Wafer Processing Equipment

Abstract

To provide a wafer processing device that eliminates the need to transfer a wafer between a robot arm and an aligner while transferring the wafer from a storage place to a processing position.SOLUTION: A robot arm holds and transfers a wafer which is provided with a mark that identifies its rotational position, from the storage place to the processing position. Positional information of the mark of the wafer held by the robot arm is acquired in the middle of a path along which the robot arm transfers the wafer from the storage place to the processing position.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present invention relates to a wafer processing apparatus. [Background technology]

[0002] There is known a wafer processing apparatus that uses a robot arm to transfer a semiconductor wafer onto a stage in a processing chamber and processes the wafer (see Patent Document 1). The semiconductor wafer is provided with marks such as an orientation flat and a notch for identifying the crystal orientation of the wafer. The robot arm takes the wafer from a storage location and temporarily transfers it to an aligner. After the aligner has determined the position of the wafer in the rotational direction, the robot arm takes the wafer from the aligner and transfers it onto a stage in the processing chamber. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2020-77758 A Summary of the Invention [Problem to be solved by the invention]

[0004] In the wafer processing apparatus disclosed in Patent Document 1, the wafer must be transferred between the robot arm and the aligner during the transfer from the wafer storage location to the processing chamber. Even if the aligner positions the wafer in the rotational direction, the wafer may be misaligned when it is returned from the aligner to the robot arm. In addition, the wafer may be damaged during the transfer.

[0005] SUMMARY OF THE PRESENT EMBODIMENT An object of the present invention is to provide a wafer processing apparatus that does not require the transfer of the wafer between a robot arm and an aligner during the transfer of the wafer from a storage location to a processing location. [Means for solving the problem]

[0006] According to one aspect of the present invention, a robot arm that holds a wafer having a mark for identifying a position in a rotational direction and transfers the wafer from a storage location to a processing location; a stage provided at the processing position for transferring the wafer between the stage and the robot arm; a position information acquirer that acquires position information of a mark of a wafer held by the robot arm along a path along which the robot arm transfers the wafer from the storage location to the processing location; 、 a control device that detects the orientation of the wafer held by the robot arm in a rotational direction based on the position information of the mark acquired by the position information acquirer, and after transferring the wafer to the stage, controls the stage based on the detection result to align the wafer in the rotational direction; A wafer processing apparatus comprising: Effect of the Invention

[0007] Since the position information of the wafer marks is acquired while the wafer is held by the robot arm, there is no need to transfer the wafer in order to acquire the position information of the wafer marks. [Brief description of the drawings]

[0008] [Figure 1] FIG. 1 is a schematic plan view of a wafer processing apparatus according to one embodiment. [Diagram 2] FIG. 2 is a schematic cross-sectional view taken along dashed line 2-2 of FIG. [Diagram 3] FIG. 3 is a flow chart showing a procedure of wafer processing by the wafer processing apparatus according to one embodiment. [Figure 4] FIG. 4 is a flow chart showing a procedure of wafer processing by the wafer processing apparatus according to another embodiment. [Diagram 5] FIG. 5 is a schematic plan view showing a state after the wafer held by the robot arm has passed through the transfer entrance in the embodiment shown in FIG. [Figure 6] FIG. 6 is a schematic plan view of a wafer processing apparatus according to still another embodiment. [Figure 7] FIG. 7 is a plan view of a stage of a wafer processing apparatus according to still another embodiment. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0009] A wafer processing apparatus according to one embodiment of the present invention will be described with reference to FIGS. 1 to 3. FIG. 1 is a schematic plan view of a wafer processing apparatus according to one embodiment. The wafer processing apparatus according to this embodiment has a robot chamber 10 and a processing chamber 30. The internal space of the robot chamber 10 and the internal space of the processing chamber 30 are connected via an openable / closable loading / unloading entrance 40.

