JPH0445554A - Method and device for transforming plate body - Google Patents

Abstract

PURPOSE:To transfer a plate body safely and surely without causing dust by displacing the four directions of the specified straight directions of a second plate body and the directions perpendicular to these specified straight directions. CONSTITUTION:Based on the operation results of a computer, a motor 51 operates, receiving the instruction of the computer, and the positions of a gripper 7 and a lifter 8 are corrected in the direction of the X axis and the positions of the gripper 7, the lifter 8, and a quartz boat 12 are adjusted in vertical direction (Z axis direction). Sensors 9, 9, 10 and 10 are analog output noncontact reflection type optical sensors, and it detects the position of the target groove of the quartz boat, by the reciprocation in X axis direction and the elevation. The analog output signals from the sensors 9, 10 and 10 are coverted into digital signals with an A/D converter, and a computer analyzes these digital signals, and the correction of positions in the Y, x, y, and z and X axes of the quartz boat can be performed accurately.

Description

DETAILED DESCRIPTION OF THE INVENTION A. Field of Industrial Application The present invention relates to a method and device for transferring a plate-like object, and for example, to a method and device for transferring a semiconductor wafer.

BACKGROUND OF THE INVENTION Chemical vapor deposition (CVD) equipment is widely used to form deposited films such as silicon oxide films on the surfaces of semiconductor wafers. Semiconductor wafers (hereinafter simply referred to as wafers) are
It is made of a semiconductor single crystal such as silicon or gallium-arsenic and has a thin disk shape with a thickness of several hundred micrometers, and is usually placed in a large number (for example, two
5 sheets) and loaded into the CVD equipment together with the boat to undergo CVD processing. This boat has four horizontally positioned bars for supporting wafers, these bars are provided with grooves at a predetermined pitch, and the wafers are inserted into these grooves and horizontally positioned at predetermined intervals. placed vertically on the boat. Since this boat is heated together with the wafers in the CVD apparatus, quartz is used as the material for the boat. Hereinafter, this boat will be referred to as a quartz boat.

The wafers are placed on a mounting device (called a cassette) separate from the quartz boat and transported near the CVD apparatus,
At this point, it will be transferred to the quartz boat mentioned above. Furthermore, the wafers that have undergone the CVD process are transferred from the quartz boat to a cassette and transported to the next process. The above cassette has many grooves on the side wall for inserting wafers, and is made of Teflon resin to reduce friction with the wafers during transportation and wafer transfer.The wafer spacing is usually The cassettes and the quartz boat are made the same so that the transfer work can be carried out easily.

When transferring the above wafers, set the cassette on the cassette table and the quartz boat on the boat table, lift the wafers with a lifter, and then use a gripper called a gripper to pick up, for example, 25 wafers at once. to hold. Then, the gripper is raised to remove the wafer from the cassette or quartz boat, and then the gripper is moved horizontally (
or move both tables horizontally) to position the wafer above the quartz boat or cassette. Next, the lifter is raised and then the gripper is lowered to place the wafer on the lifter, and the wafer is released and the gripper is raised.Next, the lifter is lowered and the wafer is placed on the quartz boat or cassette. place

It is also conceivable that a pair of gripper handles and lids be provided above and below both the cassette table and the boat table.

By the way, since the quartz boat is heated together with the wafer in the CVD apparatus, as it is repeatedly used, distortion occurs and the groove spacing becomes out of order.

When the quartz boat becomes distorted in this way, the wafer cannot be held securely by the gripper, and some wafers may no longer be held, or the wafer may slide against the four bars or cassette of the quartz boat. Undesirable dust generation, damage, or chipping may occur.

Conventionally, the following measures have been taken to resolve such troubles.

(1), II Wafers are transferred between the cassette and the quartz boat with only mechanical precision in mind, and if the quartz boat becomes distorted, it is discarded.

(2) One dummy groove is provided on the quartz boat, the position of this dummy groove is detected, and based on this detection result, the position is corrected only in the direction between the quartz boat and the cassette (X-axis direction) do.

(3) Detect the positions of the three grooves on the quartz boat, and based on these detection results, calculate the circumferential direction around the X-axis, Y-axis, and Z-axis (vertical axis) of the quartz boat. (The gripper has a structure that allows correction in these three directions.)

In method (1) above, the price of a quartz boat is 10 wafers.
The cost is 50,000 to 500,000 yen per piece (depending on the size of the Ueno bag), which is uneconomical. The method (2) above is based on the assumption that the dummy groove and the groove into which the periphery is inserted will be deformed to the same extent.
If this assumption does not hold, position correction becomes almost impossible. Even with method (3) above, the position correction is not sufficient,
In particular, when transferring wafers from a quartz boat to a cassette, it is impossible to detect the position of the groove because the peripheral edge of the wafer is inserted into the groove.

Various elements are formed on the surface of the wafer by photolithography after the CVD process. ). Along with the above etching and cleaning of Ueno 1, the four bars mentioned above gradually become thinner and the width of the groove becomes larger, as the etching and cleaning are repeated. When the pitch becomes out of order, problems similar to those described above will occur.

