JP5670682B2 - Wafer processing apparatus, wafer processing method, and semiconductor device manufacturing method - Google Patents

Description

  The present invention relates to a semiconductor manufacturing technique for processing a plurality of semiconductor wafers.

  In the semiconductor device manufacturing process, in order to improve productivity, a plurality of semiconductor wafers (hereinafter simply referred to as “wafers”) are placed and held on the surface of a single wafer holder. Processes such as ion implantation and polishing may be performed all at once.

  For example, in Japanese Patent Application Laid-Open No. 07-326317 (Patent Document 1), a plurality of wafers are held on the surface of a single disk which is a wafer holder, and an ion beam is uniformly applied to the wafer on the disk while rotating the disk. An ion implantation apparatus for irradiating a laser beam is disclosed. In Japanese Patent Laid-Open No. 11-233468 (Patent Document 2), polishing is performed by holding a plurality of wafers on a holding plate (wafer holder), and the wafers are stored in a wafer storage cassette from the holding plate after polishing. An automatic wafer collection method is disclosed.

Japanese Unexamined Patent Publication No. 07-326317 (for example, FIG. 1, paragraphs 0006 to 0007) Japanese Patent Laid-Open No. 11-233468 (for example, FIG. 1, paragraphs 0010 to 0016)

  After the processing of a plurality of wafers held on the wafer holder is completed, a control process is generally performed to replace all processed wafers on the wafer holder with unprocessed wafers using a robot arm. However, there is a problem that the processed wafer remaining on the wafer holder is processed again due to failure to replace a part of the plurality of processed wafers, resulting in defective products.

  In view of the above, an object of the present invention is to provide a wafer processing apparatus and a wafer processing method capable of preventing the generation of defective products even when replacement of a processed wafer on a wafer holder fails.

A wafer processing apparatus according to the present invention has a plurality of pedestal, the wafer holder having a detected portion which is formed at a position corresponding to one of the plurality of pedestal, respectively mounted on the mounting surface of the plurality of pedestal A wafer processing mechanism for performing processing on the plurality of wafers, and rotating the wafer holder after the processing has been performed to sequentially position the plurality of pedestals at a predetermined removal position, and from the positioned pedestals A wafer transfer mechanism that removes the wafer and then places an unprocessed wafer on the pedestal, a wafer transfer control unit that controls the operation of the wafer transfer mechanism, and the pedestal that is the surface opposite to the mounting surface The wafer holder is rotated by the wafer transfer mechanism based on a pattern provided on the back surface of the wafer. Shown in the pedestal sensor for detecting the pedestal, when one of the plurality of pedestal is positioned at the detachment position, the position of the detected portion is, whether or not equal to a predetermined reference position A detected portion detection sensor that outputs a determination signal to the wafer transfer control unit, and the wafer transfer control unit sets a variable from a predetermined initial value every time the pedestal is detected by the pedestal detection sensor. When the variable is determined to be equal to the total number of the plurality of pedestals of the wafer holder, and the position of the detected portion is determined not to match the reference position based on the determination signal characterized that you output a signal.

Holder wafer processing method according to the invention, which has a plurality of pedestal which a plurality of wafers are placed on the placement surface, respectively, having a detected portion which is formed at a position corresponding to one of the plurality of pedestal A step of performing processing on the plurality of wafers, and rotating the wafer holder after the processing is performed to sequentially position the plurality of pedestals at a predetermined removal position, and from the positioned pedestals In the step of placing an unprocessed wafer on the pedestal after removing the wafer and the step of placing the unprocessed wafer, the back surface of the pedestal that is the surface opposite to the placement surface is provided. a step of based on the pattern, is detected using the pedestal detecting sensor said pedestal of said wafer holder for rotating, When any of the serial plurality of pedestal is positioned at the detachment position, the position of the detected portion with a detected portion detecting sensor, and determining whether matches a predetermined reference position And a variable that increments by one from a predetermined initial value every time the pedestal is detected by the pedestal detection sensor is equal to the total number of the plurality of pedestals that the wafer holder has, the determination characterized Rukoto alarm signal is output when the is determined that the position of the detected portion does not coincide with the reference position based on the signal.

