JP2008098565A - Aligner of wafer - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To constitute a structure which can treat both a 300 mm wafer and an 8-inch wafer in the aligner capable of angle alignment of centering, notching and the like, by holding the edge of a wafer. <P>SOLUTION: The structure comprises: a holding mechanism for holding the perimeter of a wafer by a switching operation; a rotation mechanism for rotating the holding mechanism to hold the wafer; and a sensor mechanism for detecting a specific shape of the perimeter of the wafer rotated by this rotation mechanism. In the aligner device of a wafer wherein the position of a wafer is determined by the operation of the holding mechanism, and the wafer is made to rotate to a desired direction by the rotation mechanism, the holding mechanism is equipped with at least two kinds of clampers 12 (12a-12d) and 13 (12a-12d) which can hold a wafer whose diameters differ. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an edge grip type pre-aligner device that is used in a semiconductor manufacturing apparatus or an inspection apparatus and performs angle adjustment such as wafer centering and notching.

In semiconductor manufacturing equipment, etc., a pre-aligner device is mainly used in combination with a wafer handling robot, and grips (grips) a wafer transferred from the robot and rotates the wafer to preliminarily make an outer periphery. This is a device that detects notches such as or flats and aligns them in a predetermined angular direction based on this, and determines the center position of the wafer itself (centering). This pre-aligner apparatus is installed in a so-called locally cleaned housing in which a downflow airflow that has passed through a filter is isolated by a box together with a wafer handling robot in a recent semiconductor manufacturing apparatus. In addition, a cassette opener (referred to as a POD opener or a FOUP opener) that opens and closes a cassette (FOUP or the like) that contains a wafer is provided on the side surface of the casing. Open and close cassettes without intruding. Then, while the wafer handling robot aligns the wafers in the cassette with the pre-aligner, the aligned wafer is transported to a processing apparatus installed adjacent to the housing. In the processing apparatus, for example, CVD, etching, etc. A predetermined process such as exposure is performed. Then, the wafer that has been processed by the processing apparatus is stored in the cassette again. In the case of this form, the housing constitutes a conveying device called a front end device or the like. In addition, a plurality of cassette openers described above are provided on the side of the housing, and a housing has been developed in which a wafer handling robot moves wafers while aligning with an aligner between a plurality of cassettes on the plurality of cassette openers. Yes. The form of the housing is a conveying device called a sorter. In any case, the pre-aligner is frequently used in a semiconductor manufacturing apparatus because it aligns the position and direction of the wafer.

By the way, while the outer diameter of recent wafers used in semiconductor manufacturing factories has shifted to larger sizes such as 300 mm, the use of 8-inch wafers has continued, so in semiconductor manufacturing equipment, wafers used in factories A device corresponding to the diameter is incorporated in the manufacturing apparatus. However, when these different-diameter wafers are used together in a factory, for example, in each production lot, the equipment in the production apparatus is often manually replaced with a device suitable for the wafer diameter. However, in particular, the recent wafer aligner apparatus needs to perform alignment only by gripping a limited part such as the edge of the wafer for the reason of miniaturization of semiconductor manufacturing, and the aligner apparatus is limited as described above. Since it is often installed in a space (housing), downsizing is also required, and it is difficult to configure so that wafers of different diameters can be aligned by simply replacing parts. Therefore, in particular, in the conventional aligner apparatus, there are few products that can deal with wafers of different diameters without replacing parts.
An object of the present invention is to construct a pre-aligner apparatus capable of aligning different diameter wafers without exchanging components or the like from such technical background and problems.