[0010] A robot arm 11 is disposed in a robot chamber 10. A storage location 15 for storing wafers 50 is also provided in the robot chamber 10. For example, a wafer cassette containing a plurality of wafers 50 is disposed in the storage location 15. Unprocessed wafers 50 are stored in one storage location 15, and processed wafers 50 are stored in the other storage location 15. A mark 51 is provided on the wafer 50 to identify the position (crystal axis orientation) of the wafer 50 in the rotational direction. For example, an orientation flat, a notch, or the like is used as the mark 51.

[0011] The robot arm 11 is rotatable about its base and is extendable and retractable. The robot arm 11 includes, for example, a first link 11A attached to the base, a second link 11B connected to the tip of the first link 11A via a joint, and a robot hand 11C attached to the tip of the second link 11B via a joint. In Fig. 1, the robot arm 11 shown by solid lines shows, for example, a standard posture, and the robot arm 11 shown by dashed lines shows a state in which the robot hand 11C at the tip has passed through the transfer entrance 40 and entered the processing chamber 30.

[0012] A stage 31 is disposed within a processing chamber 30. The stage 31 is provided with a plurality of lift pins 33 that can be raised and lowered. With the lift pins 33 raised, the wafer 50 is transferred between the lift pins 33 and the robot arm 11. The lift pins 33 are lowered to vacuum-suck the wafer 50, thereby fixing the wafer 50 to the stage 31. Processing is performed on the wafer 50 while it is held on the stage 31. The position at which the wafer 50 is held by the stage 31 is referred to as the processing position 32 of the wafer 50.

[0013] The robot arm 11 places the wafer 50 on the robot hand 11C and transfers the wafer 50 between the storage location 15 and the processing position 32. When the wafer 50 is to be loaded into the processing chamber 30 or when the wafer 50 is to be unloaded from the processing chamber 30, the loading / unloading entrance 40 is opened.

[0014] A line sensor 21 is provided along the loading / unloading entrance 40. The line sensor 21 scans the wafer 50 when the wafer 50 passes through the loading / unloading entrance 40. The scan result by the line sensor 21 is input to the control device 20 as image data. This image data includes a mark 51 provided on the wafer 50 and contains position information of the mark 51. In other words, the line sensor 21 functions as a position information acquirer that acquires the position information of the mark 51 provided on the wafer 50.

[0015] The control device 20 controls the operation of the robot arm 11, the opening and closing of the loading / unloading entrance 40, the scanning operation of the line sensor 21, and the raising and lowering operation of the lift pins 33 of the stage 31. Furthermore, the control device 20 detects the relative center position of the wafer 50 with respect to the robot hand 11C and the position of the mark 51 in the rotational direction by analyzing image data acquired from the line sensor 21.

[0016] Fig. 2 is a schematic cross-sectional view taken along dashed line 2-2 in Fig. 1. The internal space of the robot chamber 10 and the internal space of the processing chamber 30 are connected to each other via a loading / unloading entrance 40. A line sensor 21 is attached to the upper edge of the loading / unloading entrance 40.

[0017] A stage 31 disposed in the processing chamber 30 is supported on the bottom surface of the processing chamber 30 by a moving mechanism 35 and a rotating mechanism 36. The moving mechanism 35 includes an X-direction moving mechanism 35X and a Y-direction moving mechanism 35Y. The X-direction moving mechanism 35X and the Y-direction moving mechanism 35Y move the rotating mechanism 36 in the x-direction and y-direction that are orthogonal to each other in a horizontal plane, respectively. The rotating mechanism 36 rotates the stage 31 in the horizontal plane. A wafer 50 to be processed is held on the stage 31. FIG. 2 shows a state in which the lift pins 33 are lowered and the wafer 50 is adsorbed to the stage 31.

[0018] A laser transmission window 38 is attached to the ceiling of the processing chamber 30. A laser beam output from the laser optical system 25 passes through the laser transmission window 38 and is incident on the wafer 50 on the stage 31. In Fig. 2, the path of the laser beam is shown diagrammatically by a hollow arrow. When the laser beam is incident on the wafer 50, a process such as activation annealing is performed.