C0 Purpose of the Invention The present invention provides that when a plate-like object is transferred between a first and a second plate-like object member, distortion occurs in one of the plate-like object mounting members (for example, the above-mentioned quartz boat). Even if the plate-shaped object (for example, the aforementioned wafer) is thin or thin, it can be safely and reliably processed without causing damage such as scratches or chips to the plate-shaped object (for example, the aforementioned wafer) or generating undesirable dust. It is an object of the present invention to provide a method and device for transferring a plate-like object.

20 Structure of the Invention The first invention provides that when transferring the plate-like body between the first plate-like body Wli and the plate-like body mounting member of the placement member color member, the second plate-like body a step of detecting the positions of a plurality of places on the mounting member; and, based on the detection results, detecting a predetermined linear direction of the second plate-shaped body mounting member, this predetermined linear direction, and this predetermined straight line. By displacing the first plate-shaped body in four directions including three circumferential directions centered on three directions orthogonal to the direction, and one linear direction orthogonal to the predetermined direction, Aligning the positional relationship of the second plate-shaped body mounting member with respect to the member, and gripping the plate-shaped body on the first or second plate-shaped body mounting member to place the plate-shaped body on the first or second plate-shaped body mounting member. Take it out from the second plate-shaped object mounting member,
Next, the plate-shaped body is moved relative to the first and second plate-shaped body mounting members and inserted into the second or first plate-shaped body mounting member, and then the plate-shaped body is inserted into the second or first plate-shaped body mounting member. The present invention relates to a method for transferring a plate-shaped object, which includes a step of releasing the grip on the plate-shaped object.

A second invention is a plate-like object transfer device that transfers a plate-like object between a first plate-like object mounting member and a second plate-like object mounting member, wherein the second plate-like object a position detection means for detecting the positions of a plurality of locations on the body placement member; and a predetermined linear direction of the second plate-shaped IT member and this predetermined linear direction based on the detection result of the position detection. By displacing the three directions perpendicular to this predetermined linear direction, the three circumferential directions, and the three circumferential directions, and one linear direction perpendicular to the predetermined direction,
a positional relationship matching means for aligning the positional relationship of the second plate-shaped body mounting member with respect to the first plate-shaped body mounting member; and the plate on the first or second plate-shaped body mounting member. gripping the shaped body and taking it out from the first or second plate-shaped body mounting member;
Next, the plate-shaped body is moved relative to the first and second plate-shaped body mounting members and inserted into the second or first plate-shaped body mounting member, and then the plate-shaped body is inserted into the second or first plate-shaped body mounting member. a plate-shaped body gripping means for releasing the grip of the plate-shaped body, and each of the displacement means for displacing the plate-shaped body in at least the four directions is combined to form a uni-groove structure. Related to transfer equipment.

E, Example The present invention will be explained in detail below.

The wafer transfer device that transfers wafers between the cassette and the quartz boat is composed of the following parts.

(i) Positioning mechanism of 8 quartz boats and 4 of quartz boats
A table equipped with a mechanism capable of minute movement on axes (Y axis, eX axis, ey axis, θ2 axis).

(ii) A table equipped with a cassette positioning mechanism.

(ii) A lid for raising and lowering the wafer.

(iv) An analog output sensor equipped with a mechanism that can be moved up and down (Z-axis) to detect a target groove for detecting deformation of a quartz boat.

(The sensor is raised and lowered by the same ball screw as the lifter, and the selection mechanism selects which of the two to be raised and lowered.) (V): The wafer raised by the lifter is held or held A gripper that moves the wafer up and down (Z-axis).

(When the lifter lifts the wafer, align the wafer storage groove of the quartz boat and cassette with the wafer insertion groove of the gripper in the vertical direction, lower the gripper to the upper end of the quartz boat and cassette, and then insert the wafer into the wafer insertion groove of the lifter. (If the wafer whose peripheral edge is inserted is inclined, the wafer should fit smoothly into the groove of the gripper.) (When the wafer is passed from the gripper to the lid and then the lifter is lowered, Align the wafer storage groove of the quartz boat and cassette with the wafer insertion groove of the gripper in the vertical direction, lower the gripper to the top of the quartz boat and cassette, and use the wafer insertion groove of the gripper as a guide to insert the wafer into the quartz boat and cassette. (■) A carriage equipped with a mechanism for horizontally moving (Y-axis) the lifter, sensor, and gripper between the quartz boat and the cassette on the same base.

(vi) On the four bars of the quartz boat, target grooves for deformation detection are carved in two places in each of the wafer storage grooves and these grooves. The Y-axis and the Y-axis are detected by sensors at the target grooves of the lower left and right bars.

The quartz boat has a structure shown in FIG. 13 in a plan view, FIG. 14 in a front view, and FIG. 15 in a side view.

