JP7779680B2 - Aligner and method for correcting positional deviation of plate-shaped workpiece - Google Patents

Description

The present invention relates to an aligner device and a method for correcting positional deviation of a plate-shaped workpiece. More specifically, it relates to technology that detects the amount of positional deviation of a plate-shaped workpiece, such as a semiconductor wafer, from a reference position and corrects the position of the plate-shaped workpiece based on the detected amount of positional deviation.

In semiconductor processing, for example, a wafer loaded into a load lock chamber is transferred into a processing chamber by a transfer robot. Depending on the processing to be performed in the processing chamber, the wafer must be accurately transferred to a reference position within the processing chamber. To achieve this, an aligner device, such as that shown in Patent Document 1, is used before the workpiece is transferred into the processing chamber. This aligner device is configured to detect the amount of misalignment of the wafer in the planar direction (X-Y directions) and rotational direction (θ direction). Specifically, a line sensor detects the outer periphery of a circular wafer while it is rotating, and then detects the amount of misalignment of the wafer in the X-Y and θ directions based on the detection data. The aligner device uses this misalignment information to correct the misalignment in the X-Y and θ directions. The transfer robot then picks up the corrected wafer from the aligner device and transports it to the reference position within the processing chamber for the next process, for example.

The process of correcting wafer misalignment using the conventional aligner device described above is performed after the wafer is transferred from the transfer robot to the aligner device. After the misalignment correction, the wafer is then transferred back to the transfer robot, which then transports it to the next process. However, this type of wafer misalignment correction process requires repeated transfers of the wafer between the transfer robot and the aligner device, lengthening the wafer transport time, including the misalignment correction process.

Japanese Patent Application Laid-Open No. 2015-195328

The present invention was conceived in light of the above circumstances, and its main objective is to provide an aligner device that is configured to shorten the transport time, including the process of correcting positional deviations of plate-shaped workpieces.

To solve the above problems, the present invention employs the following technical means.

The aligner device provided by a first aspect of the present invention is characterized by comprising: a robot hand having a hand body on which a plate-shaped workpiece can be placed and held; a sensor having a downward-facing sensor surface capable of detecting the outer shape of a plate-shaped workpiece that is close to or in contact with the lower part of the sensor surface; a work lift mechanism that is transported by the robot hand and can lift the plate-shaped workpiece placed on the hand body so that it is close to or in contact with the sensor surface and can then lower it from the lifted state; and a positional deviation calculation means that calculates the amount of positional deviation of the plate-shaped workpiece from a reference position based on the outer shape of the plate-shaped workpiece in a state lifted by the work lift mechanism, obtained by the sensor.

In a preferred embodiment, the system further includes a control means for controlling the robot hand so that, when the work lift mechanism lifts the plate-shaped workpiece and transfers it onto the hand body, the plate-shaped workpiece is placed at a reference position on the hand body based on the positional deviation amount calculated by the positional deviation amount calculation means.

In a preferred embodiment, the device includes a function to output the amount of positional deviation calculated by the positional deviation calculation means to an external device.

In a preferred embodiment, the plate-shaped workpiece is a semiconductor wafer.

