JPS6127830A - Inversion of carrying direction of substrate and device thereof - Google Patents

Abstract

PURPOSE:To invert the carrying direction of substrate reliably without causing damage by detecting carry-in of substrate to the crossing section of two belts then contacting the substrate against a stopper to be stopped in the center of the crossing section thereafter transferring to the other high carrying face. CONSTITUTION:When carrying a substrate 25 from Y1 direction through crossing section to X1 direction, arrival of substrate 25 to the crossing section is detected through an optical sensor 23 to produce a signal which is used for stopping the drive means 6. The substrate 25 will advance slowly by short distance through inertia then contact against the stopper pins 27, 28 to be positioned approximately in the center of the crossing section. Upon receipt of carrying start signal from X1 direction, an elevating board 15 is functioned to lift the pulleys 9, 10, 16, 19 thus to rise the belts 3, 11 by the height (h) from the carrying face of the belt 2 and to support the substrate 25 on the belts 3, 11. Then the stopper pins 26, 29 are retracted to carry the substrate 25 through the belt 3 in X1 direction.

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to a method for changing the conveying direction of a thin plate material such as a semiconductor wafer, a photomask, or a glass substrate for a liquid crystal display device when conveying the same with a belt. Regarding equipment.

[Prior art]

Conventionally, a device for conveying a substrate with a belt and changing the conveyance direction by approximately 90 degrees in a horizontal plane is disclosed in, for example, U.S. Pat. No. 4,1
It is disclosed in the specification of No. 81,214 or Japanese Patent Application Laid-Open No. 58-48934, and is well known.

In the former method, an optical sensor detects a substrate conveyed from one direction by a first belt, and a second conveyor belt that intersects at right angles to that direction is raised to transport the substrate. This is a device that transfers the first conveyor belt to the second conveyor belt and changes the conveyance direction.

The latter allows the height of the top surface of one of the first and second conveyor belts that intersect with each other to be raised and lowered by ±h relative to the height of the top surface of the other belt. The mounted and transported substrate is, for example, h=1
This is a device that allows the belt to ride on the other crossed belt, which is mm higher.

[Problems with conventional technology]

These conventional techniques have the following problems and disadvantages.

Firstly, since the substrate is not accurately positioned at the belt intersection, guides must be provided close to the substrate on both sides of the conveyance direction after the conveyance direction is changed, and the peripheral edge of the substrate Due to the sliding contact between the substrate and the guide, the periphery of the substrate or the side surface of the guide is scraped, resulting in the generation of dust, which poses problems such as adhesion of dust to the surface of the substrate.

Secondly, there was a risk that the substrate would be damaged when the guide surface came into contact with one substrate.

Thirdly, when the guide corrects the 0 position of the substrate on the conveyor belt, a force is applied to the substrate in a direction perpendicular to the conveyance direction, so there is a gap between the substrate and the belt in contact with the substrate. There have been serious problems such as the belt being removed from the groove of the pulley due to the frictional force of the belt. The purpose is to ensure that the belt is conveyed in the conveyance direction without damage.

[Means for solving problems]

The method of the present invention avoids either one of the conveyor belts so that the two conveyor belts do not come into contact with each other, and transfers the substrate at the intersection of two belt-conveying type conveying means that intersect with each other in the conveying direction. , a stopper that detects that the substrate has been transported to the intersection and stops the transport means and protrudes above the transport surface when transferring from one transport means to the other transport means; By bringing the board into contact with the substrate, the board is stopped accurately at the center of the intersection, and then the transport surface of the other transport means is higher than the transport surface of the transport means supporting the board. The substrate is transferred from one transport means to the other transport means in such a manner that the transport direction of the substrate is changed by driving the other transport means. .

In addition, in order to transfer the substrate from one conveyance means to the other, it is possible to raise the conveyance means on which the substrate is to be transferred, or to lower the conveyance means on which the substrate was being placed. But that's fine.

Further, the apparatus of the present invention includes a first conveyance means for conveying the substrate by a belt conveyance type, a second conveyance means of the belt conveyance type whose conveyance direction intersects with the first conveyance means, and a first conveyance means for conveying the substrate by a belt conveyance type. Second
In order to accurately stop the board at the center of this intersection, there is a detection means for detecting that the board has been transported to the intersection of the transport means. a stopper that protrudes upward and is retracted from the transport surface so as not to impede transport of the substrate; and a stopper that moves the substrate from the first to the second transport means or from the second to the first transport means at the intersection; It is provided with a lifting means that raises or lowers the conveying surface of one conveying means higher or lower than the conveying surface of the other conveying means so that the conveying means can be transferred.