The quartz boat 13 has an upper pair of bars 21.21; a lower pair of bars 22.22; a connecting bar 23.23 connected to the bar 21.21 at both ends; and a connecting bar 23.23 connected to the bar 22.22 at both ends. with the connecting bar 24.24 connected with; the upper bar 21.2
1 and a connecting bar 25.25 connecting the connecting bar 24.24 at both ends. Upper and lower bars 21.21
．． 22.22 has wafer insertion grooves 21a, 21a, . . . into which peripheral portions of wafers (not shown) are inserted.
22a, 22a, .
2b is engraved. Two places near both ends of one lower bar 22 have chamfers 22c, 22c, 22 on the lower ridge.
C122c is provided, and XVI-XV in FIG.
As shown in FIG. 16, which is an enlarged sectional view taken along line I, the chamfered portion of the bar 2.2 is fitted into an M-shaped stand 13 (both shown by imaginary lines) that stands up from the boat table 4. A quartz boat 12 is positioned and placed on a boat table (not shown). Further, from both ends of the lower bar 22, legs 22d, 22 are extended downward.
d extends so that the quartz boat 12 can be stably placed in a place other than the boat table, and ears 26.26.2 are provided at both ends of the upper bar 21.210 facing outward.
6.26 is attached to make handling easier.

FIG. 1 shows the wafer transfer device, and FIG. 1(a) is a perspective view of the wafer transfer device with the lid located in the through hole of the cassette placement section, and FIG. FIG. 3 is a perspective view of the quartz boat mounting portion located at the position of the through hole.

A cassette table 2 and a boat table 4 are provided on the upper surface of the apparatus main body 1, and through holes 2a and 4a are provided in both tables 2.4, respectively, so that a cover 8 can be inserted therethrough. A guide 3.3 for positioning the cassette is attached to the cassette table 2, and a pair of rollers 5.5 for clamping a quartz boat and fixing it to the boat table 4 are attached to the boat table 4, respectively. Device body 1
A through hole 6 is provided on the upper surface so that the gripper 7 can reciprocate in the direction along the line connecting the through holes 2a and 4a, that is, in the X-axis direction.
is provided.

The outline of the procedure for transferring wafers from the cassette to the quartz boat is as follows.

(1) As shown in FIG. 1(a), the gripper 7 and lid 8 are positioned on the side of the through hole 2a, and the cassette 11 containing the wafer W is placed on the cassette table 2 as shown by the imaginary line arrow. Place it. Guide 3 for positioning the cassette 11
．． It is done by 3. At this step, Figure 1(b)
The quartz boat 12 is placed on the boat table 4 as shown by the imaginary line arrow, and is clamped and fixed with rollers 5.5.

(2) Next, the sensor 9.9.10.10 for detecting the target groove of the quartz boat 12 ascends through the through hole 4, moves in the X-axis direction, and moves to the target groove 21b, 21.
b, 21b, 21b, 22b, 22b, 22b, 22b
The position in the horizontal direction (X-axis direction) is detected. This detection is performed by moving the upper and lower bars 21 in the X-axis direction parallel to each other.
．． 22 by sensor 9.10. Further, the sensor 10.10 detects the position of the target groove of the bar 22 in the Y-axis direction by moving the boat table 4 in the horizontal direction (Y-axis direction) perpendicular to the X-axis.

Next, the sensor 9.9 moves up and down to detect the position of the target groove of the bar 21 in the vertical direction (X-axis direction). Based on these detection results, the wafer insertion groove (first
The three-dimensional positional deviation of 21a and 22a) in FIG. 3 is measured.

(3) A computer performs calculations based on the position detection of the target groove in the X-axis, Y-axis, and In order to position the quartz boat at the optimal position when inserting the peripheral edge into the wafer insertion groove of the quartz boat, θx and e in the Y-axis direction and the circumferential direction around the X-axis, Y-axis, and Z-axis are adjusted.
Operate the boat table 4 in the y and eZX axis directions.

(4) First, the gripping portion 7C17C of the gripper 7 descends from above the cassette 11.

(5) Next, the lifter 8 ascends through the through hole 2a,
The wafer W in the cassette 11 is supported. A large number of wafer insertion grooves 8a are cut into the upper surface of the lifter 8. and,
The wafer W is separated from the cassette 11.

At this time, the wafer insertion groove 7d of the gripper functions as a guide when the wafer is raised.

(6) First, the wafer clamping portion 7C17C of the gripper clamps the wafer W, and then ascends. Wafer W is lifter 8
The lifter 8 moves away from the through hole 2a and descends below the through hole 2a.

(7) Next, the carriage under the boat table 4 (described in detail later in FIG. 8) moves along the X axis to move the gripper 7 and lifter 8 to the vertical position relative to the quartz boat 12. let

(8) First, the carriage is finely adjusted in the X-axis direction based on the computer calculation results in section (3) above, and the position is adjusted in the Y, θX, θy, and ez-axis directions in section (3) above. The gripper 7 and lifter 8' are accurately aligned in the vertical direction with respect to the quartz boat 12 that has been made.

(9) First, the gripper gripping portion 7C17C descends from above the quartz boat 12 to near the upper bar 21, 21 of the quartz boat.

0ω0 Next, the lifter 8 moves up through the through hole 4a and supports the wafer W. The wafer W is held in the gripper holding part 7C1
Leave 7C.

(11), the gripper's gripping part 7C17C releases the wafer gripping state, the lifter 8 descends, the wafer W is separated from the lifter 8, its peripheral part is inserted into the wafer insertion groove of the quartz boat 12, and the wafer W is placed in the quartz boat 12. It is placed on the boat 12. At this time, the wafer insertion groove 7d of the gripping portion of the gripper functions as a guide when sewing the wafer W underlay.