  A method of manufacturing a semiconductor device according to the present invention includes the steps of the wafer processing method.

  According to the present invention, when any of the pedestals of the wafer holder is positioned at the removal position and the detected position of the detected portion of the wafer holder does not match the reference position, the replacement of the processed wafer has failed. Therefore, the operation of the wafer transfer mechanism can be stopped. Therefore, since the processed wafer is prevented from being processed again, it is possible to reliably prevent the manufacture of a defective semiconductor device.

It is a figure which shows schematically the structure of the ion implantation apparatus (wafer processing apparatus) of this Embodiment. It is a figure which shows the detailed structure of the wafer conveyance mechanism of this Embodiment. It is a schematic sectional drawing in alignment with the III-III line of the wafer holder of FIG. It is a flowchart which shows roughly the process sequence of the sequence control by a wafer conveyance control part. 6 is a flowchart schematically showing a procedure of wafer carry-in processing (step S11) in FIG. 5 is a flowchart schematically showing a procedure of a wafer carry-in / out process (step S18) in FIG. It is a figure which shows the 1st state of a wafer conveyance mechanism. It is a figure which shows the 2nd state of a wafer conveyance mechanism. It is a figure which shows the 3rd state of a wafer conveyance mechanism. It is a figure which shows the 4th state of a wafer conveyance mechanism. It is a figure which shows the 5th state of a wafer conveyance mechanism. It is a figure which shows the 6th state of a wafer conveyance mechanism.

  Embodiments according to the present invention will be described below with reference to the drawings.

  FIG. 1 is a diagram schematically showing a configuration of an ion implantation apparatus (wafer processing apparatus) 1 according to the present embodiment. As shown in FIG. 1, the ion implantation apparatus 1 generates an ion beam IB from an element and irradiates a wafer holder in an end station unit (sample chamber) 50, and an ion beam irradiation mechanism 20 to the end station unit 50. A wafer transfer mechanism 30 that loads and unloads the wafer, and a system controller 60 that controls the operations of the ion beam irradiation mechanism 20 and the wafer transfer mechanism 30 are included. The administrator can cause the system controller 60 to execute control processing by operating the operation panel 63.

  FIG. 2 is a diagram showing a more detailed configuration of the wafer transfer mechanism 30. As shown in FIG. 2, the wafer transfer mechanism 30 includes a holder mounting portion to which two wafer holders 31 and 33 each having a disk shape are detachably mounted, and an exchange for exchanging the positions of the wafer holders 31 and 33 with each other. Arms 34A and 34B are provided.

  One wafer holder 31 has a plurality of pedestals (wafer mounting bases) P1 to P13 arranged in a ring around the rotation axis of the wafer holder 31, and these pedestals P1 to P13 are respectively mounted on the wafers placed thereon. It has a function of adsorbing and holding the back surface. The wafer holder 31 has a slit hole 31s penetrating from the front surface side to the back surface side in a region between a pair of adjacent pedestals P1 and P13. The slit hole 31s is formed to allow the Faraday cup (not shown) to detect the ion beam IB during the ion implantation process. The system controller 60 has a function of measuring the ion beam current from the detection result of the Faraday cup and controlling the ion implantation amount (dose amount) to the wafer based on the measurement result. The other wafer holder 33 also has a plurality of pedestals Q1 to Q13 arranged in a ring around the rotation axis of the wafer holder 33. These pedestals Q1 to Q13 adsorb the back surface of the mounted wafer. Has the function of holding. The wafer holder 33 has a slit hole 33s penetrating from the front surface side to the back surface side in a region between a pair of adjacent pedestals Q1 and Q13. The structure of the wafer holder 33 is the same as that of the wafer holder 31.