When changing the conveying direction from the first conveying means to the second conveying means, first, the conveying surface of the second conveying means is made lower than the conveying surface of the first conveying means.

When the substrate is conveyed by the first conveyance means and comes to the intersection, the detection means detects that the substrate has reached this position, and stops the driving of the first conveyance means, and also stops the driving of the first conveyance means. contacts the stopper, and the board is positioned at the center of the intersection and stopped.

Subsequently, the stopper is lowered below the conveying surfaces of the first and second conveying means, and the conveying surface of the second conveying means is raised higher than the conveying surface of the first conveying means, and then By driving the second transport means, the transport direction of the substrate is changed.

Note that when changing the conveying direction from the second conveying means to the first conveying means, the conveying surface of the second conveying means is raised in advance so that it is higher than the conveying surface of the first conveying means. Then, the substrate may be stopped at the center of the intersection, and the transport surface of the second transport means may be lowered.

In the method and apparatus according to the present invention, the angle at which the transport directions of the first transport means and the second transport means intersect is generally a right angle in many cases, but is not limited to such an angle, and may also be a cross-shaped angle. It is not limited to an intersection, but may be a T-shaped intersection. At the intersection, at least one of the first and second conveying means,
It may be configured by combining a plurality of divided belt conveyance mechanisms).

These individual belt transport mechanisms may be coupled via associated drive belts, bypassing the other transport belt, or may be provided with individual drive means.

The first and second transport means may transport only in one direction, but if they can transport in both forward and reverse directions, the substrates transported from any direction can be transported in either direction. It's convenient to be able to do it. Further, the conveyor belt may be a plurality of conveyor belts having a circular cross section stretched in parallel, or a single conveyor belt having a wide belt shape.

As the detection means, it is preferable to use a reflection type or transmission type optical sensor from the viewpoint of preventing scratches on the substrate and stabilizing the detection operation, but a microswitch or other sensor may also be used.

Regarding the number and position of the detection means, the detection means may be installed on the sides of the first and second conveyance means from which the substrates are conveyed, or only one detection means may be provided at the center of the intersection. However, if only one board is installed in the center of the intersection, if the sensor detects the board and immediately stops the conveyance means, the basic problem will be:
Since it stops before the center of the intersection, it is necessary to attach a flywheel to the drive shaft etc. to give the conveyance means inertia, or until the time when the sensor detects it and stops driving the conveyance means. All you have to do is set a time lag.

・Also, the timing for stopping the drive of the transport means and when the board contacts the stopper is determined by stopping the drive and
Ideally, the board should be adjusted so that it comes into contact with the stopper when it is moving slowly, albeit a short distance due to inertia, but once the board comes into contact with the stopper, the drive should be stopped. You may also do so.

In the case where the substrate is a semiconductor wafer, for example, the stopper may be a glass mask plate used for printing circuit patterns, etc., and may have 2 to 4 resin pins erected in each transport direction. In some cases, a silicon resin block piece may be used, and there are no particular limitations on its material, shape, and dimensions.

In order to protrude or retract the portion of the stopper that contacts the substrate, it may be attached to the actuating portion using a suitable elevating means such as an air cylinder or an electromagnetic actuator. Alternatively, the stopper may be eccentrically supported and its rotating shaft may be rotated by a required angle to retreat from the conveying surface.

To raise and lower the second conveyance means, for example, an air cylinder or an electromagnetic actuator may be used.
The entire conveying means may be raised and lowered, or only the intersection with the first conveying means may be raised and lowered.

The timing for lowering the stopper and the timing for raising and lowering the second conveying means may be either first or later, or may be simultaneous. Since almost no force is applied to the substrate that has come into contact with the stopper and is stopped, the periphery of the substrate is not scraped by the stopper.

〔Example〕

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

Figures 1 and 2 show an embodiment of the device of the present invention, in which a base (1) is equipped with a set of two conveyor belts (2).
(3) are provided in two sets in the front-rear direction (Yl-Y2) and the left-right direction (XI-X2) so as to intersect with each other.

