot 30.

  A large number of suction holes 42b are provided in the suction surface 42a of the main body 42, and the wafer can be sucked and held on the suction surface 42a by the negative pressure introduced into the suction holes 42b. The suction surface 42a is divided into a circular central region 46a having an outer diameter D1 and an annular outer region 46b having an outer diameter D2 outside the central region 46a. The suction hole 42b provided in the central region 46a is connected only to the suction passage 54A and forms a first suction path. On the other hand, the suction hole 42b provided in the outer region 46b is connected only to the suction passage 54B and forms a second suction path. In this embodiment, as will be described later, by controlling the adsorption in the first adsorption path and the adsorption in the second adsorption path, even a wafer with a large warp can be reliably adsorbed and held.

  FIG. 3 is a simplified cross-sectional view of the transport pick 40 taken along line III-III in FIG. FIG. 4 is an enlarged view of part A of FIG.

  Inside the main body 42, a first suction path corresponding to the central region 46a is formed, and a second suction path corresponding to the outer region 46b is formed. In FIG. 3, the first adsorption path and the second adsorption path are indicated by hatching for simplification, and a specific structure is shown in FIG.

  The main body 42 is formed by bonding a suction cover 42B to a main body base 42A. The surface of the main body base 42A becomes the suction surface 42a, and the suction holes 42b are formed in the main body base 42A.

  A suction groove 42Aa is formed in a portion corresponding to the central region 46a of the main body base 42A, and the suction groove 42Aa is closed by a suction cover 42B to form a closed space, and this space is provided in the central region 46a. The suction holes 42b connected to each other are connected. A passage groove 42Ab (see FIG. 2) extending to the attachment portion 44 is connected to the closed space formed by closing the suction groove 42Aa with the suction cover 42B. The opposite end of the passage groove 42Ab is open to the suction surface 42a side in the attachment portion 44. When the transfer pick 40 is attached to the arm of the wafer transfer robot 30, the opening of the passage groove 42Ab is connected to the suction passage 54A. Thereby, a negative pressure is introduced into the suction hole 42b of the central region 46a through the suction passage 54A, the passage groove 42Ab, and the suction groove 42Aa, and the central portion of the wafer can be sucked by the suction action of the suction hole 42b.

  On the other hand, a suction groove 42Ac is formed in a portion corresponding to the outer region 46b of the main body base 42A, and the suction groove 42Ac is closed by a suction cover 42B, and a closed space is formed in this space. Are connected to the suction holes 42b. A passage groove 42Ad (see FIG. 2) extending to the attachment portion 44 is connected to the closed space formed by closing the suction groove 42Ac with the suction cover 42B. The opposite end of the passage groove 42Ad is open to the suction surface 42a side at the attachment portion 44. When the transfer pick 40 is attached to the arm of the wafer transfer robot 30, the opening of the passage groove 42Ad is connected to the suction passage 54B. As a result, negative pressure is introduced into the suction hole 42b of the outer region 46b through the suction passage 54B, the passage groove 42Ad, and the suction groove 42Ac, and the outer peripheral portion around the central portion of the wafer is sucked by the suction action of the suction hole 42b. can do.

  The chuck table 20 has the same structure as the transport pick 40. FIG. 5 is an enlarged cross-sectional view of a part of the chuck table 20. The chuck table 20 includes a chuck table top portion 20A and a chuck table base portion 20B. The upper surface of the chuck table top portion 20A is a suction surface 20a that sucks and fixes the wafer. A large number of suction holes 20b are opened in the suction surface 20a.

  Similar to the transport pick 40, the chuck table 20 also has a central region 26a and an outer region 26b. The suction hole 20b in the central region 26a is connected to the suction groove 20Aa formed in the chuck table top portion 20A, and is connected to the suction passage 54C through the passage groove similarly to the transport pick 40. As a result, negative pressure is introduced into the suction hole 20b of the central region 26a through the third suction path including the suction passage 54C, the passage groove, and the suction groove 20Aa, and the central portion of the wafer is moved by the suction action of the suction hole 20b. Can be adsorbed. Further, the suction hole 20b in the outer region 26b is connected to the suction groove 20Ac formed in the chuck table top portion 20A, and is connected to the suction passage 54D through the passage groove similarly to the transport pick 40. As a result, negative pressure is introduced into the suction hole 20b of the outer region 26b through the fourth suction path including the suction passage 54D, the passage groove, and the suction groove 20Ac. The peripheral part of the periphery can be adsorbed.