  A holder driving unit 32 is provided immediately below the wafer holder 31. The holder driving unit 32 rotates the wafer holder 31 in the clockwise direction under the control of the wafer transfer control unit 62. The rotational direction positions of the pedestals P1 to P13 of the wafer holder 31 are detected by pedestal detection sensors 37A and 37B. An uneven pattern (not shown) is formed on each of the back surfaces of the pedestals P1 to P13. The pedestal detection sensors 37 </ b> A and 37 </ b> B detect the concavo-convex pattern passing immediately above the pedestal detection sensors 37 </ b> A and 37 </ b> B and output the detection result to the wafer transfer control unit 62. The wafer transfer control unit 62 can control the rotational position of the pedestals P1 to P13 with respect to the carry-out arm 43A and the carry-in arm 43B using the detection result. The pedestal detection sensors 37 </ b> A and 37 </ b> B are non-contact sensors, for example, a light emitting element such as a light emitting diode that emits light toward the back surface of the wafer holder 31, and reflected light from the back surface to receive an electrical signal. It is possible to employ a reflection type optical sensor including a light receiving element. Alternatively, capacitive proximity switches may be employed as the pedestal detection sensors 37A and 37B.

  Immediately below the exchange arms 34A, 34B are provided arm drive units 35A, 35B for driving the exchange arms 34A, 34B, respectively. The exchange arms 34A and 34B are driven by the arm driving portions 35A and 35B, respectively, so that the positions of the wafer holders 31 and 33 can be interchanged.

  FIG. 3 is a schematic cross-sectional view of the wafer holder 31 of FIG. 2 taken along line III-III. As shown in FIG. 3, the wafer holder 31 has a slit hole (detected portion) 31 s penetrating from the front surface side to the back surface side of the wafer holder 31. The slit detection sensor 38 is a non-contact sensor, for example, a light emitting element such as a light emitting diode that emits light toward the back surface of the wafer holder 31, and a light receiving device that receives reflected light from the back surface and converts it into an electrical signal. A reflective optical sensor including an element can be employed. Alternatively, a capacitive proximity switch may be employed as the slit detection sensor 38, but a reflective optical sensor is more desirable than a proximity switch from the viewpoint of facilitating sensitivity adjustment.

  The wafer transfer control unit 62 can detect whether or not the rotational position of the slit hole 31 s matches the reference position based on the output (determination signal) of the slit detection sensor 38. When a reflective optical sensor is used as the slit detection sensor 38, the output light of the slit detection sensor 38 when the rotational direction position of the slit hole 31s matches the reference position as shown in FIGS. Passes through the slit hole 31s, and the slit detection sensor 38 does not detect the reflected light, so the output of the slit detection sensor 38 is at a low level. On the other hand, when the rotational direction position of the slit hole 31s does not coincide with the reference position, the slit detection sensor 38 detects the reflected light from the back surface of the wafer holder 31, so the output of the slit detection sensor 38 is at a high level.

  As shown in FIG. 2, the wafer transfer mechanism 30 includes a loading wafer carrier 41 </ b> B that stores a plurality of unprocessed wafers Wu, a loading arm 43 </ b> B that places the unprocessed wafers Wu on the wafer holder 31, and a loading wafer. A transport belt 42B that transports unprocessed wafers Wu output from the carrier 41B in units of one sheet to a position immediately below the loading arm 43B. The carry-in arm 43B has a distal end portion that can be expanded and contracted with respect to the wafer holder 31, and this distal end portion sucks and holds the unprocessed wafer Wu on the transport belt 42B by a vacuum chuck, and a predetermined attachment of the pedestals P1 to P13. It has a function of placing the unprocessed wafer Wu on a pedestal positioned at a position (in the present embodiment, a position closest to the tip of the loading arm 43B). The wafer transfer mechanism 30 also includes a carry-out arm 43A for removing the processed wafer from the wafer holder 31, a carry-out wafer carrier 41A for storing the processed wafer, and a carry-out wafer carrier 41A for removing the processed wafer removed by the carry-out arm 43A. A conveyor belt 42A that transports the The carry-out arm 43A has a distal end portion that can be expanded and contracted with respect to the wafer holder 31, and this front-end portion is located at a predetermined removal position (in this embodiment, at the distal end portion of the carry-out arm 43A) among the pedestals P1 to P13. It has a function of sucking and holding a processed wafer (not shown) on a pedestal positioned at a close position by a vacuum chuck and placing the processed wafer on the transfer belt 42A.