A method for correcting positional deviation of a plate-shaped workpiece provided by a second aspect of the present invention includes a robot hand having a hand body on which a plate-shaped workpiece can be placed and held; a sensor having a downward-facing sensor surface capable of detecting the outer shape of a plate-shaped workpiece that is in proximity to or in contact with the lower part of the sensor surface; a work lift mechanism that is transported by the robot hand and that can lift the plate-shaped workpiece placed on the hand body so that it is in proximity to or in contact with the sensor surface and then lower it from the lifted state; a positional deviation amount calculation means that calculates the amount of deviation of the plate-shaped workpiece from a reference position based on the outer shape of the plate-shaped workpiece in a state lifted by the work lift mechanism acquired by the sensor; and when the work lift mechanism lifts the plate-shaped workpiece and transfers it onto the hand body, the robot hand is moved so that the plate-shaped workpiece is placed at the reference position on the hand body based on the positional deviation amount calculated by the positional deviation amount calculation means. A method for correcting positional deviation of a plate-shaped workpiece using an aligner device having a control means for controlling a position of the plate-shaped workpiece placed on the hand body, the method comprising: a plate-shaped workpiece carrying-in step of moving the robot hand so that the plate-shaped workpiece placed on the hand body is positioned at a correction reference position below the sensor; an outer shape acquisition step of lifting the plate-shaped workpiece from the hand body using the work lift mechanism and bringing it close to or into contact with the sensor surface of the sensor, and acquiring the outer shape of the plate-shaped workpiece using the sensor; a position deviation calculation step of calculating the amount of position deviation of the plate-shaped workpiece in the X and Y directions from a reference position based on the amount of position deviation calculated by the position deviation calculation means when the work lift mechanism lifts the plate-shaped workpiece and transfers it onto the hand body, and controls the robot hand in the X and Y directions so that the plate-shaped workpiece is placed at the reference position on the hand body.

In a preferred embodiment, the position correction step is performed by controlling the first robot hand used in the plate-shaped workpiece carrying-in step.

In a preferred embodiment, the position correction step is performed by controlling a second robot hand that has a hand body capable of placing and holding the plate-shaped workpiece, different from the first robot hand used in the plate-shaped workpiece carrying-in step.

In a preferred embodiment, the plate-shaped workpiece is a semiconductor wafer.

The aligner device configured as described above can shorten the transport time, including the process of correcting misalignment of plate-shaped workpieces.

Other features and advantages of the present invention will become more apparent from the following detailed description taken in conjunction with the accompanying drawings.

1 is a schematic plan view of an aligner device according to a first embodiment of the present invention. FIG. 1 is a schematic side view of an aligner device according to a first embodiment of the present invention. FIG. 1 is a block diagram showing a configuration of an aligner device according to the present invention. 2A and 2B are explanatory views of an operating state of the aligner device according to the first embodiment of the present invention, where FIG. 2A is an explanatory view seen from the direction of an arrow Y in FIG. 1 , and FIG. 2B is an explanatory view seen from the direction of an arrow X in FIG. 1 . 2A and 2B are explanatory views of an operating state of the aligner device according to the first embodiment of the present invention, where FIG. 2A is an explanatory view seen from the direction of an arrow Y in FIG. 1 , and FIG. 2B is an explanatory view seen from the direction of an arrow X in FIG. 1 . 1 is a diagram illustrating the operation of the aligner device according to the present invention. 2A and 2B are explanatory views of an operating state of the aligner device according to the first embodiment of the present invention, where FIG. 2A is an explanatory view seen from the direction of an arrow Y in FIG. 1 , and FIG. 2B is an explanatory view seen from the direction of an arrow X in FIG. 1 . 2A and 2B are explanatory views of an operating state of the aligner device according to the first embodiment of the present invention, where FIG. 2A is an explanatory view seen from the direction of an arrow Y in FIG. 1 , and FIG. 2B is an explanatory view seen from the direction of an arrow X in FIG. 1 . FIG. 10 is a schematic plan view of an aligner device according to a second embodiment of the present invention. FIG. 10 is a schematic side view of an aligner device according to a second embodiment of the present invention. 10A and 10B are explanatory views of an operating state of an aligner device according to a second embodiment of the present invention, where FIG. 10A is an explanatory view seen from the direction of an arrow Y in FIG. 9 and FIG. 10B is an explanatory view seen from the direction of an arrow X in FIG. 9 . 10A and 10B are explanatory views of an operating state of an aligner device according to a second embodiment of the present invention, where FIG. 10A is an explanatory view seen from the direction of an arrow Y in FIG. 9 and FIG. 10B is an explanatory view seen from the direction of an arrow X in FIG. 9 . 10A and 10B are explanatory views of an operating state of an aligner device according to a second embodiment of the present invention, where FIG. 10A is an explanatory view seen from the direction of an arrow Y in FIG. 9 and FIG. 10B is an explanatory view seen from the direction of an arrow X in FIG. 9 . 10A and 10B are explanatory views of an operating state of an aligner device according to a second embodiment of the present invention, where FIG. 10A is an explanatory view seen from the direction of an arrow Y in FIG. 9 and FIG. 10B is an explanatory view seen from the direction of an arrow X in FIG. 9 . 10A and 10B are explanatory views of an operating state of an aligner device according to a second embodiment of the present invention, where FIG. 10A is an explanatory view seen from the direction of an arrow Y in FIG. 9 and FIG. 10B is an explanatory view seen from the direction of an arrow X in FIG. 9 . 10A and 10B are explanatory views of an operating state of an aligner device according to a second embodiment of the present invention, where FIG. 10A is an explanatory view seen from the direction of an arrow Y in FIG. 9 and FIG. 10B is an explanatory view seen from the direction of an arrow X in FIG. 9 .