07J, when the wafer W is placed on the quartz boat 12, the gripping portion 7C17C of the gripper 7 rises together with the arm 7b to prepare for the next transfer of the wafer from the quartz boat to the cassette.

The unprocessed wafers transferred from the cassette to the quartz boat are loaded into a CVD apparatus together with the quartz boat, and subjected to CVD processing. The processed wafer that has been subjected to the CVD process is discharged from the CVD apparatus together with the quartz port, transferred to a cassette, and transported to the next process.

The outline of the procedure for transferring processed wafers from a quartz boat to a cassette is as follows. However, Fig. 1(a)
, (b), the solid line and the virtual line are reversed.

(21) As shown in FIG. 1(b), the gripper 7 and the lid 8 are located on the side of the through hole 4a, and the quartz boat 12 containing the wafers W is placed in the boat as shown by the imaginary line arrow. It is placed on table 4 and clamped with rollers 5.5.

In this step, the cassette 11 is placed on the cassette table 2 and positioned by the guide 3.3 as shown by the phantom line arrow in FIG. 1(a).

(22) Next, in the same manner as in section (2) above, the sensor 9.
The position of the target groove of the quartz boat 12 is detected by 9.10.10.

(23) Next, in the same manner as in section (3) above, the port table 4 moves in the Y-axis and the θx, By, and θ2-axis directions, and the position of the quartz boat 12 is corrected.

(24) Next, in the same manner as in section (8) above, the carriage is finely adjusted in the X-axis direction, and the gripper 7
and accurately align the lifter 8 in the vertical direction.

(25) Next, the gripping parts 7c, 7c of the gripper 7 descend from above the quartz boat 12.

(26) Next, the lifter 8 moves up through the through hole 4a and supports the wafer W in the quartz port 12. and,
The wafer W leaves the quartz boat 12. At this time, the wafer insertion groove 7d of the gripper functions as a guide when the wafer is raised.

(27) Next, the wafer holding parts 7c, 7c of the gripper
grips the wafer W, and then rises. The wafer W leaves the lifter 8, and the lifter 8 descends below the through hole 4a.

(2B) Next, the aforementioned carriage moves along the X axis to move the gripper 7 and lifter 8 to the vertical position relative to the cassette 11.

(29) Next, the gripper 7C17C of the ripper descends from above the cassette 11 and inserts the wafer W into the cassette 11 without contact.

(30) Next, the lifter 8 moves up through the through hole 2a and supports the wafer W. The wafer W is held in the holding part 7 of the gripper.
Leave C17C.

(31) The gripper gripping portion 7C17C releases the wafer gripping state, the lifter 8 descends, and the wafer W is transferred to the lifter 8.
The peripheral edge of the wafer insertion groove 1 of the cassette 11
ta, and the wafer W is placed on the cassette 11. At this time, the wafer insertion groove 7d of the gripping portion of the gripper functions as a guide when the wafer W is lowered.

(32) When the wafer W is placed on the cassette 11, the gripping portion 7C17C of the gripper 7 rises together with the arm 7b to prepare for the transfer of the unprocessed wafer from the next cassette to the quartz boat.

Next, the mechanism of movement of the boat table 4 in the Y, θX, θy, and θ2 axis directions will be explained with reference to FIG.

The boat table 4 has the above-mentioned M-shaped stand 13.13 and a flat-topped stand 14.14, and one lower bar 22 of the quartz boat 12 with the above-mentioned chamfer is attached to the stand 13.1.
3, the other lower bar 22 is supported on the platform 14.14;
A quartz boat 12 is positioned and placed on the boat table 4 as described above, and is clamped and fixed by a pair of rollers 5.5. The sensor 9.9 ascends through the through-hole 4a of the boat table 4 and the through-hole 28a of the first fixed table 28 to which the θχ and ey-axis operating machines (to be described later) are attached, and as described above, the sensor 9.9 moves up to the target of the quartz boat 12. Groove 21b
, 21b, 21b, 21b, 22b, 22b, 22b,
The position of 22b is detected. Sensors are 9.9 and 10.10
There are two pairs of (see Figures 1(a) and (b)), but the second
In the figure, only 9.9 sensors are shown for simplification.

Under the boat table 4 is the exey axis actuator #I31.
．． 31 is attached to the table 28, the second attachment table 29 is attached to the Y-wheel actuation mechanism 32, and the third attachment is the table 30 to which the θ2-axis actuation mechanism 33 is attached.
They are located horizontally in this order. Actuation mechanism for each axis 31.3
1.32.33 is motor 31M, 31M, 32M, 3
By driving the 3M, the rollers 31a, 31a, 32a, and 33a at the tips are moved forward and backward by a built-in ball mechanism (details will be explained later with reference to FIG. 7).

The first installation is for table 28, and the second installation is for table 2.
9 is movably supported in the following manner.