  Next, a substrate transport method for transporting a wafer as an example of a substrate in the semiconductor manufacturing apparatus 10 described above will be described.

  First, in the substrate transfer method, a process of taking out a wafer from the wafer cassette 14 and transferring it will be described. FIG. 6 is a flowchart of the operation for taking out the wafer from the wafer cassette 14. FIG. 7 is a diagram showing the state of the wafer in each step of the take-out operation. It is assumed that a plurality of semiconductor chips are formed on the circuit forming surface side of the wafer. Note that the wafer suction holding operation in the following wafer take-out operation is mainly performed under the control of the controller 60.

  When the wafer take-out operation is started, first, in step S1, the wafer transfer robot 30 operates to move the transfer pick 40 over the wafer in the wafer cassette 14 and starts to descend toward the wafer (FIG. 7 ( a)). Here, it is assumed that the wafer to be taken out is warped as shown in FIG. 7A and is stored in the wafer cassette 14 in a state where the central portion is lifted. A protective tape is attached to the lower surface (circuit forming surface) side of the wafer.

  Subsequently, in step S2, the suction surface 42a of the transport pick 40 contacts the highest portion of the central portion of the wafer (see FIG. 7B). At this point, a negative pressure is introduced into the first adsorption path. Specifically, the controller 60 introduces a negative pressure into the first adsorption path by driving the vacuum pump 52 and opening the solenoid valve 58A. As a result, a suction action occurs in the suction hole 42b opened in the central region 46a of the transport pick 40.

  When a suction action is generated in the suction hole 42b in step S2, the central portion of the wafer is sucked into the suction hole 42b. Thereby, in step S3, the central part of the wafer is adsorbed to the adsorption surface 42a. Since the suction surface 42a is a flat surface, the central portion of the wafer becomes flat along the suction surface 42a (see FIG. 7C). At this point, the outer peripheral portion of the wafer remains along, and only the central portion is flattened.

  Subsequently, in step S4, the transport pick 40 further descends and stops at the lowest position. The lowest position is a position where the distance between the transport pick 40 and the wafer cassette 14 is slightly larger than the thickness of the wafer including the protective tape. At this time, the outer peripheral portion of the wafer is pushed by the suction surface 42a of the transport pick 40 and flattened along the suction surface 42a. Therefore, the second suction path is turned on to suck the outer peripheral portion of the wafer onto the suction surface 42a. As a result, the entire wafer is attracted to the attracting surface 42a and flattened (see FIG. 7D). As described above, since the wafer is attracted to the transport pick 40 from the central portion toward the outer peripheral portion, even when the warp is corrected and the wafer spreads, the wafer is not caught due to suction and holding.

  Subsequently, in step S5, the transport pickup 40 is lifted. Since the entire wafer is attracted to the attracting surface 42a, the wafer is held by the transport pick 40 (see FIG. 7E).

  Next, in step S6, the degree of vacuum in the first suction path is confirmed by the vacuum pressure sensor 56A. That is, the vacuum pressure of the first suction path is detected by the vacuum pressure sensor 56A, and it is determined whether or not the first suction path is larger than a predetermined vacuum level. Here, a larger degree of vacuum means that the absolute pressure is smaller when the absolute vacuum is zero. The predetermined degree of vacuum is the degree of vacuum to be generated in the first suction path (suction passage 54A) by evacuation by the vacuum source 52 when the suction hole 42a of the first suction path is closed by the wafer. Or a degree of vacuum close to that.