Below, preferred embodiments of the present invention will be described in detail with reference to the drawings.

Figures 1 to 10 show an aligner device B1 according to a first embodiment of the present invention.

As shown in Figures 1 to 3, the aligner device B1 includes a workpiece misalignment detection device A1, which operates in cooperation with the robot hand 1 and includes a sensor 3, a workpiece lift mechanism 5, and a misalignment calculation means 6 that calculates the amount of misalignment of the workpiece relative to a reference position based on workpiece outer edge shape information from the sensor 3.

The robot hand 1 has a structure in which a hand body 13 is attached to a support 12 mounted on, for example, the end arm (not shown) of an articulated robot. The hand body 13 is capable of holding a semiconductor wafer W as a workpiece on its upper surface. The robot hand 1 has the function of moving the hand body 13 in a planar direction (X-Y directions) while at least maintaining a horizontal position under the control of a manipulator (not shown). In this embodiment, the planar shape of the hand body 13 is a two-pronged fork shape as shown in Figure 1, but it may have other shapes, such as a three-pronged fork shape.

The sensor 3 employed has the ability to capture an image of the outline of a planar object located below it through contact or non-contact proximity. The sensor 3 is attached with its sensor surface 31 facing downward to the underside of a support plate 41 extending horizontally from the frame 4. Examples of such sensors 3 include those that utilize electrostatic technology to recognize the presence of an object, as used in touch panels, or those that employ a planar array of multiple image sensors such as CCDs. In the present invention, as described below, the sensor 3 is required to recognize the outline of the semiconductor wafer W. Therefore, it is sufficient for the sensor 3 to have a planar shape sufficient to recognize the outline of the semiconductor wafer W within the range of possible misalignment in the X-Y directions. In other words, the sensor 3 may be circular, as shown in Figure 6, or may have other shapes, such as a rectangle or a doughnut shape.

The work lift mechanism 5 functions to lift or lower the semiconductor wafer W held by the robot hand 1 and inserted into the frame 4 by a certain height from the hand body 13. In this embodiment, three stays 51 are positioned so as not to interfere with the path of entry of the semiconductor wafer W into the frame 4. An inward-facing horizontal portion 511 is formed at the lower end of each stay (see FIG. 1), and upward-protruding lift pins 512 are provided on the horizontal portion 511 (see FIG. 2). Each set of three stays 51 and three lift pins 512 is provided corresponding to a sensor 3, and each set is actuated a predetermined distance vertically by an actuator (not shown), such as an air cylinder, located outside the frame 4. The number of sets of three stays 51 and three lift pins 512 provided corresponding to each sensor 3 is not limited to this number. For example, as shown in FIG. 9, which will be described later, a set of four stays and four lift pins may be provided.

