JPH03116752A - Wafer housing - Google Patents

Abstract

PURPOSE:To put wafers, which are transferred from a transfer means, without break by equipping a raising-moving means to raise a wafer setting means with a sensor to detect the lowermost groove and raising the wafer setting means on every wafer reception with the lowermost groove on the basis. CONSTITUTION:A shock absorber plate 2 goes forward by operating a switch for housing and at the same time gas is jetted through the gas spout 4-1 of a wafer slider 4. When a wafer 14 is set in the wafer slider 4 with hands, it reaches the elastic body 2' of the shock absorber plate 2. An optical sensor 6 detects the wafer 14 and an air cylinder 13 receives the detection signal, moves back slowly, and can put the wafer in the initial groove 3a of an SiC holder 3 without producing wafer chippings. The gas injection stops simultaneously with the detection of the optical sensor 6.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a wafer storage apparatus, and more particularly to a wafer storage apparatus that sequentially stores processed wafers in each processing process in semiconductor device manufacturing.

[Conventional technology]

As a device of this type, the one shown in FIG. 8 has been known. In the figure, a wafer 52 transferred by a belt conveyor 51 is placed in a wafer holder 53.
It is supposed to move to the side. The wafer holder 53 is made of, for example, tetrafluoroethylene, polypropylene resin,
It is made of aluminum or the like, and has a plurality of grooves 3a formed in its longitudinal direction in which the entire wafer 52 can be accommodated. This wafer holder 53 is placed on a mounting table 54, and this mounting table 54 is raised at every pitch of the groove 3a by a lifting mechanism 56 driven by a lifting motor 55.

[Problems to be Solved by the Invention] However, in the above-described wafer storage device, the wafer holder 53 can be removed from or set on the mounting table 54. Therefore, on the condition that the position setting of the lifting mechanism 56 (especially in the height direction) is sufficiently accurate, the positioning groove 3 is
a must be formed, but in reality it has not been possible to achieve sufficient accuracy.

For this reason, the wafer 52 transferred from the belt conveyor 51 is not smoothly accommodated in the groove 3a of the wafer holder 53, and may collide with the side surface of the wafer holder 53, resulting in damage.

Therefore, the present invention is based on such circumstances, and an object of the present invention is to provide a wafer storage device that can store wafers transferred from a transfer means without damaging them.

[Means to solve the problem]

In order to achieve such an object, the present invention provides a transfer means for transferring wafers one by one, a storage means for storing the wafers transferred from the transfer means, and a lifting means for raising the storage means. The storage means is a member having a semicircular cross section with an opening on the side of the transfer means, and has a groove in its inner wall supporting the periphery of the wafer in a direction perpendicular to the wafer transfer direction on the transfer means. The upward moving means includes a sensor that detects the lowest groove among the grooves arranged in parallel, and the upward moving means includes a sensor that detects the lowest groove among the grooves arranged in parallel, and uses the lowest groove detected by the sensor as a reference. The groove is configured to be raised sequentially by the pitch of the groove each time the wafer is stored.

Further, in such a configuration, the holder is made of quartz glass or charcoal-fired silicon.

Further, the present invention provides a transfer means for transferring wafers one by one, a storage means for storing the wafers transferred from the transfer means, and a storage means for storing the wafers when the wafers are stored in the storage means. The storage means is composed of a member having a semicircular cross section with an opening on the side of the transfer means, and has an inner wall formed around the wafer. The relaxation means is comprised of a holder in which grooves supporting the wafers are arranged in parallel in a direction perpendicular to the wafer transfer direction on the transfer means, and the relaxation means is arranged within a plane containing the wafers transferred from the transfer means and between the storage means. The shock absorber plate is installed on the opposite side to the installation location of the transfer means, and is movable toward the transfer means side through a long hole provided perpendicularly to the groove formed in the holder; The upward moving means includes a sensor that detects the lowest groove among the grooves arranged in parallel, and sequentially moves the wafer by the pitch of the grooves each time the wafer is stored, with the lowest groove detected by the sensor as a reference. It is configured to rise.

[Effect]

In this way, the elevating moving means for elevating the storage means for storing wafers includes a sensor that detects the lowest groove of the holder, and the holder is raised based on the lowest groove detected by the sensor. is taking. Therefore, in the holder, if the grooves are formed at equal pitches, the wafer transferred from the transfer means will be smoothly accommodated in the placement groove of the wafer holder, and will not collide with the side surface of the wafer holder. This eliminates the possibility of defects occurring.