As shown in FIG.
The second attachment is supported by the table 29 so as to straddle the rail 29c provided on the table 29 and guided by the rail 29c so as to be able to reciprocate in the Y-axis direction. Furthermore, as shown in FIG. 4, in the second mounting, the Y-wheel operating mechanism 32 is mounted on the plate 29a, and the roller 32a at the tip of the Y-wheel operating mechanism is mounted vertically on the table 29. Installation is on table 2
The roller receiver fixed to the lower part 8 is in contact with the plate 28b. In the roller holder, the plate 28b and the roller 32a are tensioned by an elastic member (not shown) such as a spring.
2a is designed such that the roller receiver is always in contact with the plate 28b.

Then, the operation of the Y-wheel operating mechanism 32 and the rail 2 in FIG.
9c and the saddle 28c, the first attachment allows the table 28 to reciprocate in the Y-axis direction.

The second installation is table 29, the third installation is table 3
It is movably supported relative to 0 in the following manner.

As shown in FIG. 5A, which is a cross-sectional view along the X-axis direction of FIG.
The ez-axis shaft moving mechanism 33 is attached to the second attachment point 0a, and the roller receiver fixed downward to the table 29 is attached to the plate 2.
The roller 33a at the tip of the eZ-axis fine operating mechanism 33 comes into contact with the roller 9b. In the roller holder, the plate 29b and the roller 33a are tensioned by an elastic member (not shown) such as a spring, and the roller 32a
The roller receiver is always in contact with the plate 29b.

Further, as shown in FIG. 5B, which is a cross-sectional view along the Y-axis direction of FIG. The table 29 is rotatably supported by a bearing (for example, a thrust bearing) 30b provided above, and by the operation of the 02 actuation mechanism 33, the table 29 is mounted on the table 30 for the second mounting on the shaft 29d, and for the third mounting on the table 30. On the other hand, it is configured to rotate in the θ2 axis direction about the axis 29d.

In the third installation, the table 30 is attached to the wafer transfer device main body 1.
(See Figure 1).

YXex, θy in the above-mentioned clauses (3) and (23)
, fJz axis direction is specifically performed as follows.

Target grooves 21b, 21b, 21b of quartz boat 12
, 21b, 22b, 22b, 22b, 22b sensors 9
．． A computer performs calculations based on position detection results by sensors 9 and 10 and sensors 10 and 10 (not shown). Based on this calculation result, each wheel operating mechanism 31, 31, 32, 33 operates according to instructions from the computer.

The θ2-axis operating mechanism 33 operates, and as described above, in the second installation, the plate 29 rotates in the θ2-axis direction about the axis 29d in FIG. 5B to correctly correct the position in this direction. The Y-wheel operating mechanism 32 operates, and the rail 29c and saddle 2 in FIG.
8c, the first attachment moves the table 28 in the Y-axis direction and correctly corrects the position in this direction. The boat table 4 includes bearings 34, 35, 35 and bearing stands 38.
The first mounting is pivotally supported on the table 28 via the (details will be explained later with reference to FIGS. 6A and 6B).

), and furthermore, the first attachment is attached to the table 28 and is supported by rollers 31a, 31a at the tip of the θXθγ-axis actuator 1I31, which is attached via a plate 28a. Therefore, in the second installation, the position of the boat table 4 is adjusted in both the θ2-axis direction and the Y-axis direction by the correction of the chifur 29 in the θ2-axis direction, and the first installation is the correction of the table 28 in the Y-axis direction. Corrections are made. θXθy axis actuator operating mechanism 3
1 is operated, and the rollers 31a and 31a at the tips of the rollers 31a are raised and lowered, and the boat table 4 is rotated at θ with the bearing 34 as the center.
The ey rotates in the X-axis direction around the bearing 35.35. When both of the exey-axis actuator operating mechanisms 31 move upward, a correction is made in the eyX-axis direction, and when either one moves upward, a correction is made in the eX-axis direction. Thus, by these rotations, the eX-axis direction and ey of the boat table 4
Position correction in the X-axis direction is performed.

Figure 6A shows the boat table 4 and the first installation is table 2.
8 is an enlarged plan view of a portion pivotally supported in a swingable manner, and the figure on day 6 is also an enlarged front view.

In the first installation, a U-shaped bearing stand 39 is fixed to the table 28, a bearing 35.35 is fitted in the bearing stand 39 in the Y-axis direction, and a shaft 37.37 fixed to the bearing holder 38 is fixed to the bearing stand 39. It is rotatably supported on a bearing 35.35. Bearing holder 3
A bearing 34 is fitted to the boat table 8, and a shaft 36 fixed to the boat table 4 is rotatably supported by the bearing 34.

As described above, each wheel operating mechanism 31.31.32.33
4-axis (Y, θX, θy, θ2 axes) position correction unit 80 with the table 28, 29, 30
The first attachment of the boat table 8 is supported by the table 28 so as to be able to swing in three dimensions. Such unitization allows the four-axis position correction unit 80 to be removed from the main body of the apparatus during inspection, repair, or replacement, making these operations easy.

Correction of the position of the boat table 4 in the X-axis direction will be explained later with reference to FIG.

Each wheel actuation mechanism 31, 32, 33 has the structure shown in FIG.