  The wafer transfer control unit 62 places the unprocessed wafers Wu on the pedestals P1 to P13 on the wafer holder 31 and then exchanges the positions of the wafer holders 31 and 33 with each other using the exchange arms 34A and 34B. Then, as shown in FIG. 1, the wafer transfer control unit 62 raises the wafer holder 31 on which the unprocessed wafer Wu is placed and held on the end station unit 50, and moves the wafer placement surface of the wafer holder 31 to the ion beam irradiation mechanism. Control is directed to 20 directions. The ion beam irradiation mechanism 20 irradiates the wafer holder 31 with the ion beam IB.

  As shown in FIG. 1, the main part of the ion beam irradiation mechanism 20 includes a high voltage power source 21, an ion source 22, an ion acceleration unit 23, a beam transport unit 24, a mass analyzer 25, and a beam shaping unit 26. . The ion source 22 causes arc discharge using the high voltage supplied from the high voltage power source 21 to turn the source gas into plasma. The plasma source gas is extracted as an ion beam by an extraction electrode (not shown). The mass analyzer 25 has a group of magnets that selectively reach the beam shaping unit 26 from the ion beam that passes through the beam transport unit 24. The beam shaping unit 26 focuses the ion beam IB made of the selected ion species and makes it incident on the wafer on the wafer holder 31.

  Wafer holder 31 is held by holder support 51. The holder driving unit 52 includes a rotation motor that rotates the holder supporting unit 51 and a feed mechanism for positioning the wafer holder 31 in the radial direction. The end station control unit 61 controls the holder driving unit 52 to rotate the wafer holder 31 at a high speed and displace it in the radial direction so that a plurality of wafers on the wafer holder 31 are uniformly irradiated with the ion beam IB. Can do. At this time, a part of the ion beam IB passes through the slit hole 31s of the wafer holder 31 and is detected by a Faraday cup (not shown). The system controller 60 has a dose control function of measuring the ion beam current from the detection result of the Faraday cup and controlling the ion implantation amount (dose amount) to the wafer based on the measurement result.

  The wafer transfer operation by the ion implantation apparatus 1 having the above configuration will be described below with reference to FIGS. 4 to 6 are a group of flowcharts schematically showing a processing procedure of sequence control by the wafer transfer control unit 62 for the wafer transfer mechanism 30. FIG. 4 is a flowchart showing the main routine of this sequence control, FIG. 5 is a flowchart schematically showing the procedure of the wafer carry-in process (step S11) in the main routine of FIG. 4, and FIG. 4 is a flowchart schematically showing a procedure of a wafer carry-in / out process (step S18) in the main routine of FIG.

  First, the wafer transfer control unit 62 executes a wafer carry-in process for placing an unprocessed wafer Wu on the wafer holder 31 (step S11). That is, the wafer transfer control unit 62 rotates the wafer holder 31 placed on the wafer carry-in / out side as shown in FIG. 2 in the clockwise direction, based on the output signal of the pedestal detection sensor 37A on the carry-out side. By positioning the pedestal P1 at the removal position (position closest to the tip of the carry-out arm 43A), the rotational position of the wafer holder 31 is initialized (step S111 in FIG. 5). Here, the level of the output signal of the pedestal detection sensor 37A on the carry-out side changes when the slit hole 31s passes immediately above the pedestal detection sensor 37A and when the uneven pattern on the back surface of the pedestal passes. Therefore, the wafer transfer control unit 62 monitors the output signal of the pedestal detection sensor 37A, changes the level of the output signal waveform corresponding to the slit hole 31s, and changes the level of the output signal waveform corresponding to the uneven pattern on the back surface of the pedestal. , The rotation of the wafer holder 31 can be stopped and the first pedestal P1 can be positioned at the mounting position. Next, the wafer transfer control unit 62 sets the variable i to “1” (step S112 in FIG. 5).