In order to solve the above problems, the present invention is configured as follows.
According to the first aspect of the present invention, a gripping mechanism that grips the outer periphery of the wafer by an opening / closing operation, a turning mechanism that rotates the gripping mechanism that grips the wafer, and a specific shape of the outer periphery of the wafer rotated by the turning mechanism are detected. And a sensor mechanism that determines a position of the wafer by an operation of the gripping mechanism, and rotates the wafer in a desired rotation direction by the turning mechanism. A wafer aligner provided with at least two types of clampers capable of gripping the wafer was obtained.
According to the invention of claim 2, the gripping mechanism includes an air cylinder fixed to the apparatus main body, a link mechanism that operates by an operating shaft of the air cylinder, and two mechanisms that can be operated simultaneously in opposite directions by the link mechanism. It comprises a clamper base and the at least two types of clampers provided on the clamper base, and the at least two types of clampers can simultaneously hold wafers having different diameters by operation of the air cylinder. A wafer aligner according to claim 1.
According to a third aspect of the present invention, when the wafers having different diameters are the first wafer and the second wafer having a smaller diameter, the clamper can hold the first wafer and And a second clamper that can hold the second wafer, and a first clamp arm that supports the first clamper extends from the clamper base and supports the second clamper. The clamp arm of the first clamper is extended from the clamper base, and the gripping position of the wafer of the first clamper is higher than the gripping position of the wafer of the second clamper. The wafer aligner according to claim 2 is provided.
According to a fourth aspect of the present invention, there is provided the wafer aligner according to the third aspect, wherein the apparatus main body is provided with wafer detection sensors for detecting the first and second wafers held by the first and second clampers, respectively. It was.
According to a fifth aspect of the present invention, the wafer detection sensor comprises a first wafer detection sensor capable of detecting the first wafer and a second wafer detection sensor capable of detecting the second wafer. When both the first wafer detection sensor and the second wafer detection sensor detect the wafer, it is determined that the first wafer exists in the first clamper, and the first wafer detection sensor detects the wafer. 5. The wafer aligner apparatus according to claim 4, wherein when the second wafer detection sensor detects no wafer and the second wafer detection sensor detects that the second wafer is present in the second clamper.
According to a sixth aspect of the present invention, the turning mechanism includes a motor fixed to the apparatus main body, and a turning base that can turn by the operation of the motor on the apparatus main body, and the gripping mechanism has the at least two types. 2 clamper bases that can move according to a linear guide laid on the swivel base, and a member that is operated by an air cylinder fixed to the apparatus main body, and is rotatably supported via a bearing. 2. A wafer aligner according to claim 1, further comprising a link mechanism for moving the two clamper bases in directions opposite to each other.
The invention of claim 7 includes at least a cassette opener that opens a lid of a wafer cassette containing a wafer, a wafer handling robot that conveys the wafer from the cassette opener, and a wafer aligner that aligns the wafer. In the wafer transfer system, the wafer aligner is the wafer aligner according to claim 1.
The invention of claim 8 is a semiconductor manufacturing apparatus for manufacturing a semiconductor by processing wafers having different diameters transferred by the wafer transfer system according to claim 7.
According to a ninth aspect of the present invention, there is provided a gripping mechanism having at least two types of clampers capable of gripping the outer circumferences of wafers having different diameters, a turning mechanism that rotates the gripping mechanism that grips the wafer, and the rotation mechanism that rotates the turning mechanism. A sensor mechanism for detecting a specific shape of each outer periphery of wafers having different diameters, and a detection sensor for detecting each of wafers having different diameters when the wafers having different diameters are placed on the gripping mechanism, In the wafer alignment method in which the position of the wafer is determined by the operation of the gripping mechanism and the wafer is rotated in a desired rotation direction by the turning mechanism, after the gripping mechanism is opened, one of the at least two types of clampers The wafer mounted on the wafer is gripped to determine the position of the wafer, and the detection sensor The specific shape of the outer periphery of the wafer is identified by the sensor mechanism that detects the outer periphery of the determined wafer while the wafer is rotated by the turning mechanism, and the specific shape is further moved to a desired position. The wafer alignment method was completed by rotating.

As described above, the present invention has the following effects.
(1) There is no replacement of parts due to the change of the wafer size, and the wafer size can be changed without stopping the apparatus by recognizing the changed wafer size by the sensor, thereby reducing the processing efficiency of the apparatus. do not do.
(2) Since it is not necessary to lay out a dedicated machine for each wafer size in the apparatus, the footprint in the apparatus can be greatly reduced and the cost can be reduced.

  Embodiments of the present invention will be described below.

  Hereinafter, a first example of an embodiment of the pre-aligner device of the present invention will be described with reference to the following drawings. 1 is a side sectional view of a gripping mechanism and a sensor mechanism of the pre-aligner apparatus according to the first embodiment, FIG. 2 is a top view of FIG. 1 and a sensor mechanism is omitted, and FIG. 3 is a partially enlarged view of FIG. 4 shows a side sectional view of the entire apparatus of Example 1, respectively.