Motor installation is motor 31M (32M, 33M) on stand 41
is attached to the shaft, and a ball screw shaft 40 is attached to the shaft. The shaft 40 is screwed into a socket (nut) 43 of a ball screw through a large number of balls (not shown), and its tip is supported by a bearing 45 fixed to a guide plate 44 . The guide plate is fixed to the motor mounting base 41 via a cylindrical casing 42. One end of a guide shaft 46.46 inserted through the through holes 44a, 44a of the guide plate 44 is fixed to the flange portion 43a of the socket 43, and the other end of the guide shaft 46.46 is fixed to the roller support portion 47.
The roller 3 is fixed to the tip of the roller support part 47.
1a (32a, 33a) are rotatably attached.

The shaft 40 is driven by the motor 31M (32M, 33M).
rotates, thereby causing the socket 43 to move forward and backward. As the socket 43 moves forward and backward, the roller support section 4
The rollers 31a (32a, 33a) attached to the rollers 7 move forward and backward. Since the guide shafts 46 and 46 are guided by the guide plate 44, the direction in which the rollers 31a (32a, 33a) move forward and backward is exactly in the direction of the central axis of each wheel operating mechanism. Note that the guide plate 44 is fixed to the plates 28a, 28a, 29a, and 30a in the installation shown in FIG.

FIG. 8 is a perspective view of essential parts for explaining a mechanism for moving the gripper 7 and lifter 8 in the X-axis direction and a lifting mechanism for the gripper 7. However, each part shown in FIG. 2 is omitted from the illustration so as not to make the drawing too complicated.

In the third installation shown in FIG. 2, a carriage 50 is positioned below the table 30, and a ball screw socket 55 is fixed to the underside of the carriage 50 via a plate 56. Motor 51 fixed to carriage 50
A pulley 52 and a boo IJ5 attached to the shaft 54 of a ball screw screwed into the socket 55 through a number of balls.
A belt (not shown) is attached to the 3 and 3. Thus, the carriage 50 can reciprocate in the X-axis direction by rotating the shaft 54 by driving the motor 51.

The gripper 7 and lifter 8 are attached to the carriage 50 so that they can be displayed, and the motor 51 is driven in response to instructions from the computer based on the calculation results of the computer described above, and the gripper 7 and lifter 8 are positioned in the X-axis direction. corrected,
The gripper 7 and lifter 8 and the quartz boat 12 shown in FIG. 2 are aligned in the vertical direction (X-axis direction). Further, the positions of the gripper 7 and lifter 8 between FIG. 1(a) and FIG. 1(b) are similarly changed by driving the motor 51.

The gripper 7 is raised and lowered by the following mechanism.

An L-shaped support 7a is erected on the carriage 50, and as shown in FIG. 9, which is a sectional view taken along line IX-IX in FIG. 8, U-shaped saddles 65. An L-shaped sliding plate 7f with screws 65 fixed to both ends is engaged so as to be movable up and down. A ball screw socket 63 is fixed to the sliding plate 7f via a socket support plate 64.
The sliding plate 7f moves up and down as the shaft 62 of the ball screw screwed into rotates. The lower end of the shaft 62 has a boo I76.
A belt (not shown) is placed around a pulley 61 and a pulley 60 of a motor 59 fixed to the carriage, so that a shaft 62 is rotated by the drive of the motor 59. An arm support plate 7g is fixed to the upper end of the sliding plate 7f, and the gripping parts 7c, 7c of the gripper are fixed to the arm support plate 7g via the gripping part support 7e and the arm 7b, so that the sliding plate 7f can be moved up and down. Accordingly, the holding parts 7c, 7c move up and down. Note that the left and right clamping parts 7 are attached to the clamping part support 7e.
A mechanism for reducing and enlarging the distances c and 7c is built-in, and the wafer W shown by the imaginary line can be held and released from the holding.

FIG. 10 is a perspective view of essential parts for explaining a mechanism for raising and lowering (moving in the Z-axis direction) the lifter 8 and the sensors 9.9.1o and 10.

The carriage 5o has connecting rods 66, 66, 66 below it.
A plate 67 is fixed to the motor via. For mounting the motor, a plate 73 is located above the plate 67 for mounting the socket, and for mounting the socket, the ball screw socket 7 is located on the plate 73.
2 is fixed. In the figure, 72a is a fixing flange portion of the socket 72. A shaft 71 of a ball screw is screwed into the socket 72, and a pulley 7 attached to the tip of the shaft 71 is screwed into the socket 72.
A belt (not shown) is hung between the pulley 69 of the motor 68 and the pulley 69 of the motor 68. For mounting the socket, the plate 73 is provided with a convex portion 73a having the same height as the socket 72;
A lifter elevating plate 74 and a sensor elevating plate 10c are located above both edges of the sensor 3 in the X-axis direction. The lifter elevating plate 74 has a support rod 75 that passes through the carriage 5o and supports the lifter 8.
75.75.75 is erected, and the support rod 75.75.75.
75 is inserted into a sleeve 76, 76, 76, 76 that stands upright on the carriage 50, and is guided up and down by this. The sensor elevating plate 10c has a support rod 10a that passes through the carriage 50 and has a sensor 10.10 attached to its tip.
10a stands upright, and the support rods 10a, 10a are inserted into sleeves 10b, 10b standing upright on the carriage 50, and are guided up and down by the sleeves 10b, 10b. Sensor lifting plate 10c
The lower ends of the support rods 10a, 10a are fixed to.