As shown in Figures 1 and 6, a semiconductor wafer W is typically circular and plate-shaped, with a notch W1 or a cutout (not shown) called an orientation flat formed on its outer periphery for detecting its circumferential rotational orientation. In semiconductor processing, such a semiconductor wafer W is loaded into a processing chamber and subjected to a specific process. Depending on the process, however, the semiconductor wafer W may need to be accurately positioned at reference positions in the X-Y and θ directions. In such cases, the present invention enables positional misalignment to be corrected before the robot hand 1 loads the semiconductor wafer W into the processing chamber.

The misalignment calculation means 6 calculates the misalignment amounts in the X-Y and θ directions of the semiconductor wafer W from a reference position based on the outer shape of the semiconductor wafer W captured as an image by the sensor 3. Specifically, as shown in FIG. 6, it calculates the misalignment amount δx in the X direction and the misalignment amount δy in the Y direction of the center of the image of the semiconductor wafer W, for example, the center O1 of the outer circle in image W' of the semiconductor wafer, from reference position C1 where the center of the semiconductor wafer W should be located, and it also calculates the misalignment amount δθ in the θ direction of the notch W1 in image W' from reference position N1 where the notch W1 of the semiconductor wafer W should be located.

The workpiece positional deviation detection device A1 configured as described above cooperates with the robot hand 1 and workpiece lift mechanism 5, which are driven and controlled by the control device 7, to form the aligner device B1, which operates, for example, as follows:

As shown in FIG. 4, each lift pin 512 is in a downward movement position, and the robot hand 1, with the semiconductor wafer W placed and held on the hand body 13, moves, for example, in the X direction, until the hand body 13 advances to the correction reference position within the frame body 4 and positions the semiconductor wafer W below the sensor 3. At this time, the semiconductor wafer W has been transferred from a multi-stage cassette (not shown) or load lock chamber (not shown), and is misaligned in the X-Y and θ directions relative to the reference position C1 where the semiconductor wafer W on the hand body 13 should be located.

Next, as shown in FIG. 5, the lift pins 512 rise to lift the semiconductor wafer W from the hand body 13 and bring it close to the underside of the sensor 3. Here, to avoid contamination of the surface of the semiconductor wafer W, the semiconductor wafer W does not come into contact with the sensor 3. In this state, the sensor 3 acquires the outer shape of the semiconductor wafer W as image data, as described above. The positional deviation calculation means 6 receives this image data and calculates the positional deviation δx in the X direction, the positional deviation δy in the Y direction, and the positional deviation δθ in the θ direction for the semiconductor wafer W from the reference positions C1 and N1, as described above (FIG. 6).

Next, the semiconductor wafer W is transferred to the hand body 13 while correcting the positional deviation δx in the X direction and the positional deviation δy in the Y direction as follows:

As shown in FIG. 7, in order for the hand body 13 to correct the positional deviations δx and δy of the semiconductor wafer W, the movement of the robot hand 1 is controlled so that the hand body 13 moves δxa and δya from the correction reference position. In this state, as shown in FIG. 8, the set of lift pins 512 is moved downward, and the semiconductor wafer W held up by the lift pins 512 is transferred to the hand body 13. In this state, the semiconductor wafer W placed on the hand body 13 is positioned at its reference position C1 relative to the hand body 13. In this way, the hand body 13 can perform the above operations without retracting from the frame 4.

The robot hand 1 then retracts from the frame 4 with the semiconductor wafer W placed and held at the reference position C1 in the X-Y direction of the hand body 13, and can transport the semiconductor wafer W to the next specified process.

As described above, with the workpiece misalignment detection device A1 configured as described above and the aligner device B1 including it, the outer shape of the semiconductor wafer W as a plate-like workpiece can be acquired by the sensor 3 having the planar sensor surface 31, and the X-direction misalignment amount δx, Y-direction misalignment amount δy, and θ-direction misalignment amount δθ from the reference position of the semiconductor wafer W can be calculated from the image of the outer shape thus acquired. Therefore, the physical configuration for detecting the misalignment amount of the semiconductor wafer W can be configured to be thin.