[0019] The tip of the robot arm 11 enters the processing chamber 30 through the loading / unloading entrance 40, whereby the wafer 50 is transferred between the stage 31 and the robot arm 11. In FIG. 2, the loading direction of the wafer 50 is indicated by a solid arrow. When the wafer 50 passes through the loading / unloading entrance 40, image data is acquired by the line sensor 21. The acquired image data is input to the control device 20. The control device 20 controls the moving mechanism 35 and the rotating mechanism 36.

[0020] 3 is a flow chart showing the procedure of wafer processing by the wafer processing apparatus according to this embodiment. The procedure shown in FIG. 3 is executed by the controller 20 controlling the robot arm 11, the lift pins 33 of the stage 31, and the rotation mechanism 36.

[0021] First, the robot arm 11 takes out an unprocessed wafer 50 from the storage location 15 (FIG. 1) (step SA1). After the wafer 50 is taken out from the storage location 15, the transfer of the wafer 50 begins (step SA2). During the transfer of the wafer 50, the control device 20 acquires position information of a mark 51 that identifies the position of the wafer 50 in the rotational direction (step SA3). Specifically, the control device 20 controls the line sensor 21 to scan the wafer 50 and acquires image data that is the scan result.

[0022] When the control device 20 acquires the image data from the line sensor 21, it performs image analysis to detect the center position of the wafer 50 relative to the robot hand 11C and the position in the rotational direction of the mark 51. In parallel with this detection process, the wafer 50 is handed over from the robot arm 11 to the stage 31 (step SA4). At this time, the wafer 50 is aligned with the stage 31 in the horizontal direction.

[0023] Thereafter, the control device 20 controls the rotation mechanism 36 (FIG. 2) to align the wafer 50 in the rotational direction (step SA5). This alignment is performed based on the detection result of the position of the mark 51 in the rotational direction obtained by analyzing the image data.

[0024] After the horizontal and rotational alignment of the wafer 50 is completed, a laser beam is applied to the wafer 50 to perform an annealing process (step SA6). When the annealing process is completed, the robot arm 11 picks up the processed wafer 50 from the stage 31 and transfers it to the storage location 15 for processed wafers (step SA7).

[0025] Next, the excellent effects of the above embodiment will be described. In the above embodiment, while the wafer 50 is being transferred from the storage location 15 to the processing location 32, position information of the mark 51 of the wafer 50 is acquired while the wafer is held by the robot arm 11. Since there is no need to transfer the wafer 50 between the robot arm 11 and an aligner or the like for acquiring the position information of the mark 51, positional deviation that may occur during transfer of the wafer 50 between the robot arm 11 and the aligner or the like is prevented. In addition, since there is no need to install an aligner or the like for the robot arm 11 to transfer the wafer 50, the device can be made more compact. In addition, since the number of times the wafer 50 is transferred is reduced, damage to the wafer 50 during transfer can be suppressed.

[0026] Next, a wafer processing apparatus according to a modification of the above embodiment will be described. The wafer processing apparatus according to the above embodiment is used for activation annealing of the wafer 50, but can also be used for other laser annealing. For example, it can also be used for crystallization annealing of an amorphous semiconductor film. Also, in the above embodiment, the wafer 50 is a semiconductor wafer, but the wafer 50 does not have to be a semiconductor wafer. For example, it can be an insulating wafer such as a glass substrate or a sapphire substrate.

[0027] In the above embodiment, the line sensor 21 is attached along the loading / unloading entrance 40, but it may be attached at another position. For example, the line sensor 21 may be attached so that the path along which the wafer 50 passes when the wafer 50 is removed from the storage location 15 for unprocessed wafers 50 is perpendicular to the arrangement direction of the multiple sensors of the line sensor 21 in a plan view.