  Next, the wafer transfer control unit 62 rotates the wafer holder 31 in the clockwise direction, and places the i-th pedestal Pi on the attachment position (most at the tip of the loading arm 43B) based on the output signal of the loading-side pedestal detection sensor 37B. (Close position) (step S113 in FIG. 5). Here, the level of the output signal of the pedestal detection sensor 37B on the carry-in side changes when the uneven pattern on the back surface of the pedestal passes just above the pedestal detection sensor 37B. Therefore, the wafer transfer control unit 62 monitors the output signal of the pedestal detection sensor 37B, stops the rotation of the wafer holder 31 when the level change of the output signal waveform corresponding to the uneven pattern occurs, and attaches the pedestal Pi Can be positioned. Then, the wafer transfer control unit 62 places the unprocessed wafer Wu on the pedestal Pi using the carry-in arm 43B (step S114 in FIG. 5).

  Next, the wafer transfer control unit 62 determines whether or not the variable i has reached the pedestal total number N (N = 13 in the present embodiment) of the wafer holder 31 (step S115 in FIG. 5). If not reached, i is incremented by 1 (step S116 in FIG. 5), and the process returns to step S113. On the other hand, if i has reached N (YES in step S115 of FIG. 5), the wafer transfer control unit 62 determines that the wafer carry-in process has been completed and shifts the process to the main routine of FIG. At this time, as shown in FIG. 7, the unprocessed wafer Wu is placed on all the pedestals of the wafer holder 31.

  Next, the wafer transfer control unit 62 uses the replacement arms 34A and 34B to exchange positions of the wafer holder 31 on which the unprocessed wafer Wu is placed and the wafer holder 33 on which the wafer is not yet placed (steps). S12). As a result, as shown in FIG. 8, the wafer holder 33 is disposed on the wafer carry-in / out side, and the wafer holder 31 is disposed on the end station 50 side.

  Next, the wafer transfer control unit 62 notifies the end station control unit 61 that the disk replacement process (step S12) has been completed (step S13). Subsequently, the wafer transfer control unit 62 places the unprocessed wafer Wu on all the pedestals Q1 to Q13 of the wafer holder 33 by executing the same wafer carry-in process as that in step S11 on the wafer holder 33 (step S14). ). In parallel with the wafer carry-in process (step S14), the end station control unit 61 raises the wafer holder 31 to the end station unit 50 and performs the ion beam irradiation mechanism 20 on the wafer holder 31 as shown in FIG. The wafer Wu is irradiated with an ion beam IB. The wafer transfer control unit 62 is on standby until the ion implantation process for the wafer holder 31 is completed (NO in step S15).

  When the ion implantation process is completed (YES in step S15), the end station control unit 61 returns the wafer placement surface of the wafer holder 31 to the original horizontal state. Thereafter, as shown in FIG. 10, the wafer transfer control unit 62 uses the replacement arms 34A and 34B, the wafer holder 33 on which the unprocessed wafer Wu is mounted, and the wafer holder 31 on which the processed wafer Wp is mounted. Are exchanged with each other (step S16). Next, the wafer transfer controller 62 notifies the end station controller 61 that the disk replacement (step S16) has been completed (step S17).

  Thereafter, the wafer transfer control unit 62 executes a wafer carry-in / out process for replacing the processed wafer Wp on the wafer holder 31 with the unprocessed wafer Wu (step S18). That is, the wafer transfer control unit 62 rotates the wafer holder 31 placed on the wafer carry-in / out side in the clockwise direction, and removes the first pedestal P1 based on the output signal of the carry-out pedestal detection sensor 37A. By positioning it at the position closest to the tip of the carry-out arm 43A, the rotational direction position of the wafer holder 31 is initialized (step S181 in FIG. 6). At this time, the wafer transfer control unit 62 monitors the output signal of the pedestal detection sensor 37A, changes the level of the output signal waveform corresponding to the slit hole 31s, and changes the level of the output signal waveform corresponding to the uneven pattern on the back surface of the pedestal. , The rotation of the wafer holder 31 can be stopped and the first pedestal P1 can be positioned at the removal position. Next, the wafer transfer control unit 62 sets the variable i to “1” (step S182 in FIG. 6).

  Next, the wafer transfer control unit 62 removes the processed wafer Wp from the first pedestal P1 using the carry-out arm 43A, and collects the processed Wp in the carry-out wafer carrier 41A (step S183).