The aligner device B1 comprises a sensor 3, a workpiece lift mechanism 5, a misalignment calculation means 6, and a control device 7. The sensor 3 has a downward-facing sensor surface 31. The workpiece lift mechanism 5 can lift a semiconductor wafer W (plate-shaped workpiece) transported by the robot hand 1 and placed on the hand body 13 so that it approaches or contacts the sensor surface 31, and then lower it from the lifted state. The misalignment calculation means 6 calculates the misalignment amount of the semiconductor wafer W from the reference position C1 based on the outer shape of the semiconductor wafer W (plate-shaped workpiece) acquired by the sensor 3. This configuration allows the robot hand 1 to calculate the misalignment amounts δx and δy of the semiconductor wafer W from the reference position without retracting from the frame 4, and to correct the misalignment of the semiconductor wafer W based on the calculated misalignment amount so that the semiconductor wafer W is placed at the reference position C1 of the hand body 13, etc. This reduces the transport time, including the process of correcting the misalignment of the semiconductor wafer W.

In this embodiment, the work lift mechanism 5 is equipped with multiple lift pins 512 that move up and down a predetermined distance, and is configured to lift and lower the semiconductor wafer W using the multiple lift pins 512, but the configuration of the work lift mechanism is not limited to this. For example, the work lift mechanism may be configured without lift pins 512, and instead perform the function of the work lift mechanism by appropriately moving the robot hand 1 up and down on the robot side to lift and lower the semiconductor wafer W placed and held on the hand body 13. In this case, the set of three stays 51 or three lift pins 512 shown in Figures 1 and 2, etc., can be omitted.

In this embodiment, it is not possible to correct the positional misalignment of the semiconductor wafer W in the θ direction, but the amount of positional misalignment δθ in the θ direction is calculated, and if necessary, the positional misalignment of the semiconductor wafer W in the θ direction can be corrected in a separate process.

This correction of positional misalignment in the θ direction is performed in another device as needed. For this reason, the positional misalignment calculation means 6 or control device 7 has the function of outputting the calculated positional misalignment amount to the outside. An example of such another device is a device equipped with a turntable that can correct positional misalignment in the θ direction by rotating the turntable. If the processing chamber has the function of correcting positional misalignment in the θ direction, the positional misalignment in the θ direction can be corrected in the processing chamber. Of course, not only the positional misalignment in the θ direction, but also the positional misalignment amounts in the X and Y directions may be output to the outside. Note that Figure 3 illustrates the positional misalignment amount being output to the outside from the control device 7.

Figures 9 to 16 show an aligner device B2 and a workpiece misalignment detection device A2 included therein according to a second embodiment of the present invention. The workpiece misalignment detection device A2 according to this embodiment differs from the first embodiment in the configuration of the stay 51 or lift pin 512 in the workpiece lift mechanism 5. Note that in these figures, members or parts that are similar or equivalent to those in the first embodiment are designated by the same reference numerals.

The workpiece misalignment detection device A2 is configured to function as an aligner device B2, which corrects the misalignment of the semiconductor wafer W (workpiece) relative to a reference position, by using a first robot hand 1 for loading the workpiece and a second robot hand 2 for unloading the workpiece after the misalignment has been corrected.

The first robot hand 1 and second robot hand 2 basically have the same configuration as the robot hand 1 described above in the first embodiment. That is, for example, they have a structure in which hand bodies 13, 23 are attached to supports 12, 22 installed on the end arm (not shown) of an articulated robot, and have the function of being able to move at least the hand bodies 13, 23 in a horizontal position and in a planar direction (X-Y direction) by control of a manipulator (not shown). The hand bodies 13, 23 have a planar shape resembling a fork with two prongs.

The sensor 3 has the same configuration as that described above for the first embodiment, and is capable of capturing an image of the outline of a planar object located below it through close, non-contact contact. The sensor 3 is attached, with the sensor surface 31 facing downward, to the underside of a support plate 41 that extends horizontally from the frame 4.