[0028] In the wafer processing apparatus according to the above embodiment, the wafer 50 is aligned in the rotational direction based on the position information of the mark 51 obtained while the wafer 50 is held by the robot arm 11, but it is not necessary to rotate the wafer 50 to align it. The wafer 50 may be processed without rotating the wafer 50 by using the position information of the mark 51 obtained while the wafer 50 is held by the robot arm 11.

[0029] Next, a wafer processing apparatus according to another embodiment will be described with reference to Figures 4 and 5. Hereinafter, a description of the configuration common to the wafer processing apparatus according to the embodiment shown in Figures 1 to 3 will be omitted.

[0030] Fig. 4 is a flow chart showing the procedure of wafer processing by the wafer processing apparatus according to this embodiment. The procedure from step SA1 to step SA3 is the same as that performed by the wafer processing apparatus according to the embodiment shown in Fig. 3. In the embodiment shown in Fig. 3, after the wafer 50 is delivered to the stage 31 (step SA4), the stage 31 is rotated to align the wafer 50 in the rotational direction (step SA5). In contrast, in this embodiment, the attitude of the robot arm 11 is controlled to align the wafer 50 in the rotational direction, and the wafer 50 is delivered from the robot arm 11 to the stage 31 after the alignment is completed (step SB1).

[0031] The procedures of steps SA6 and SA7 thereafter are the same as those performed in the wafer processing apparatus according to the embodiment shown in FIG.

[0032] 5 is a schematic plan view showing the state after the wafer 50 held by the robot arm 11 has passed through the loading / unloading entrance 40. When the entire wafer 50 has passed through the loading / unloading entrance 40, the control device 20 acquires position information of the mark 51 provided on the wafer 50 from the line sensor 21 and detects the position of the wafer 50 in the rotational direction. The control device 20 adjusts the position of the wafer 50 held by the robot arm 11 in the rotational direction by controlling the attitude of the robot arm 11.

[0033] 1, when the wafer 50 is transferred from the robot arm 11 to the stage 31, the joint connecting the second link 11B and the robot hand 11C is located on a line connecting the rotation center of the base of the robot arm 11 and the geometric center of the stage 31 in a plan view. In contrast, in the embodiment shown in Fig. 5, the joint connecting the second link 11B and the robot hand 11C is shifted from the line L connecting the rotation center of the base of the robot arm 11 and the geometric center of the stage 31, thereby aligning the wafer 50 in the rotational direction.

[0034] Next, the excellent effects of this embodiment will be described. 1 to 3, in this embodiment, it is possible to obtain the effects of preventing misalignment that may occur when transferring the wafer 50 between the robot arm 11 and an aligner or the like, miniaturizing the device, and suppressing damage to the wafer 50. Furthermore, in this embodiment, it is not necessary to rotate the stage 31 to align the wafer 50 in the rotational direction. Therefore, it is not necessary to provide a rotation mechanism 36 (FIG. 2) for rotating the stage 31. Furthermore, in this embodiment, it is not necessary to align the wafer 50 in the rotational direction after transferring the wafer 50 to the stage 31, so it is possible to improve throughput.

[0035] Next, a wafer processing apparatus according to still another embodiment will be described with reference to Fig. 6. Below, a description of the configuration common to the wafer processing apparatus according to the embodiment shown in Figs.

[0036] 6 is a schematic plan view of the wafer processing apparatus according to this embodiment. In the embodiment shown in FIG. 1, a line sensor 21 is used as a position information acquirer for acquiring position information of the mark 51 of the wafer 50. In contrast, in this embodiment, an imaging device 22 for acquiring two-dimensional image data is used as the position information acquirer. The imaging device 22 captures an image of the wafer 50 held by the robot arm 11 along the path along which the robot arm 11 transfers the wafer 50 from the storage location 15 to the processing location 32, and generates two-dimensional image data. The two-dimensional image data generated by the imaging device 22 is input to the control device 20. For example, when the robot arm 11 takes out the wafer 50 from the storage location 15 for the unprocessed wafer 50, the wafer 50 is placed within the angle of view of the imaging device 22.