  As shown in FIG. 4, this apparatus is generally composed of an aligner main body 0, a wafer holding mechanism placed on the aligner main body 0, and a sensor mechanism for detecting a notch on the outer periphery of the wafer held by the wafer holding mechanism. Yes. Inside the main body, a mechanism for realizing gripping of the wafer gripping mechanism and a turning mechanism for turning the wafer gripped by the gripping mechanism and the gripping mechanism are incorporated.

First, the wafer gripping mechanism will be described. 1a shows a wafer having a diameter of 300 mm. Reference numerals 12a, 12b, 12c, and 12d are 300 mm clampers that can sandwich and hold the edge portion of the 300 mm wafer 1a. The clampers 12a and 12c are provided at the tips of the clamp arms 11a and 11c extending from the clamper base 21, respectively. 12b and 12d clampers are provided at the tips of clamp arms 11b and 11d extending from the clamper base 22, respectively. The clamp arms 11a to 11d extend in the horizontal direction from the clamper bases 21 and 22 as shown in FIG. 1 and then extend in the vertical direction to hold the edge portion of the 300 mm wafer 1a.
Further, as a clamper for 200 mm capable of sandwiching an edge portion of a wafer having a diameter of 200 mm, clampers 13a and 13c are provided at the tips of clamp arms 23a and 23c extending from the clamper base 21, respectively. As shown in FIG. 2, 13a and 13c are provided so as to be positioned between the 300mm clampers 12a and 12c when viewed from above. Clampers 13b and 13d are provided at the ends of clamp arms 23b and 23d extending from the clamper base 21, respectively. Similarly, 13b and 13d are provided so as to be positioned between 300b clampers 12b and 12d when viewed from above as shown in FIG. The clamp arms 23a to 23d extend in the horizontal direction from the clamper bases 21 and 22 as shown in FIG. 1 and then extend in the vertical direction to grip the edge portion of the 200 mm wafer 1b. And lower than the group of 300 mm clampers 12a to 12d. That is, in order to transfer the 300 mm wafer 1a to this apparatus, as shown in FIG. 3, the rear surface of the 300 mm wafer 1a does not interfere with the clampers 13a, 13b, 13c, and 13d that hold the edge of the 200 mm wafer 1b. The wafer handling robot that operates in cooperation with is configured to ensure a necessary and sufficient clearance X that does not interfere when the wafers 1a and 1b are transported to the apparatus.
As described above, the 300 mm clampers 12a and 12d, and 12c and 12d operate so as to move toward and away from each other toward the center direction of the 300 mm wafer 1a to be gripped (a turning center axis 20 described later). The wafer 1a is gripped and released. Similarly, the 200 mm clampers 13a and 13d and 13c and 13d operate so as to contact and separate from each other in the center direction of the 200 mm wafer 1b to be held, thereby holding and releasing the 200 mm wafer 1b. These operations are performed by operating the clamper bases 21 and 22 so as to be in contact with each other. As shown in FIG. 1, the clampers 12a to 12d and 13a to 13d are formed with a step following the arc around the wafer, and when the gripping operation is performed as described above, the step is followed. The horizontal position of the held wafer is determined.
In the above description, the configuration of four clampers per wafer is described, but it goes without saying that the number of clampers may be three. For example, if the 300 mm clamper 12d is eliminated and the 12b is positioned at an intermediate position between the original 12b and 12d, the wafer is gripped at three peripheral points. Is similarly determined.