The work lift mechanism 5 has the function of lifting a semiconductor wafer W held by the first robot hand 1 and inserted into the frame 4 by a certain height from the hand body 13, and transferring the semiconductor wafer W to the hand body 23 of the second robot hand 2 while correcting for misalignment. In this embodiment, the work lift mechanism 5 has four stays 51 arranged so as not to interfere with the path of entry of the semiconductor wafer W into the frame 4 from one side in the X direction (left side in FIG. 9) by the first robot hand 1 and the path of removal of the semiconductor wafer W from the frame 4 to the other side in the X direction (right side in FIG. 9) by the second robot hand 2. The stays 51 have inward-facing horizontal portions 511 at their lower ends, and lift pins 512 protruding upward are provided on the horizontal portions 511. Each set of the four stays 51 and four lift pins 512 is provided corresponding to the sensor 3, and each set is actuated vertically a predetermined distance by an actuator (not shown), such as an air cylinder, located outside the frame 4.

As described above for the first embodiment, the misalignment calculation means 6 calculates the misalignment amount δx in the X direction, the misalignment amount δy in the Y direction, and the misalignment amount δθ in the θ direction of the semiconductor wafer W from the outer shape of the semiconductor wafer W acquired as an image by the sensor 3 (Figure 6).

The workpiece positional deviation detection device A2 configured as described above cooperates with the first and second robot hands 1 and 2 and the workpiece lift mechanism 5, which are driven and controlled by the control device 7, to form the aligner device B2, which operates, for example, as follows:

As shown in Figure 11, the robot hand 1, with the semiconductor wafer W placed and held on the hand body 13, moves in the X direction until the hand body 13 enters the correction reference position within the frame body 4 and positions the semiconductor wafer W below the sensor 3. At this time, the semiconductor wafer W is misaligned in the X-Y and θ directions relative to the reference positions C1 and N1 on the hand body 13. At this stage, the second robot hand 2 has been retracted from the frame body 4 on the opposite side of the first robot hand 1 in the X direction.

Next, as shown in FIG. 12, the lift pins 512 rise to lift the semiconductor wafer W from the hand body 13 and bring it close to the underside of the sensor 3, and as shown in FIG. 13, the first robot hand 1 is retracted from the frame body 4. In this state, the sensor 3 acquires the outer shape of the semiconductor wafer W as image data. The positional deviation calculation means 6 receives this image data and calculates the positional deviation amounts δx, δy, and δθ of the semiconductor wafer W in the X-Y and θ directions from the reference positions C1 and N1, as described above (FIG. 6).

Then, the semiconductor wafer W is transferred to the hand body 23 of the second robot hand 2 while correcting the positional deviation δx in the X direction and the positional deviation δy in the Y direction as follows:

As shown in Figure 14, the second robot hand 2 enters the frame 4, causing the hand body 23 to assume the correction reference position. This correction reference position is a position that substantially coincides with the correction reference position when the hand body 13 of the first robot hand 1 enters the frame 4, and the reference position C1 in the X-Y directions on the hand body 23 coincides with the reference position C1 in the X-Y directions on the hand body 13 when the first robot hand 1 assumes the correction reference position.

Next, as shown in FIG. 15, in order to correct the positional deviation δx, δy of the semiconductor wafer W relative to the hand body 23, the movement of the second robot hand 2 is controlled so that the hand body 23 moves δx, δy from the correction reference position. In this state, as shown in FIG. 16, the set of lift pins 512 is moved downward, and the semiconductor wafer W lifted by the lift pins 512 is transferred to the hand body 23. In this state, the semiconductor wafer W placed on the hand body 23 is positioned at its reference position C1 relative to the hand body 23.