[0037] The control device 20 detects the position of the mark 51 on the wafer 50 in the rotational direction by analyzing the two-dimensional image data acquired from the imaging device 22 .

[0038] Next, the excellent effects of this embodiment will be described. In this embodiment, as in the embodiment shown in Figures 1 to 3, it is possible to obtain the effects of preventing positional deviation that may occur when transferring the wafer 50 between the robot arm 11 and an aligner or the like, miniaturizing the device, and suppressing damage to the wafer 50.

[0039] Next, a wafer processing apparatus according to still another embodiment will be described with reference to Fig. 7. Hereinafter, a description of the configuration common to the wafer processing apparatus according to the embodiment shown in Figs.

[0040] Fig. 7 is a plan view of stage 31 of the wafer processing apparatus according to this embodiment. In the embodiment shown in Fig. 2, stage 31 is rotated by rotation mechanism 36, thereby rotating wafer 50 held on stage 31. In contrast, in the embodiment shown in Fig. 7, multiple lift pins 33 are supported by rotation mechanism 34, and multiple lift pins 33 revolve around the geometric center of stage 31 by rotation mechanism 34.

[0041] The wafer 50 is held in a raised state by the lift pins 33 and the lift pins 33 are caused to revolve, whereby the wafer 50 can be aligned in the rotational direction.

[0042] Next, the excellent effects of this embodiment will be described. 1 to 3, this embodiment also provides the effects of preventing misalignment that may occur when transferring the wafer 50 between the robot arm 11 and an aligner or the like, miniaturizing the device, and suppressing damage to the wafer 50. Furthermore, in this embodiment, the lowering operation of the lift pins 33 and the revolution of the lift pins 33 by the rotation mechanism 34 can be performed in parallel. Therefore, the time required for aligning and holding the wafer 50 in the rotational direction can be shortened.

[0043] The above-mentioned embodiments are merely examples, and it goes without saying that partial replacement or combination of the configurations shown in different embodiments is possible. Similar effects due to similar configurations of multiple embodiments are not mentioned in each embodiment. Furthermore, the present invention is not limited to the above-mentioned embodiments. For example, it will be obvious to those skilled in the art that various modifications, improvements, combinations, etc. are possible. [Explanation of symbols]

[0044] 10 Robot Room 11 Robot Arm 11A Link 1 11B 2nd link 11C Robot Hand 15 Wafer storage area 20 Control device 21 Line sensor 22 Imaging device 25 Laser Optical System 30 Processing Room 31 Stage 32 Wafer Processing Position 33 Lift pin 34 Rotation mechanism 35 Moving mechanism 35X x direction movement mechanism 35Y y-direction movement mechanism 36 Rotation mechanism 38 Laser transmission window 40 Loading / unloading entrance 50 wafers 51 Mark on wafer

Claims

1. a robot arm that holds a wafer having a mark for identifying a position in a rotational direction and transfers the wafer from a storage location to a processing location; a stage provided at the processing position for transferring the wafer between the stage and the robot arm; a position information acquirer that acquires position information of a mark of a wafer held by the robot arm along a path along which the robot arm transfers the wafer from the storage location to the processing location; a control device that detects the orientation of the wafer held by the robot arm in a rotational direction based on the position information of the mark acquired by the position information acquirer, and after transferring the wafer to the stage, controls the stage based on the detection result to align the wafer in the rotational direction; A wafer processing apparatus comprising:

2. a processing chamber including the processing position therein and having a loading / unloading port for loading and unloading a wafer held by the robot arm; The wafer processing apparatus according to claim 1 , wherein the position information acquisition device includes a line sensor that acquires an image of the wafer passing through the transfer entrance.

3. The wafer processing apparatus according to claim 1 , wherein the position information acquirer includes an imaging device that acquires a two-dimensional image of the wafer held by the robot arm.

Images