Furthermore, by forming the holder from quartz glass or charcoal silicon, the grooves can be formed at an extremely narrow pitch since the material is hard. This means that a single holder can accommodate as many wafers as possible, making work more efficient.

Moreover, since the holder has a semicircular cross-section, the holder has a configuration in which the contact area with the wafer is minimized, and contamination of the wafer can be prevented.

In addition, since the above-mentioned wafer storage device has a structure in which the entire device is slightly inclined with the transfer means side facing upward, the wafers stored in the wafer holder may come off and drop from the holder. You can eliminate this as much as possible.

In addition, when the wafer is stored in the storage means, direct contact with the storage means can be suppressed by the above-mentioned relaxation means, so even if the holder is made of a hard material, damage to the wafer can be eliminated. I can do it.

〔Example〕

Hereinafter, a first embodiment of the wafer storage device according to the present invention will be described.
This will be explained based on FIGS. 8 through 8. Here, FIG. 1 is an overall configuration diagram of the wafer storage device, and FIG. 2 is a wafer holder (made of silicon carbide) used in the wafer storage device.
3 is a plan view showing the wafer transport means and shock mitigation means used with the wafer storage device; FIG. 4 is a sectional view taken along line A-A in FIG. 3; 5 and 6 are explanatory diagrams of the wafer pickup means of the wafer apparatus, and FIG.
It is a view from arrow B.

First, in FIG. 1, there is a wafer transfer section in which a wafer 14 is transferred in a certain direction a while being floated by a wafer slider 4 having gas ejection holes 4-1.

Also, at the wafer transfer terminal end of this wafer transfer section, S
Mounting table 15 on which iC holder 3 is placed This mounting table 15
A holder pressing member 11 that is attached to and holds the SiC holder 3; an air cylinder 12 that moves the holder pressing member 11; A ball screw 8' for raising and lowering the holder, a pulse motor 8, and an optical sensor 7 for detecting the groove of the SiC holder 3.
There is a holder elevating mechanism consisting of.

Furthermore, the wafer 14 transferred from the wafer slider 4 is placed in the slot 3' of the SiC holder 3 (see FIG. 2).
It moves in the direction shown in the figure. A wafer shock mitigation mechanism is provided which includes a shock absorber plate 2 directly connected to an air cylinder 13.

Further, there is a wafer pickup mechanism consisting of an air cylinder 10 that moves up and down, an air cylinder 9a coupled to the air cylinder 10 that moves horizontally and left and right, and lifting plates 1a and 1b that are attached to the air cylinder 9b and lift up the wafer 14. It is equipped.

The entire device is composed of the above four units and has an inclination angle θ (approximately 15° to 30”).

Next, the structure of the SiC holder 3 will be explained using FIG. 2. The SiC holder 3 has a semicircular cross section, and the groove pitch P on the inner surface is 3/64 inch (1,19
Consists of 100 grooves with a width of 0.6 mm (mm) and a width of 0.6 mm.
Wafers 14 having a thickness of about 0.2 mm can be stored at a precise pitch.

This groove is formed by a special grinding process, and the accuracy of the groove pitch P is ±P and the total groove length D (117,
81mm) is finished with high accuracy, with an accuracy of ±0.05++m or less, and the outer shape is manufactured by sintering. Therefore, the accuracy of the dimension F from the end surface E to the end groove 3b is ensured.

The dimension (F
It is difficult to ensure the dimensional accuracy of H=(F+D) by simply setting the end face E on the mounting table as shown in Figure 8 as an example of the conventional technology, and the dimensional accuracy of H = (F+D) cannot be ensured. The groove 3a in which the wafers are stored does not match the height of the wafers on the belt conveyor, making it impossible to store the wafers.

The operation of the present invention will be explained below.

(1) In Fig. 1, the SiC holder 3 is placed on the mounting table 15.
Set it upward manually. Then, by operating a start switch of a control circuit (not shown), the air cylinder 12
moves forward, and the SiC holder 3 is pressed and held by the holder pressing member 11.

Each operation described below is continuously and automatically operated by a sequence programmer or microcomputer control.

(2) After the above operation is completed (that is, after the air cylinder 12 moves forward), the pulse motor 8 automatically rotates, and the mounting table 15 connected to the ball screw 8' is moved downward (the above-mentioned The air cylinder 12, the holder pressing member 11, and the SiC holder 3 are integrated, and they all move downward.) The end groove 3b of the SiC holder 3 is detected by the optical sensor 7, and at the same time, the rotation of the pulse motor 8 is stopped. be done. As a result, wafer 14
This makes it possible to align the initial groove 3a of the SiC holder 3 in which the wafer slider 3 is initially stored and the 4 surface of the wafer slider. Even in this case, it becomes possible to accurately level the wafers 14 to be stored.