  If it is determined in step S6 that the first suction path is not greater than the predetermined degree of vacuum (NO in step S6), the process returns to step S4, and the wafer is suctioned again. If it is determined in step S6 that the first suction path is not greater than the predetermined degree of vacuum, it can be determined that the wafer is warped again away from the suction surface 42a. That is, when it is determined that the first suction path is not larger than the predetermined degree of vacuum, as shown in FIG. 7F, the wafer is greatly warped, and the central region is not flat, It can be determined that the suction hole 42a cannot be blocked by the wafer. In such a state, air flows from the suction hole 42a, and the first suction path does not reach a predetermined degree of vacuum. As a matter of course, the second suction path does not reach a predetermined degree of vacuum. Therefore, returning to step S4, the wafer suction is performed again.

  On the other hand, if it is determined in step S6 that the first suction path is greater than the predetermined degree of vacuum (YES in step S6), the process proceeds to step S7. In step S7, the vacuum degree of the second suction path is confirmed by the vacuum pressure sensor 56B. That is, the degree of vacuum of the second suction path is detected by the vacuum pressure sensor 56B, and it is determined whether or not the second suction path is larger than a predetermined degree of vacuum. The predetermined degree of vacuum is the degree of vacuum that should be generated in the second suction path (suction passage 54B) by evacuation by the vacuum source 52 when the suction hole 42a of the second suction path is closed by the wafer. Or a degree of vacuum close to that.

  If it is determined in step S7 that the second suction path is not greater than the predetermined degree of vacuum (NO in step S7), the process proceeds to step S8. When it is determined that the second suction path is not larger than the predetermined degree of vacuum, as shown in FIG. 7G, the outer peripheral portion of the wafer is warped and separated from the suction surface 42a. It can be judged that there is. That is, only the central region of the wafer is attracted and held on the transfer pick 40. In such a state, since the wafer suction holding force is weak, the wafer may fall away from the transport pick 40 with a small impact.

  Therefore, in step S8, the controller 60 sets the moving speed of the transfer pick 40 by the wafer transfer robot 30, that is, the wafer transfer speed, to a low speed. The low speed is a speed smaller than the normal transport speed, and the wafer is separated from the transport pick 40 when the transport pick 40 is accelerated or decelerated or stopped with only the central portion of the wafer being sucked and held. The speed is such that no significant impact or external force is generated. This low speed is preferably determined in advance by experiments or the like.

  When the process in step S8 ends, the process proceeds to step S10, where the transfer pick 40 is moved at a set low speed to start wafer transfer.

  On the other hand, if it is determined in step S8 that the second suction path is greater than the predetermined degree of vacuum (YES in step S7), the process proceeds to step S9. If it is determined that the second suction path is greater than the predetermined degree of vacuum, as shown in FIG. 7H, the central portion and the outer peripheral portion of the wafer are sucked and the entire wafer is sucked to the suction surface 42a. It can be determined that the user is in a state. That is, the entire wafer is sucked and held on the transfer pick 40. In such a state, since the wafer suction holding force is strong, even if a large impact is applied to the transport pick, there is no possibility that the wafer will fall away from the transport pick 40.

  Therefore, in step S9, the controller 60 sets the moving speed of the transfer pick 40 by the wafer transfer robot 30, that is, the wafer transfer speed, to a high speed. High speed is a normal transfer speed, and when the transfer pick 40 is accelerated or decelerated or stopped while the entire wafer is sucked and held, an impact or external force that causes the wafer to move away from the transfer pick 40 is generated. The speed is not. This high speed is preferably determined in advance by experiments or the like.

  When the process in step S9 ends, the process proceeds to step S10, and the transfer pick 40 is moved at a set high speed to start wafer transfer.

  As described above, according to the present embodiment, even if a wafer is warped, the entire wafer is sucked while partially sucking and flattening the wafer. The whole can be adsorbed. Also, if the suction becomes incomplete due to warpage and only a part of the wafer is sucked, the wafer can be transported without dropping by setting the transport speed to a low speed commensurate with the suction force. it can.

  In this embodiment, the suction surface 42a of the transport pick 40 is divided into two regions and independent suction paths are provided for each. However, the suction surface 42a is divided into three or more concentric regions. Independent adsorption paths may be provided for each of them.