  Next, the wafer transfer control unit 62 rotates the wafer holder 31 in the clockwise direction, positions the i-th pedestal Pi at the attachment position based on the output signal of the loading-side pedestal detection sensor 37B, and the i + 1-th pedestal P ( i + 1) is positioned at the removal position (step S184 in FIG. 6). At this time, the wafer transfer control unit 62 monitors the output signal of the pedestal detection sensor 37B, and stops the rotation of the wafer holder 31 when the level change of the output signal waveform corresponding to the uneven pattern on the back surface of the pedestal occurs. Pi can be positioned at the wafer mounting position. In addition to the output signal of the pedestal detection sensor 37B, using the output signal of the pedestal detection sensor 37A, the wafer transfer control unit 62 positions the pedestal Pi at the mounting position, and moves the pedestal P (i + 1) to the removal position. It may be positioned.

  Then, when the variable i has not reached the pedestal total number N (NO in step S185), the wafer transfer control unit 62 removes the processed wafer Wp from the (i + 1) th pedestal P (i + 1) using the carry-out arm 43A, The processed Wp is collected by the unloading wafer carrier 41A, and the unprocessed wafer Wu is placed on the i-th pedestal Pi using the loading arm 43B (step S186). Next, the wafer transfer control unit 62 increments the variable i by 1 (step S187), and shifts the processing to step S184.

  When it is determined in step S185 that the variable i has reached the total number N of pedestals (YES in step S185), the wafer transfer control unit 62 places the unprocessed wafer Wu on the Nth pedestal PN using the transfer arm 43B. (Step S188).

  In parallel with the above steps S181 to S188, the end station control unit 61 raises the wafer holder 33 to the end station unit 50 and performs the ion beam irradiation mechanism 20 on the wafer holder 33 as shown in FIG. The wafer Wu is irradiated with an ion beam IB.

  When the above process is performed without error, the rotational direction position of the slit hole 31s is the same as the reference position (position in the initial state) immediately above the slit detection sensor 38 as shown in FIG. 12 when step S188 is completed. I'm doing it. At this time, the output of the slit detection sensor 38 becomes a low level (NO in step S189), and in response to this, the wafer transfer control unit 62 returns the process to the main routine of FIG. Thereafter, when the sequence control process is not terminated (NO in step S19), the wafer transfer control unit 62 executes steps S15 to S18 again. On the other hand, if it is determined that the sequence control process is to be ended (YES in step S19), the wafer transfer control unit 62 ends the sequence control process.

  However, when the concavo-convex pattern on the back surface of the pedestal deteriorates or foreign matter adheres to the concavo-convex pattern, the pedestal detection sensors 37A and 37B may fail to detect the concavo-convex pattern. At this time, the wafer transfer control unit 62 fails to initialize the rotational position of the wafer holder 31 (step S181), or moves the i + 1-th pedestal P (i + 1) on which the processed wafer Wp is placed to the removal position. There arises a problem that positioning (step S184) fails. When such a problem occurs, the rotation direction position of the slit hole 31s does not coincide with the reference position immediately above the slit detection sensor 38 when the processing of steps S181 to S188 is completed, so that the output of the slit detection sensor 38 is at a high level. (YES in step S189). At this time, the wafer transfer control unit 62 outputs an alarm signal in response to the high level output of the slit detection sensor 38 (step S190). In response to the alarm signal, the light emitting unit 64 emits light and the speaker 65 outputs a warning sound. Thereby, the administrator of the ion implantation apparatus 1 can know that an abnormality has occurred.

  Subsequently, the wafer transfer control unit 62 notifies the end station control unit 61 of an error (step S191). In response to this notification, the end station control unit 61 resets its own operation at an appropriate timing. Specifically, a CPU (central processing unit) that constitutes the end station control unit 61 is reset. Wafer transfer control unit 62 continues to issue an alarm until it detects a reset in end station control unit 61 (NO in step S192). Thereafter, when the wafer transfer control unit 62 detects reset (YES in step S192), the wafer transfer control unit 62 cancels the alarm (step S193) and ends the above processing. As a result, the operation of the wafer transfer mechanism 30 does not proceed any further.