(3) Next, when the storage switch of the control circuit is turned on manually after such an operation is completed, the shock absorber plate 2 passes through the opening 3' of the SiC holder 3 and moves forward by the air cylinder 13. As shown in FIGS. 3 and 4, this shock absorber plate 2 is designed to prevent chipping caused by the wafer 14 to be stored in the forward position colliding with the SiC holder 3.
It is adjusted in advance to stop at a position slightly advanced from the C holder inner surface 3' position.

In addition, an elastic body 2' (for example, made of urethane rubber material) is connected to the tip of the shock absorber plate 2, so that when a collision occurs, all! It has the effect of alleviating force. When the storage switch is operated, the shock absorber plate 2 moves forward, and at the same time, gas (for example, nitrogen gas that has been passed through a filter) is ejected from the gas ejection hole 4-1 of the wafer slider 4, and the wafer 14 is manually removed from the wafer 14. When set on the slider 4, it is transferred in the direction a shown in FIG. 1 and reaches the elastic body 2' of the shock absorber plate 2. When reached in this way, the optical sensor in Figure 3 -
6 detects the wafer 14, and in response to this detection signal, the air cylinder 13 moves slowly backward, and the initial groove 3a of the SiC holder 3 is closed without causing wafer chipping.
can be stored in. Then, the gas jetting also stops at the same time as the optical sensor 6 detects the detection. here,
The optical sensor 5 in FIG. 3 detects the wafer 14 and generates a storage error signal when the wafer 14 is not stored in the SiC holder 3. Therefore, the normal state as shown in FIG. It is attached at a position away from the outer periphery of the stored wafer 14.

(4) Furthermore, as shown in FIG. 1, upon receiving the signal for the end of the backward movement of the air cylinder 13, the control circuit automatically transfers the groove pitch P of the SiC holder 3 to the pulse motor 8.
Count the number of pulses comparable to (1,19+am)
5, that is, the pitch of the SiC holder 3 is raised in accordance with the groove pitch P dimension, and the level alignment between the next groove and the surface of the wafer slider 4 is completed again.

(5) Next, when the storage switch of the control circuit is turned ON again, the wafer pickup mechanism 200 operates.

This process will be explained using FIGS. 5 to 7.

The wafer 14a accommodated in the initial groove 3a has a groove width W (approximately 0
．． 6 mm) and the wafer thickness t' (approximately 0.2 mm), the leading edge of the wafer is tilted forward, which prevents the transfer of the next wafer 14b to be stored. A mechanism for preventing this is the wafer pickup mechanism 20.
It is 0. This is an air cylinder 9a that moves horizontally horizontally in the direction f'f' above the air cylinder 10 that moves up and down in the direction e in the figure.

The block 9 to which the wafer 14a is attached is connected to the air cylinders 9a and 9b, and the lifting plates la and lb for the wafer 14a are assembled to the air cylinders 9a and 9b. First, when the above-mentioned storage switch is turned ON, the air cylinder 10 moves upward.
As shown in FIG. 6, the wafer 14a already accommodated in the groove 3a is lifted up by the lifting plate 1b (and la).

At the same time, gas is ejected from the wafer slider 4.

Also, at this time, the wafer 14 to be stored again is moved manually by the above-mentioned forward movement of the shock absorber plate 2.
When b is set on the 4th side of the wafer slider, it is stored in the groove 3C through the gap δ between the lifting plate 1b (la) and the 4th side of the slider, and is received by the shock absorber plate 2 and moved back in the same way as described above. do. After the shock absorber plate 2 retreats, the air cylinders 9a and 9b of the wafer pickup mechanism 200 move in the f' direction and come off the outer periphery of the wafer 14a, and after the f' operation is completed, the air cylinder 10 moves downward. This f' operation is a means to prevent the wafer 14b located below the wafer 14a from cracking, and the thickness t of the lifting plates 1a and lb is thinner than the groove pitch P and the groove width W of the wafer holder 3. (1<(P-W)). In response to the signal indicating the end of the downward movement of the air cylinder 10, the air cylinders 9a and 9b return to the f' direction, thereby completing the series of operations of the wafer pickup mechanism 200.

(6) Upon receiving such an operation end signal, the operation (4) described above is automatically performed, and the operation (5) described above is repeated again.