  For example, in the transfer of a WLP wafer having a large repulsive force, a plurality of transfer pick vacuum suction paths are provided so that the flattening of the wafer proceeds from the center to the periphery. Further, the wafer is flattened from the center toward the periphery by the vertical movement of the transfer pick. As a result, even a WLP wafer having a large repulsive force can be reliably sucked and held by the transfer pick. And, by performing the re-adsorption operation while grasping the adsorption state using the pressure information detected in the plurality of vacuum adsorption paths, or changing the conveyance speed, more reliable and stable conveyance can be realized. it can. In addition, the stress on the semiconductor chip formed on the wafer can be suppressed and the quality of the semiconductor chip can be improved.

  Next, in the semiconductor manufacturing apparatus 10 described above, a process of mounting and fixing the wafer transferred by the transfer pick 40 on the chuck table 20 will be described. FIG. 8 is a flowchart of the operation of placing and fixing the wafer on the chuck table 20. FIG. 9 is a diagram showing the state of the wafer in each step of the wafer suction fixing operation for placing and fixing the wafer on the chuck table 20. A plurality of semiconductor chips are formed on the circuit forming surface side of the wafer, and a protective tape is attached to the circuit forming surface side. Note that the wafer suction fixing operation described below is mainly performed under the control of the controller 60.

  When the wafer picking robot 40 moves the pick picking and holding the wafer to the position just above the chuck table 20, when the wafer mounting and fixing operation is started, first, in step S11, the pick pick is placed on the chuck table 20. Starts to descend (see FIG. 9A). Here, even if the wafer to be mounted is a wafer that has warped, the entire wafer is attracted to the transfer pick 40, so that the warp is corrected as shown in FIG. It is flattened.

  The transport pick 40 descends toward the chuck table 20 and stops at the lowest position in step S12. When the transport pick 40 is lowered to the lowest position, the wafer protective tape sucked and held on the suction surface 42a of the transport pick 40 is in contact with or very close to the suction surface 20a of the chuck table 20 (FIG. 9 (b)). Therefore, after the third suction path of the chuck table 20 is turned on and wafer suction is started, the first suction path and the second suction path of the transport pick 40 are turned off to release the wafer suction. As a result, the central portion of the wafer is sucked by the suction hole 20 b provided in the central region of the suction surface 20 a of the chuck table 20.

  Subsequently, after a predetermined time has elapsed since the third suction path is turned on, in step S13, the fourth suction path of the chuck table 20 is turned on, and then the first suction path and the second suction path of the transport pick 40 are turned on. Perform vacuum break blow in the path. As a result, the entire wafer is separated from the transfer pick 40, and the outer peripheral portion is also sucked after the central portion of the wafer is sucked by the chuck table 20 (see FIG. 9C). As described above, since the wafer is attracted to the chuck table 20 from the central portion toward the outer peripheral portion, even when the warp is corrected and the wafer spreads, the wafer is not caught by suction and holding.

  Subsequently, in step S14, the transport pick 40 is raised and the vacuum break blow is turned off. The wafer remains on the chuck table 20 while being fixed to the chuck table 20 (see FIG. 9D).

  Subsequently, in step S15, the degree of vacuum in the third suction path and the fourth suction path is confirmed by the vacuum pressure sensors 56C and 56D. That is, the degree of vacuum of the third adsorption path is detected by the vacuum pressure sensor 56C, it is determined whether or not the third adsorption path is larger than a predetermined degree of vacuum, and the degree of vacuum of the fourth adsorption path is determined by the vacuum pressure sensor 56D. The degree of vacuum is detected, and it is determined whether or not the fourth suction path is greater than a predetermined degree of vacuum.

  If it is determined that the degree of vacuum in either the third suction path or the fourth suction path is not greater than the predetermined vacuum degree (NO in step S15), the process returns to step S12, and the transport pick 40 is lowered to the lowest level. After being lowered to the position, the wafer is again sucked onto the chuck table 20. For example, if the degree of vacuum of the fourth suction path is not greater than a predetermined degree of vacuum, it can be determined that the outer peripheral portion of the wafer is not completely sucked as shown in FIG. . Therefore, suction is performed again while the wafer is pushed and flattened by the transport pick 40.