  As described above, the wafer transfer control unit 62 detects by the slit detection sensor 38 when the pedestal Pi of the wafer holder 31 (or the pedestal Qi of the wafer holder 33) placed on the wafer carry-in / out side is positioned at the removal position. Based on the result, it can be determined whether or not the position of the slit hole 31 s matches a predetermined reference position (in the present embodiment, the position in the initial state). Thereby, it can be easily detected that the replacement of the processed wafer Wp with the unprocessed wafer Wu has failed. In addition, when the replacement fails, it is possible to reliably prevent the processed wafer Wp from being subjected to the ion implantation process again, thereby preventing the occurrence of defective products.

  For example, the pedestal detection sensors 37A and 37B may fail to detect the concavo-convex pattern due to deterioration of the concavo-convex pattern on the back surface of the pedestal through the ion implantation process or foreign matter adhering to the concavo-convex pattern. In such a case, the initialization of the rotation direction position of the wafer holder (step S181 in FIG. 6) fails or the rotation control of the wafer holder (step S184 in FIG. 6) fails. Although the replacement with the unprocessed wafer Wu fails, the slit holes 31 s and 33 s penetrating the wafer holders 31 and 33 are deteriorated to an indistinguishable level due to the influence of the ion implantation process, or are blocked due to adhesion of foreign matter. There is nothing to do. For this reason, the slit detection sensor 38 can reliably detect the slit holes 31s and 33s. Therefore, the wafer transfer control unit 62 can reliably detect failure in replacing the processed wafer Wp with the unprocessed wafer Wu.

  Furthermore, since the structure of the existing wafer holders 31 and 33 having the slit holes 31s and 33s for measuring the ion beam current can be used as they are, the sequence control process of the present embodiment can be realized at a low cost.

  As mentioned above, although embodiment of this invention was described with reference to drawings, these are illustrations of this invention and can also employ | adopt various forms other than the above. For example, the wafer holder 31 preferably has one slit hole 31s from the viewpoint that the ion beam current measurement slit hole 31s can be diverted as it is, but is not limited thereto, and the wafer holder 31 has two or more slits. You may have a hole. The same applies to the wafer holder 33.

  In addition to the slit hole 31s, a through hole or a notch through which light passes from the back surface side to the front surface side is formed in the wafer holder 31, and the wafer is conveyed so that the slit detection sensor 38 detects this through hole or notch. The configuration of the mechanism 30 may be changed. In this case, the through hole or notch is desirably formed in the vicinity of the peripheral portion of the wafer holder 31 between a pair of pedestals adjacent to each other so as to be clearly distinguished from the uneven pattern on the back surface of the pedestals P1 to P13. . The same applies to the wafer holder 33.

  Further, the present invention is not limited to the wafer transfer mechanism 30 of the ion implantation apparatus 1, and the configuration of the wafer transfer mechanism 30 of the present embodiment is applied to another batch type wafer processing apparatus (for example, a polishing apparatus). It is also possible to apply.

  DESCRIPTION OF SYMBOLS 1 Ion implantation apparatus (wafer processing apparatus), 20 Ion beam irradiation mechanism, 21 High voltage power supply, 22 Ion source, 24 Beam transport part, 25 Mass analyzer, 26 Beam shaping part, 30 Wafer conveyance mechanism, 31, 33 Wafer holder, 31s, 33s slit hole, P1-P13, Q1-Q13 pedestal (wafer mounting table), 32 holder drive unit, 34A, 34B exchange arm, 35A, 35B arm drive unit, 37A, 37B pedestal detection sensor, 38 slit detection sensor, 50 end station section, 51 holder support section, 52 holder drive section, 60 system controller, 61 end station control section, 62 wafer transfer control section, 63 operation panel, 64 light emitting section, 65 speaker.