(4) The following operations (4) to (5) are repeated, and a counter built into the control circuit calculates that this repeated operation is 10
When the SiC holder 3 is filled with wafers 14, the pulse motor 8 moves the mounting table 1
5 automatically rises to the initial height level, and after completing the rise, the air cylinder 12 moves backward, and the SiC holder 3
will release the hold on it.

In addition, in the series of processes described above, the wafer storage device 1
As shown in Figure 1, 00 itself is at an angle of θ (approximately 15
Since the wafer 14 is tilted at an angle of ~30 degrees, the wafer 14 once stored in the SiC holder 3 does not come out and can be stored stably.

〔Effect of the invention〕

As is clear from the above explanation, according to the wafer storage device according to the present invention, the lifting means for raising the storage means for storing wafers is provided with a sensor for detecting the groove at the lowest end of the holder. The holder is raised based on the detected lowest groove.

Therefore, in the holder, if the grooves are formed at equal pitches, the wafer transferred from the transfer means will be smoothly accommodated in the placement groove of the wafer holder, and will not collide with the side surface of the wafer holder. This eliminates the possibility of defects occurring.

Furthermore, by forming the holder from quartz glass or charcoal silicon, the grooves can be formed at an extremely narrow pitch since the material is hard. This allows a single holder to accommodate as many wafers as possible, thereby increasing the efficiency of one operation.

Moreover, since the holder has a semicircular cross-section, the holder has a configuration in which the contact area with the wafer is minimized, and contamination of the wafer can be prevented.

In addition, since the above-mentioned wafer storage device has a structure in which the entire device is slightly inclined with the transfer means side facing upward, the wafers stored in the wafer holder may come off and drop from the holder. You can eliminate this as much as possible.

In addition, when the wafer is stored in the storage means, direct contact with the storage means can be suppressed by the above-mentioned relaxation means, so even if the holder is made of a hard material, damage to the wafer can be eliminated. I can do it.

[Brief explanation of drawings]

FIG. 1 is an overall configuration diagram of the wafer storage device, FIG. 2 is a diagram showing a wafer holder made of silicon carbide (hereinafter referred to as SiC holder) used in the wafer storage device, and FIG. 3 is a diagram showing the wafer storage device. A plan view showing the wafer transfer means and shock mitigation means used, FIG. 4 is taken from A-A in FIG.
5 and 6 are explanatory diagrams of the wafer pickup means of the wafer apparatus, and FIG.
FIG. 8, which is a view taken along the line B--B in the figure, is a configuration diagram showing an example of a conventional wafer storage device. la, lb...lifting plate, 2...shock absorber plate, 3...SiC
Holder 4... Wafer slider 7... Optical sensor, 8... Pulse motor, 100... Wafer storage device, 200... Wafer pickup mechanism.

Claims (1)

[Claims] 1. A transfer means for transferring wafers one by one; a storage means for storing wafers transferred from the transfer means;
a lifting means for raising the static storage means; the storage means is a member having a semicircular cross section with an opening on the side of the transfer means; The ascending moving means includes holders arranged in parallel in a direction perpendicular to the upper wafer transfer direction, and the upward moving means includes a sensor that detects the lowest groove among the arranged grooves, and the sensor detects the lowest groove. A wafer storage device characterized in that the wafer storage device is configured to sequentially raise the wafer by the pitch of the groove each time the wafer is stored, with reference to the lowermost groove. 2. The wafer storage device according to claim 1, wherein the wafer storage device is slightly inclined as a whole with the transfer means side facing upward. 3. A transfer means for transferring the wafers one by one; a storage means for storing the wafers transferred from the transfer means;
The storage means includes means for relaxing the contact of the wafer against the storage means when the wafer is stored in the storage means, and a lifting means for raising the storage means, and the storage means has an opening on the transfer means side. The holder is made of a member having a semicircular cross section and has grooves on its inner wall that support the circumference of the wafer arranged in parallel in a direction perpendicular to the wafer transfer direction on the transfer means, and the relaxation means A long hole is provided within a plane containing the wafers to be transferred from the means, on the opposite side of the installation location of the forecourt transfer means with the storage means in between, and perpendicular to the groove formed in the holder. It is suitably constituted by a shock absorber plate movable toward the transfer means, and the upward movement means includes a sensor for detecting the lowest groove among the grooves arranged in parallel, and the lowermost groove detected by this sensor. A wafer storage device characterized in that the wafer storage device is configured to sequentially raise the wafer by the pitch of the groove each time the wafer is stored, with the lower end groove as a reference. 4. The wafer storage device according to claim 4, wherein the wafer storage device is slightly inclined as a whole with the transfer means side facing upward.