Next, the configuration of the gripping mechanism operation unit that realizes the gripping operation of the gripping mechanism will be described. The clamper bases 21 and 22 are connected to sliders 9a, 9b, 10a, and 10b respectively engaged with linear guide rails 9 and 10 mounted on the plate-like turning base 2. The linear guide rails 9 and 10 are provided in parallel. The clamper base 21 is connected to the sliders 9a and 10a, and the clamper base 22 is connected to 9b and 10b. Accordingly, the clamper bases 21 and 22 are guided linearly by the linear guide rails 9 and 10 and can move in the horizontal direction.
Further, one end of a link bar a25 and one end of a link bar b26 are connected to the clamper bases 21 and 22, respectively. The link bar a25 and the link bar b26 extend in the horizontal direction toward the through hole 24 provided in the substantially central portion of the turning base 2, and the other end thereof is one end of the link bar c27 and the link bar d28. And one end of the shaft is rotatably supported. The other ends of the link bars c and d are rotatably supported by the bridge bar 32, respectively. Near the center of the bridge bar 32, as shown in FIG. 2, the rotation axis of the bearing 19 is embedded so as to coincide with the center axis of the wafer held by the clamper. It is in contact. In addition, a cylinder bar 29 that comes into contact with the inner peripheral portion of the bearing 19 is provided in the vertical direction from the lower surface of the bridge bar 32. The cylinder bar 29 is inserted into the main body of the machine through the through hole 24 described above. The lower end of the cylinder bar 29 is connected to the output shaft of the air cylinder 18. The output shaft of the air cylinder 18 moves up and down by compressed air. The main body of the air cylinder 18 is fixed inside the main body of the machine. Further, the side surface of the cylinder bar 29 is connected to a guide 30 provided in the vertical direction inside the main body of the machine, and the cylinder bar 29 can be operated in the vertical direction by the operation of this and the air cylinder 18. .
Therefore, the clamper bases 21 and 22 operate so that the link bars a to d are simultaneously operated by the ascending operation of the air cylinder 18 so as to be close to the extending shaft of the cylinder bar 29, that is, the rotating shaft of the bearing 19. That is, by this operation, the 300 mm clamper 12 and the 200 mm clamper 13 grip the edge of the wafer. Similarly, the clamper bases 21 and 22 operate so that the link bars a to d are simultaneously operated by the lowering operation of the air cylinder 18 and are separated from the extending shaft of the cylinder bar 29, that is, the rotating shaft of the bearing 19. That is, by this operation, the 300 mm clamper 12 and the 200 mm clamper 13 open the edge of the wafer.

Next, a turning mechanism that rotates (turns) the wafer held by the holding mechanism will be described. As described above, one end of the hollow cylindrical rotary shaft 3 is connected to the lower surface of the through hole 24 provided near the center of the turning base 2. A pulley 5 is connected to the other end of the rotating shaft 3. The outer peripheral surface of the rotating shaft 3 is fitted so that the inner peripheral surface of the bearing 4 is in contact therewith. The rotation axis of the bearing 4 coincides with the rotation axis of the bearing 19, and this is the turning center axis 20. The turning center axis 20 is provided so as to coincide with the center axis of the wafer held by the clamper 12 or 13. The outer peripheral surface of the bearing 4 is held by the main body 0 of the machine. Therefore, the turning base 2 can rotate on the rotating shaft of the bearing 4 together with the rotating shaft 3 and the pulley 5. A belt 8 is wound around the outer periphery of the pulley 5. A pulley 7 is also wound around the belt 8. The pulley 7 is connected to the output shaft of the motor 6, and the motor 6 is connected to a control device (controller) (not shown). The control device also controls the air cylinder 18.
Therefore, the turning base 2 rotates on the turning center shaft 20 via the belt 8 by the rotation of the motor 6. On the other hand, clamper bases 21 and 22 are placed on the turning base 2 via linear guides 9 and 10, and the clamper bases 21 and 22 are fixed inside the main body via link bars a to d and the like. Although connected to the air cylinder 18, due to the action of the bearing 19 provided on the bridge bar 32, regardless of the vertical movement of the air cylinder 18, that is, regardless of the gripping state of the clampers 12, 13, etc., the turning base 2 can rotate (turn).