For socket installation, the elevation selection plate 78 that slides on the convex portion 73a of the plate 73 is connected to the lifter elevation plate 74 and the sensor elevation plate 10c.
The elevation selection plate 78 is slid in the X-axis direction by a solenoid (not shown) so that the elevation selection plate 78 is located below either the lifter elevation plate 74 or the sensor elevation plate 10c. It is possible.

Driven by the motor 68, the shaft 71 of the ball screw rotates, and the socket 72 that is screwed into the shaft 71 moves up and down. When the elevation selection plate 78 is located below the lifter elevation plates 7 and 4,
As the socket 72 moves up and down, the lifter elevating plate 74 moves up and down, and the lifter 8 moves up and down.

When the elevation selection plate 78 is located below the sensor elevation plate 10c, the sensor elevation selection plate 1
0c moves up and down, and the sensors 10 and 10 move up and down. FIG. 10 shows a state in which the elevation selection plate 78 is located below the lifter elevation plate 74.

This operation of the elevation selection plate 78 can be explained as shown in FIG.
In FIG. 11, which is an X-ray cross-sectional view, a solid line indicates when the elevation selection plate 78 is located below the lifter elevation plate 74, and a solid line indicates when it is located below the sensor elevation plate 10c. is drawn with virtual lines.

The sensor 9.9 is attached to the tips of support rods 9a, 9a that stand on a sensor elevator plate 9c that is different from the sensor elevator plate 10c, and the support rods 9a, 9a penetrate the carriage 50,
It is inserted into sleeves 9b, 9b on the carriage 5o, and guided by the sleeves 9b, 9b when going up and down. carriage 5
An air cylinder 79 is attached to the lower surface of the air cylinder 79 facing downward, and the tip of the piston door 9a of the air cylinder 79 is fixed to the sensor elevating plate 9c. air cylinder 79
The sensor elevating plate is moved up and down by driving, and the sensor 9.9 is moved up and down accordingly.

FIG. 8 shows only the parts necessary for moving the gripper 7 and lifter 8, and FIG. 10 shows only the parts necessary for raising and lowering the beam cover 8 and sensors 9, 10. FIG. 12 is a perspective view of essential parts showing both of the above parts.

The sensor 9.9.10.10 is an analog output non-contact reflective optical sensor, and detects the position of the target groove of the quartz boat by reciprocating and moving up and down in the X-axis direction. The analog output signals from the sensors 9.9.10.10 are converted into digital signals by the A/D converter, and the computer analyzes the digital signals to determine the Y, θX, θy, θ2, and Position correction in the X-axis direction is performed accurately. By using an analog output non-contact reflective sensor, it is possible to detect the roughness of the quartz boat surface, decrease in transparency, and degree of thinning due to hydrofluoric acid, etc. , Y-axis, X-axis, and Z-axis) directions. A reflective sensor with digital output may not be able to detect when the surface of the quartz boat is rough due to cleaning. Further, after the above detection, the position of the quartz boat in the four axes (Y1θX, θy, eZ axes) is corrected accurately by the movement of the boat table, and the position is corrected in the 1st axis (X-axis) direction by the movement of the gripper and lifter. Even if the quartz boat is distorted, it is effective to prevent undesirable dust from being generated and damage to the wafers such as scratches and chips when taking the wafers out of the quartz boat and placing them on the quartz boat. is prevented.

In the above example, the four-axis position correction unit 80 shown in FIG. 2 performs position correction in the four-axis directions of the Y10χ, θy, and ez axes, and the carriage 5o, carriage movement motor 51, and ball screw shaft shown in FIG. 54 and socket 55 to correct the position in the X-axis direction. In contrast, the position correction unit 80 is a five-axis position correction unit, and this position correction unit allows X, Y, θ
It is also possible to perform position correction in the five-axis directions of the x, ey, θ, and Z axes. To do this, for example:
In the first installation shown in FIG. 2, an X-wheel operating mechanism is attached to the table in addition to the 8Xey-axis operating mechanism, and the position is corrected in the X-axis direction using this mechanism. At this time, the third installation is on table 30.
For the second installation, the table 29 is lowered by lowering the table 29 using, for example, a cam mechanism, and the rail 29 in FIG.
(The first attachment is performed by releasing the engagement with the saddle 28c so that the table 28 can move in the X-axis direction.When the above-mentioned engagement is released, the first attachment is performed so that the table 28 does not descend. The first attachment is to the table 28 by suitable support means.
The second attachment is to support the table 29.

Although the present invention has been described in detail above, various modifications can be made to the embodiments described above based on the technical idea of the present invention. For example, it goes without saying that the present invention can be applied to transfer of wafers between a cassette and a quartz boat not only for CVD processing of wafers but also for transfer of wafers for etching and cleaning. . Furthermore, the sensor 9.10 is
In addition to optical sensors, capacitive sensors and ultrasonic sensors can be used. In order to detect the position of the quartz boat, in addition to detecting the target groove, it is also possible to directly detect the wafer insertion groove. Direct detection of the wafer insertion groove allows for more accurate detection. In addition to the wafer, the object to be transferred may be another plate-like object (for example, a glass substrate for a liquid crystal display device, etc.).