In the procedure for correcting the positional deviation of the workpiece in this embodiment, as described with reference to Figures 14 and 15, the hand body 23 is placed at the correction reference position when the second robot hand 2 enters the frame 4, and then the hand body 23 is moved by the positional deviation amounts δx and δy from the correction reference position to correct the positional deviation of the semiconductor wafer W. Alternatively, the hand body 23 of the second robot hand 2 may be moved by the positional deviation amounts δx and δy before entering the frame 4 (the state shown in Figures 9 and 10, etc.), to perform the positional deviation correction, and then the second robot hand 2 may be entered into the frame 4. Alternatively, the second robot hand 2 may be entered into the frame 4 while performing the positional deviation correction by moving the hand body 23 by the positional deviation amounts δx and δy when entering the frame 4. In these cases, after the second robot hand 2 enters the frame 4, the set of lift pins 512 is moved downward, and the semiconductor wafer W held up by the lift pins 512 can be transferred to the hand body 23. In this state, the semiconductor wafer W placed on the hand body 23 is positioned at its reference position C1 relative to the hand body 23 (see Figure 16).

The second robot hand 2 can then transport the semiconductor wafer W to the next process while holding the semiconductor wafer W at the reference position C1 in the X-Y directions of the hand body 23. In this embodiment, the positional deviation of the semiconductor wafer W in the θ direction cannot be corrected either, but the amount of positional deviation δθ in the θ direction is calculated, and the positional deviation of the semiconductor wafer W in the θ direction can be corrected in a separate process as needed, just as in the first embodiment.

As described above, with the workpiece misalignment detection device A2 configured as described above and the aligner device B2 including it, the outer shape of the semiconductor wafer W as a plate-like workpiece can be acquired by the sensor 3 having the planar sensor surface 31, and the X-direction misalignment amount δx, Y-direction misalignment amount δy, and θ-direction misalignment amount δθ from the reference position of the semiconductor wafer W can be calculated from the image of the outer shape thus acquired. Therefore, the physical configuration for detecting the misalignment amount of the semiconductor wafer W can be configured to be thin.

The aligner device B2 includes a sensor 3, a work lift mechanism 5, a positional deviation calculation means 6, and a control device 7. The sensor 3 has a downward-facing sensor surface 31. The work lift mechanism 5 can lift a semiconductor wafer W (plate-shaped workpiece) transported by the first robot hand 1 and placed on the hand body 13 so that the workpiece W approaches or comes into contact with the sensor surface 31, and then lower the workpiece W from the lifted state. The positional deviation calculation means 6 calculates the positional deviation of the semiconductor wafer W from the reference position C1 based on the outer shape of the semiconductor wafer W (plate-shaped workpiece) acquired by the sensor 3. In this embodiment, while the semiconductor wafer W is being lifted by the work lift mechanism 5, the first robot hand 1 is retracted from the frame 4, and the hand body 23 of the second robot hand 2 is advanced into the frame 4, and the movement of the second robot hand 2 is controlled so that the semiconductor wafer W is placed at the reference position C1 of the hand body 23. In this state, the work lift mechanism 5 lowers the semiconductor wafer W, transferring the semiconductor wafer W to the hand body 23.

In this embodiment, the first robot hand 1 and the second robot hand 2 are appropriately advanced below the sensor 3 (sensor surface 31), and while the semiconductor wafer W is moved up and down below the sensor 3 by the work lift mechanism 5, the misalignment amount calculation means 6 calculates the misalignment amount of the semiconductor wafer W from the reference position C1 and corrects the misalignment. The second robot hand 2 can then transport the semiconductor wafer W handed over by the work lift mechanism 5 to the next process while holding it at the reference position C1 of the hand body 23. Thus, according to this embodiment, the first and second robot hands 1 and 2, the sensor 3, the work lift mechanism 5, the misalignment amount calculation means 6, and the control device 7 work together to appropriately correct the misalignment of the semiconductor wafer W placed on the first robot hand 1, and then transfer the semiconductor wafer W to the second robot hand 2, allowing it to be quickly transported to the next process. This makes it possible to shorten the transfer time, including the process of correcting the positional misalignment of the semiconductor wafer W and the transfer of the semiconductor wafer W from the first robot hand 1 to the second robot hand 2.