Next, a description will be given of a sensor mechanism that detects the position of a notch or the like on the outer peripheral portion of the wafer when the wafer held by the holding mechanism is turned by the turning mechanism. Several inverted L-shaped sensor bars 31 are erected on the upper surface of the main body 0 of this machine, and sensors 14 a and 14 b for detecting notches and the like of the 300 mm wafer 1 a near the tip of the sensor bar 31 from the turning center shaft 20. It is arranged at a position near 150 mm. Similarly, sensors 15a and 15b for detecting notches and the like of the 200 mm wafer 1b are disposed near the tip of the sensor 15a and 15b in the vicinity of 100mm from the turning center axis 20. Further, on the upper surface of the main body 0, the 300 mm wafer 1a is detected at a position of 100 mm or more and 150 mm or less from the turning center axis 20 in order to automatically identify the 300 mm wafer 1a and the 200 mm wafer 1b placed on the gripping mechanism. The sensor 17 for detecting the 200 mm wafer 1b is disposed at a position of 100 mm or less from the turning center axis 20.
Therefore, the wafer held by the holding mechanism is rotated by the action of the turning mechanism while being held, and the position of the notch or the like is determined by the action of the sensor mechanism.
As described above, the wafer held by the holding mechanism is determined in the horizontal direction (referred to as centering) so that the center axis of the wafer coincides with the turning center axis 20 by the holding operation of the holding mechanism, and the sensor mechanism and the turning mechanism. The position of the notch or the like is determined by the action of the above, and the wafer can be rotated so that the notch or the like comes to a desired position.

Next, the operation of the machine configured as described above will be described.
The operation of the apparatus after the 300 mm wafer 1a is mounted on the apparatus by a wafer handling robot (not shown) will be described.
First, the apparatus opens the clampers 12a to 12d and the clampers 13a to 13d by the lowering operation of the cylinder 18 and prepares for mounting the wafer.
Next, when the 300 mm wafer 1a is mounted on this apparatus by a wafer handling robot or the like, the clampers 12a to 12d and the clampers 13a to 13d are closed by the ascending operation of the cylinder 18, and the gripping mechanism grips the 300mm wafer 1a.
After the 300 mm wafer 1a is gripped, the wafer detection sensor 16 detects the wafer, and the sensor 17 also checks whether the wafer is detected.
When the detection sensors 16 and 17 are detected, it is recognized that a 300 mm wafer is mounted on the apparatus, and the turning base 2 is turned using the motor 6 as a drive source while holding the wafer by the holding mechanism. In this case, only the detection signals of the sensors 14a and 14b are employed to specify the position of the notch or the like of the 300 mm wafer 1a. When the position of the notch or the like can be specified, the turning base 2 is further rotated (alignment operation is performed) so that the notch position comes to a desired position.
If the 200 mm wafer 1b is mounted on the clampers 13a to 13d in this machine, the gripping mechanism similarly grips the 200mm wafer 1b, and then the signals of the detection sensors 16 and 17 are confirmed. When the detection and the detection sensor 17 detect the wafer, it is recognized that a 200 mm wafer is mounted on the apparatus, and an alignment operation similar to the above is executed while the wafer is held by the holding mechanism.
In this way, this machine is equipped with the clampers 12a to 12d and 13a to 13d mounted on a common clamper base so that they can operate integrally, and these different diameter clampers are erected from the clamper base in the height direction. Since they are at different positions, wafers of different diameters can be mounted without interfering with each other. In addition, since the gripping mechanism simultaneously operates these different diameter clampers simultaneously, the gripping operation can be performed without any problem even if the different diameter wafer is mounted on any clamper. In addition, regardless of whether or not the gripping mechanism performs a gripping operation, the gripping mechanisms can be turned by the turning mechanism.

Side sectional view of a gripping mechanism and a sensor mechanism of the pre-aligner device of Embodiment 1. FIG. 2 is a top view of FIG. 1 with the sensor mechanism omitted. Partial enlarged view in FIG. Side sectional view of the entire machine of Example 1

Explanation of symbols

DESCRIPTION OF SYMBOLS 0 Main body 1a 300mm wafer 1b 200mm wafer 2 Turning base 3 Rotating shaft 4 Bearing 5 Pulley 6 Motor 7 Pulley 8 Belt 9 Linear guide rail 10 Linear guide rail 9a-b Slider 10a-b Slider 11a-d Clamp arm 12a-d Clamper 13a -D clamper 14a-b 300mm wafer sensor 15a-b 200mm wafer sensor 16 300mm wafer detection sensor 17 200mm wafer detection sensor 18 air cylinder 19 bearing 20 turning center shaft 21 clamper base 22 clamper base 23a-d clamp arm 24 through hole 25 Link bar a
26 Link bar b
27 Link bar c
28 Link bar d
29 Cylinder bar 30 Guide 31 Sensor bar 32 Bridge bar