1. Effects of the Invention The present invention detects a plurality of locations on the second plate-shaped object mounting member, and based on the detection results, displaces the second mounting member in five directions to place the first plate-shaped object. Since the positional relationship of the second plate-shaped body placement member with respect to the body placement member is matched, even if the second plate-shaped body IF member is distorted and the dimensional accuracy deteriorates, , this deviation in dimensional accuracy is corrected by the above alignment. As a result, the plate-shaped body can be smoothly placed on or taken out from either the first or second plate-shaped body mounting member, and there is no possibility of generating undesirable dust due to rubbing or collision of the plate-shaped body. Damage to the plate-shaped body is reliably prevented and yield is improved.

In particular, in the plate-like object transfer device based on the present invention, at least four-direction displacement means of the five-direction displacement means of the second plate-like object mounting member are combined into a unit. can be easily removed from the main body of the device, and these displacement means can be easily inspected, repaired, and replaced.

[Brief explanation of the drawing]

The drawings all show embodiments of the present invention, and FIG. 1 shows a semiconductor wafer transfer device, and FIG. FIG. 2 is a perspective view of the 4-axis position correction unit, and FIGS. 3 and 4 are perspective views of the 4-axis position correction unit. Figures 5A and 5B are enlarged partial cross-sectional views of the table showing the first and second mountings, respectively; Figure 6A is an enlarged partial cross-sectional view of the table showing the boat table and the first mounting. Fig. 7 is a sectional view of each wheel operating mechanism, Fig. 8 is a perspective view of the main parts of the gripper and lifter movement mechanism in the X-axis direction and the gripper lifting mechanism, and Fig. 9 is a line IX-IX in Fig. 8. Figure 11 is an enlarged cross-sectional view taken along the line XI-XI in Figure 10;
The figure is a perspective view of the main parts of the moving mechanism of the gripper, lifter, and sensor in the X-axis direction and the elevating mechanism thereof. Figure 13 is a plan view of the quartz boat. Figure 14 is a front view of the same. Figure 15 is a side view of the same. , FIG. 16 is an enlarged sectional view taken along the line XVI-XVI in FIG. 13. In addition, in the symbols shown in the drawings, 2...Cassette table 4...
...Boat table 7...Gripper 7c...Gripper clamping parts 7d, 8a,
11a, 21a, 22a...Wafer insertion groove 8...Lifter 9.10...Sensor 9a, 10a... ...Sensor support rod 9C11
0c......Sensor support plate 11...
...Cassette 12...Quartz boat 13...--Quartz boat mounting stand 21.22.
......Bars 21b, 22b of the quartz boat...
......Target groove 28.29.30 ......Mounting mechanism is installed on table 28c, 5
7.65...Saddle 29c, 58...
・・・・・・Rail 31.32.33・・・・・・・・・
・Each wheel operating mechanism 31M, 32M, 33M, 59.68...Motor 40.54.62.71...Pole screw shaft 43.55.63. 72 ......Ball screw socket 50...
... Carriage 74 ... Lifter support plate 75 ... Lifter support rod 78 ... Lifting selection plate 80 ... ...Position correction unit W...
. . . Semiconductor wafer X, Y, θx1θy1θ2 . . . Axes in the position correction direction. Agent Patent Attorney Hiroshi Renkan Figure 3 Figure 4 Figure 5A Figure 5B Figure 8Ej Figure 9 Figure 7 Figure 11 Figure 10 Figure 14 Figure 15

Claims (1)

[Claims] 1. When transferring a plate between a first plate-shaped object mounting member and a second plate-shaped object mounting member, the second plate-shaped object mounting member a step of detecting the positions of a plurality of locations of the second plate-shaped body mounting member based on the detection results; By displacing the first plate-shaped body mounting member in four directions including three circumferential directions centered on the direction of a step of aligning the positional relationship of the second plate-shaped body mounting member, and gripping the plate-shaped body on the first or second plate-shaped body mounting member to place the plate-shaped body on the first or second plate-shaped body. Take it out from the body placement member,
Next, the plate-shaped body is moved relative to the first and second plate-shaped body mounting members and inserted into the second or first plate-shaped body mounting member, and then the plate-shaped body is inserted into the second or first plate-shaped body mounting member. A method for transferring a plate-shaped object, comprising the step of releasing the grip on the plate-shaped object. 2. In a plate-like object transfer device that transfers a plate-like object between a first plate-like object mounting member and a second plate-like object mounting member, the second plate-like object mounting member a position detecting means for detecting the positions of a plurality of places; By displacing the first plate-shaped body in four directions including three circumferential directions centered on three directions orthogonal to the linear direction of the object, and one linear direction orthogonal to the predetermined direction, a positional relationship matching means for aligning the positional relationship of the second plate-shaped object mounting member with respect to the mounting member; Take it out from the first or second plate-shaped object mounting member,
Next, the plate-shaped body is moved relative to the first and second plate-shaped body mounting members and inserted into the second or first plate-shaped body mounting member, and then the plate-shaped body is inserted into the second or first plate-shaped body mounting member. 1. A plate-shaped object transfer device comprising a plate-shaped object gripping means for releasing the grip of the plate-shaped object, and each displacement means for displacing at least the four directions described above is combined into a unit.