Of course, the scope of the present invention is not limited to the above-described embodiments, and all modifications within the scope of the claims are included within the scope of the present invention.

In the above-described embodiment, the semiconductor wafer W is prevented from coming into contact with the sensor 3 to avoid contamination of the surface of the semiconductor wafer W, but if contact is acceptable, the semiconductor wafer W may be brought into contact with the sensor 3.

A1, A2: Misalignment detection device, B1, B2: Aligner device, W: Semiconductor wafer (plate-shaped workpiece), W': Semiconductor wafer image, O1: Image center, C1: Reference center position, N1: Notch reference position, δx: X-direction misalignment, δy: Y-direction misalignment, δθ: θ-direction misalignment, 1: Robot hand (first robot hand), 13: Hand body, 2: Robot hand (second robot hand), 23: Hand body, 3: Sensor, 31: Sensor surface, 5: Work lift mechanism, 6: Misalignment calculation means, 7: Control device

Claims (4)

a robot hand having a hand body capable of placing and holding a plate-shaped workpiece;
A sensor having a downward-facing sensor surface that can detect the outer shape of a plate-like workpiece that is in proximity to or in contact with a lower part of the sensor surface;
a work lift mechanism that can lift a plate-shaped workpiece transported by the robot hand and placed on the hand body so that the plate-shaped workpiece approaches or comes into contact with the sensor surface, and can also lower the workpiece from the lifted state;
a positional deviation amount calculation means for calculating a positional deviation amount of the plate-shaped workpiece from a reference position based on the external shape of the plate-shaped workpiece in a state lifted by the work lift mechanism, the positional deviation amount being acquired by the sensor;
Equipped with
The aligner device is characterized in that the sensor surface has a planar shape corresponding to the outer shape of the plate-like workpiece and a size corresponding to the outer dimensions of the plate-like workpiece . The aligner device of claim 1 further includes a control means for controlling the robot hand so that, when the work lift mechanism lifts the plate-shaped workpiece and transfers it onto the hand body, the plate-shaped workpiece is placed at a reference position on the hand body based on the positional deviation amount calculated by the positional deviation amount calculation means. The aligner device of claim 1 or 2, further comprising a function for outputting the positional deviation amount calculated by the positional deviation amount calculation means to an external device. a work lift mechanism that is transported by the robot hand and that can lift the plate-shaped work placed on the hand body so that it approaches or contacts the sensor surface and can lower the plate-shaped work from the lifted state; a positional deviation amount calculation means that calculates a deviation amount of the plate-shaped work from a reference position based on the outer shape of the plate-shaped work in a state where it has been lifted by the work lift mechanism, which is acquired by the sensor; and a control means that controls the robot hand so that the plate-shaped work is placed at the reference position on the hand body based on the positional deviation amount calculated by the positional deviation amount calculation means when the plate-shaped work is lifted down by the work lift mechanism and transferred onto the hand body,
a plate-shaped workpiece carrying step of moving the robot hand so that the plate-shaped workpiece placed on the hand body is positioned at a correction reference position below the sensor;
an outer shape acquisition step of lifting the plate-shaped workpiece from the hand body by the work lift mechanism, bringing the plate- shaped workpiece close to or into contact with the sensor surface of the sensor, and acquiring the outer shape of the plate-shaped workpiece by the sensor;
a positional deviation amount calculation step of calculating a positional deviation amount in the XY direction from a reference position of the plate-like workpiece based on the acquired outer shape;
a position correction step of controlling the robot hand in the XY directions based on the positional deviation amount calculated by the positional deviation amount calculation means when the plate-shaped workpiece is lifted down by the work lift mechanism and transferred onto the hand body so that the plate-shaped workpiece is placed at a reference position on the hand body;
Including,
A method for correcting positional deviation of a plate-like workpiece, characterized in that the sensor surface has a planar shape corresponding to the outer shape of the plate-like workpiece and a size corresponding to the outer dimensions of the plate-like workpiece .