Claims (9)

A gripping mechanism for gripping the outer periphery of the wafer by an opening / closing operation, a turning mechanism for rotating the gripping mechanism for gripping the wafer, and a sensor mechanism for detecting a specific shape of the outer periphery of the wafer rotated by the turning mechanism. In the aligner device of the wafer, the position of the wafer is determined by the operation of the gripping mechanism, and the wafer is rotated in a desired rotation direction by the turning mechanism.
An aligner apparatus for a wafer, wherein the gripping mechanism includes at least two types of clampers capable of gripping wafers having different diameters.   The gripping mechanism includes an air cylinder fixed to the apparatus main body, a link mechanism that operates by an operating shaft of the air cylinder, two clamper bases that can simultaneously operate in opposite directions by the link mechanism, and the clamper base The at least two types of clampers provided on the wafer, wherein the at least two types of clampers can simultaneously hold the wafers having different diameters by operation of the air cylinder. 2. The wafer aligner according to 1. When the wafers having different diameters are a first wafer and a second wafer having a smaller diameter,
The clamper comprises a first clamper capable of gripping the first wafer and a second clamper capable of gripping the second wafer, and a first clamp arm supporting the first clamper is provided. A second clamp arm that extends from the clamper base and supports the second clamper extends from the clamper base, and the gripping position of the wafer of the first clamper is the position of the wafer of the second clamper. 3. The wafer aligner according to claim 2, wherein the first and second clamp arms are provided to be higher than a holding position.   4. The wafer aligner according to claim 3, wherein a wafer detection sensor for detecting the first and second wafers held by the first and second clampers is provided in the apparatus main body.   The wafer detection sensor comprises a first wafer detection sensor capable of detecting the first wafer and a second wafer detection sensor capable of detecting the second wafer, and the first wafer detection sensor When both of the second wafer detection sensors detect the wafer, it is determined that the first wafer exists in the first clamper, the first wafer detection sensor does not detect the wafer, and the first 5. The wafer aligner according to claim 4, wherein when the second wafer detection sensor detects the wafer, it is determined that the second wafer exists in the second clamper. The turning mechanism is composed of a motor fixed to the apparatus main body, and a turning base capable of turning by the operation of the motor on the apparatus main body,
The gripping mechanism mounts the at least two types of clampers and has two clamper bases movable according to a linear guide laid on the swivel base, and a bearing on a member operated by an air cylinder fixed to the apparatus main body. 2. A wafer aligner according to claim 1, further comprising: a link mechanism that is rotatably supported by the two clamper bases and that moves the two clamper bases in directions opposite to each other.   A wafer transfer system comprising: a cassette opener that opens a lid of a wafer cassette that contains a wafer; a wafer handling robot that transfers the wafer from the cassette opener; and a wafer aligner that aligns the wafer. The wafer transfer system according to claim 1, wherein the aligner is a wafer aligner according to claim 1.   8. A semiconductor manufacturing apparatus for manufacturing a semiconductor by processing wafers having different diameters transferred by the wafer transfer system according to claim 7. A gripping mechanism having at least two types of clampers capable of gripping the outer circumferences of wafers having different diameters, a turning mechanism that rotates the gripping mechanism that grips the wafer, and a wafer having different diameters rotated by the turning mechanism. A sensor mechanism for detecting a specific shape of the outer periphery, and a detection sensor for detecting each of the wafers having different diameters when the wafers having different diameters are placed on the gripping mechanism, and In the wafer alignment method of determining the position of the wafer and rotating the wafer in a desired rotation direction by the turning mechanism,
After opening the gripping mechanism, the wafer mounted on one of the at least two types of clampers is gripped to determine the position of the wafer, and the size of the wafer is determined by the detection sensor, and the turning mechanism While rotating the wafer, the sensor mechanism for detecting the determined outer periphery of the wafer identifies the specific shape of the outer periphery of the wafer, and further rotates the specific shape to a desired position to complete the alignment. A wafer alignment method characterized by the above.

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