Claims (13)

And has a plurality of pedestal, the wafer holder having a detected portion which is formed at a position corresponding to one of the plurality of pedestal,
A wafer processing mechanism for processing a plurality of wafers respectively mounted on the mounting surfaces of the plurality of pedestals;
After the processing, the wafer holder is rotated to sequentially position the plurality of pedestals at a predetermined removal position, the wafer is removed from the positioned pedestals, and then an unprocessed wafer is mounted on the pedestals. A wafer transfer mechanism to be placed;
A wafer transfer control unit for controlling the operation of the wafer transfer mechanism;
A pedestal detection sensor for detecting the pedestal of the wafer holder rotated by the wafer transfer mechanism based on a pattern provided on the back surface of the pedestal which is the surface opposite to the placement surface;
When any of said plurality of pedestal is positioned at the detachment position, the position of the detected portion, and outputs a determination signal indicating whether or not to match the predetermined reference position to the wafer transport controller A detected part detection sensor;
Equipped with a,
The wafer transfer control unit increments a variable by 1 from a predetermined initial value every time the pedestal detection sensor detects the pedestal, and determines that the variable is equal to the total number of the plurality of pedestals included in the wafer holder. wafer processing apparatus in case of, wherein also be output from the alarm signal when the position of the detected part on the basis of the determination signal is determined not to match the reference position. The wafer processing apparatus according to claim 1, wherein the wafer transfer control unit returns the variable to the initial value after determining that the variable is equal to a total number of the plurality of pedestals included in the wafer holder. . 3. The wafer processing apparatus according to claim 1, wherein the detected portion is formed in a region between a pair of pedestals adjacent to each other among the plurality of pedestals. The wafer processing apparatus according to claim 3 ,
The detected part is a through hole,
The wafer processing mechanism is an ion implantation mechanism that irradiates an ion beam to a plurality of wafers respectively mounted on the plurality of pedestals,
The through hole is a slit hole through which the ion beam passes.
A wafer processing apparatus. The wafer processing apparatus according to any one of claims 1 to 4 , wherein
Before SL wafer transfer mechanism, the wafer processing apparatus characterized by sequentially positioning a plurality of pedestal to the detaching position by using the detection result of the pedestal detection sensor. A wafer processing apparatus according to any one of claims 1 to 5 ,
The plurality of pedestals are arranged in a ring around the rotation axis of the wafer holder,
The detected portion is formed in a region between a pair of adjacent pedestals among the plurality of pedestals.   The wafer processing apparatus according to claim 6, further comprising an alarm output unit that outputs visual information or acoustic information in response to the alarm signal. A plurality of pedestal which a plurality of wafers are mounted on the mounting surface respectively, by using a wafer holder having a detected portion which is formed at a position corresponding to one of the plurality of pedestal, said plurality A process for processing the wafer;
After the processing, the wafer holder is rotated to sequentially position the plurality of pedestals at a predetermined removal position, and after removing the wafer from the positioned pedestals, an unprocessed wafer is placed on the pedestal. A process of
In the step of placing the unprocessed wafer, the pedestal of the rotating wafer holder is pedestal detected using a pedestal detection sensor based on a pattern provided on the back surface of the pedestal that is the surface opposite to the placement surface. Detecting step;
Determining whether or not the position of the detected portion matches a predetermined reference position using a detected portion detection sensor when any of the plurality of pedestals is positioned at the removal position; ,
Equipped with a,
When it is determined that the variable incremented by one from a predetermined initial value every time the pedestal is detected by the pedestal detection sensor is equal to the total number of the plurality of pedestals included in the wafer holder, based on the determination signal wafer processing method according to claim Rukoto alarm signal is output when the position of the detected portion is determined not to match the reference position. The wafer processing method according to claim 8, wherein the variable returns to the initial value after it is determined that the variable is equal to a total number of the plurality of pedestals included in the wafer holder. A wafer processing method according to claim 8 or 9, wherein the detected portion is a wafer processing method characterized in that it is formed in a region between a pair of pedestal adjacent to each other among the plurality of pedestal. The wafer processing method according to claim 10 , comprising:
The detected part is a through hole,
The process is an ion implantation process for irradiating the plurality of wafers with an ion beam,
The wafer processing method, wherein the through hole is a slit hole through which the ion beam passes. A wafer processing method according to any one of claims 8 11, wherein the plurality of pedestal is the detachment position by using the detection result of the pedestal detecting sensor for detecting the position of said pedestal A wafer processing method characterized by being sequentially positioned. The method of manufacturing a semiconductor device comprising the steps of wafer processing method according to claim 8 in any one of the 12.

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