  On the other hand, if it is determined that the degree of vacuum in both the third adsorption path and the fourth adsorption path is greater than the predetermined degree of vacuum (YES in step S15), the process proceeds to step S16. If the degree of vacuum in both the third suction path and the fourth suction path is greater than a predetermined vacuum degree, it is determined that the entire wafer is suction-fixed to the chuck table as shown in FIG. In step S16, processing on the wafer is started.

  As described above, according to the present embodiment, even if the wafer is warped, the wafer that has been flattened while being partially attracted is placed on the chuck table 20 as it is and is flattened. Since the entire wafer is sucked by the chuck table 20 while maintaining the above, the entire wafer can be sucked while correcting the warp.

  In this embodiment, the suction surface 20a of the chuck table 20 is divided into two regions and an independent suction path is provided for each. However, the suction surface 30a is divided into three or more concentric regions. Independent adsorption paths may be provided for each of them.

  For example, in the suction fixing of a WLP wafer having a large repulsive force, a plurality of chuck table vacuum suction paths are provided so that the wafer suction proceeds from the center toward the periphery. Further, the wafer is attracted from the center toward the periphery while the wafer is pressed and flattened by the transfer pick. As a result, even a WLP wafer having a large repulsive force can be securely fixed to the chuck table. Then, by performing the re-adsorption operation while grasping the adsorption state using the pressure information detected by the plurality of vacuum adsorption paths, more reliable and stable adsorption fixation can be realized.

As described above, the present specification discloses the following matters.
(Appendix 1)
A transport pick for transporting while holding the substrate,
A control unit for controlling the suction holding operation of the substrate by the transport pick,
The suction surface of the transport pick is divided into a plurality of areas, and a suction path is provided for each of the plurality of areas.
The said control part is a board | substrate conveyance apparatus which controls the adsorption | suction holding | maintenance operation | movement of the board | substrate by the said conveyance pick by controlling the negative pressure introduced into the said adsorption | suction path | route.
(Appendix 2)
A substrate transfer apparatus according to appendix 1, wherein
The adsorption path is connected to a vacuum source via a suction path;
An opening / closing valve is provided in the suction passage;
The control unit controls the operation of the vacuum source and the operation of the on-off valve to control the operation of holding and holding the substrate by the transport pick.
(Appendix 3)
A substrate transfer apparatus according to appendix 2, wherein
A vacuum pressure sensor is provided in the suction passage;
The control unit is a substrate transfer device that determines an adsorption state of the substrate based on a pressure detected by the vacuum pressure sensor.
(Appendix 4)
A substrate transfer apparatus according to appendix 2, wherein
A vacuum pressure sensor is provided in the suction passage;
The control unit is a substrate transfer apparatus that sets a transfer speed of the substrate based on a pressure detected by the vacuum pressure sensor.
(Appendix 5)
The substrate transfer apparatus according to any one of appendices 1 to 4,
A chuck table for adsorbing and fixing the substrate transported by the transport pick;
A substrate transport apparatus in which a suction surface of the chuck table is divided into a plurality of regions, and a suction path is provided for each of the plurality of regions.
(Appendix 6)
The substrate transfer apparatus according to appendix 5, wherein
The suction path of the chuck table is connected to a vacuum source through a suction path,
An opening / closing valve is provided in the suction passage;
The control unit controls the operation of the vacuum source and the operation of the on-off valve to control the operation of adsorbing and fixing the substrate by the chuck table.
(Appendix 7)
The substrate transfer apparatus according to appendix 6, wherein
A vacuum pressure sensor is provided in the suction passage;
The control unit is a substrate transfer device that determines an adsorption state of the substrate to the chuck table based on a pressure detected by the vacuum pressure sensor.
(Appendix 8)
A semiconductor manufacturing apparatus comprising the substrate transfer apparatus according to any one of appendices 1 to 7.
(Appendix 9)
The central region of the suction surface of the transport pick is brought into contact with the substrate, and the substrate is sucked in the central region,
Lowering the transport pick, bringing the outer region around the central region into contact with the substrate, adsorbing the substrate in the outer region,
A substrate transport method for transporting the substrate by moving a transport pick holding the substrate by suction.
(Appendix 10)
The substrate transfer method according to appendix 9, wherein
After adsorbing the substrate in the outer region, raising the transport pick,
A substrate transfer method in which the suction in the central region and the suction in the outer region are repeated when the vacuum pressure in the suction path connected to the suction hole in the central region is not greater than a predetermined vacuum pressure.
(Appendix 11)
The substrate transfer method according to appendix 9, wherein
After adsorbing the substrate in the outer region, raising the transport pick,
When the vacuum pressure in the suction path connected to the suction hole in the central region is greater than a predetermined vacuum pressure, and the vacuum pressure in the suction path connected to the suction hole in the outer region is not greater than a predetermined vacuum pressure, the transfer A substrate transfer method in which the moving speed of the pick is set to a lower speed than the normal moving speed.
(Appendix 12)
The substrate transfer method according to appendix 9, wherein
After adsorbing the substrate in the outer region, raising the transport pick,
When the vacuum pressure in the suction path connected to the suction hole in the central region is larger than a predetermined vacuum pressure and the vacuum pressure in the suction path connected to the suction hole in the outer region is larger than a predetermined vacuum pressure, the transport pick A substrate transfer method in which the moving speed is set to the normal moving speed.

DESCRIPTION OF SYMBOLS 10 Semiconductor manufacturing apparatus 12 Apparatus housing 14 Wafer cassette 16 Load board 20 Chuck table 20A Chuck table top part 20Aa, 20Ac Adsorption groove | channel 20a Adsorption surface 20b Adsorption hole 26a Central area | region 26b Outer area | region 30 Wafer transfer robot 32 Arm 40 Transfer pick 42 Main body 42a Suction surface 42b Suction hole 42A Main body base 42Aa, 42Ac Suction groove 42Ab, 42Ad Passage groove 42B Suction cover 44 Mounting portion 46a Central region 46b Outer region 50 Vacuum suction transport control device 52 Vacuum source 54A, 54B, 54C, 54D Suction passage 56A , 56B, 56C, 56D Vacuum pressure sensor 58A, 58B, 58C, 58D Solenoid valve 60 Controller

Claims (6)

A pick picking up the substrate on the mounting surface and carrying the picked up substrate while holding it;
A control unit for controlling the suction holding operation of the substrate by the transport pick,
The suction surface of the transport pick is a flat surface and is divided into a plurality of areas, and a suction path is provided for each of the plurality of areas.
The control unit brings the substrate on the placement surface into contact with a central region of the suction surface , sucks the substrate in the central region, lowers the transport pick and pushes the substrate on the suction surface A substrate transport apparatus that controls the suction holding operation of the substrate by the transport pick so as to flatten along the suction surface, bring the outer region around the central region into contact with the substrate, and suck the substrate in the outer region. . The substrate transfer apparatus according to claim 1,
The adsorption path is connected to a vacuum source via a suction path;
An opening / closing valve is provided in the suction passage;
The control unit controls the operation of the vacuum source and the operation of the on-off valve to control the operation of holding and holding the substrate by the transport pick. The substrate transfer apparatus according to claim 2,
A vacuum pressure sensor is provided in the suction passage;
The control unit is a substrate transfer device that determines an adsorption state of the substrate based on a pressure detected by the vacuum pressure sensor. The substrate transfer apparatus according to claim 2,
A vacuum pressure sensor is provided in the suction passage;
The control unit is a substrate transfer apparatus that sets a transfer speed of the substrate based on a pressure detected by the vacuum pressure sensor.   The semiconductor manufacturing apparatus which has a board | substrate conveyance apparatus as described in any one of Claims 1 thru | or 4. The central area of the flat suction surface of the transport pick is brought into contact with the substrate on the mounting surface, and the substrate is sucked in the central area,
The transport pick is lowered and flattened along the suction surface while pushing the substrate at the suction surface, the outer region around the central region is brought into contact with the substrate, and the substrate is sucked at the outer region,
A substrate transport method for transporting the substrate by moving a transport pick holding the substrate by suction.

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