The first conveyor belt (2) in the Y□-Y2 direction has a pulley (
4) The substrate stretched between (5) and driven by the drive means (6) via the drive belt (7), and placed on the belt (2), is transported in both the front and rear directions. It looks like this.

The second conveyor belt (3) in the Xl-X2 direction (3) is
Pulleys (8) (
9) Drive belt (17) (18,) (20) stretched between and under the conveyor belt (2) (2)
(2)), and is driven by a drive means (12) such as a motor via a drive belt (13).

The pulley (8) is attached to a pair of left and right columns (8a) on the base (1).
) (8a) The pulley (9) on the conveyor belt (2) side, which is pivotally supported at the upper end, is an elevating plate that is moved up and down by a vertical drive means (22) along a guide bar (14) on the base (1). The pulley (10) (16
) is also pivotally supported by a column on the elevating plate (15). - An endless belt (11) for conveyance is wound around the pulley (10), and the endless belt (11) for conveyance is wound between the two first conveyor belts (2) (2) at the same height as the pulley (9). to be located in
It is pivoted at the upper end of a column (10a) erected at the center of the elevating plate (15). Between these pulleys (10) and pulleys (9), a conveyor belt ( 2) below the pulley (16
) (16) is placed.

The lifting plate (15) adjusts the height of the conveying surfaces of the second conveying belt (3) and the endless belt (11) to the height of the conveying surface of the first conveying belt (11).
With respect to the conveying surface of 2), it is possible to switch between a state where the conveyance surface is lower by h (the state shown in FIG. 2) and a state where the conveyor surface is higher by h.

At the intersection of the first and second conveyor belts (2) and (3),
Each is equipped with a reflective optical sensor (23) for detecting the conveyance of the substrate from each direction of X, X2YIY2,
By these optical sensors +j (23), the conveyor belt (2)
(3) and the elevating plate (15) are driven and operated.

First conveyor belt (2) (2) and second conveyor belt (3)
At the intersection of (3), there is a lifting means (Fig. Four stopper pins (26), (27), (28), and (29) attached to the base (not shown) are arranged, and these lifting means are installed on the base (1).

Next, the operation of the apparatus of the embodiment having the above-mentioned configuration will be explained together with the method of the present invention.

First, move the board (25) from the X1 direction through the intersection,
When conveying in the X1 direction, the driving means (6) supplies the substrate (25) placed on the conveyor belt (2) to the intersection from the X1 direction.

The substrate (25) that has reached the intersection is detected by the optical sensor (23), and the driving means (6) is stopped by a signal from the optical sensor (23), and the inertial movement is stopped for a short distance. While moving slowly due to the force, the pair of stopper pins (2) in the X2 direction protruding from the conveying surface
7) Abuts on (28) and is positioned approximately at the center of the intersection.

Next, from the receiving side, that is, from the X1 direction, the board (25
), the driving means (22) such as an air cylinder for the elevating plate (15) is activated, and the pulley (9) is activated.
) (10) (16) Increase (19) by 2h,
The conveyor belt (3) and the endless belt (11) are
- Lift the conveyor belt (2) on the Y2 side higher than the conveyance surface by h. As a result, the substrate (25) that was supported by the conveyor belt (2) is now supported by the conveyor belt (3) and the endless belt (11).

Finally, after recessing the stopper pins (26) and (29) under the conveyance surface, the driving means (12) is driven to drive the substrate (
25) is conveyed in the x-direction by the conveyor belt (3).

Conversely, when conveying the substrate (25) from Xl to X1 direction, the stopper pins (26) (27) are raised in advance, the conveyor belts (3) (11) are lowered,
The substrate (25) may be transferred onto the conveyor belt (2) and conveyed in the Y direction. In this way, the substrate (25) that has been conveyed from a certain direction can be conveyed by changing direction in any direction.

In this embodiment, the substrate (25), if sufficiently larger than the intersection, can move the endless belt (11) to the drive means (12).
Even if the vehicle is idle without being connected to the vehicle, there is no problem in changing direction.

In addition, in order to cope with the case where the dimensions of the board differ for each loft, it is desirable that the position of each stopper pin be adjustable.

FIG. 3 shows an apparatus according to a second embodiment of the present invention, in which the conveyor belt (2) in the Yl-X2 direction is
This device differs from the device of the first embodiment described above in that, like the conveyor belt in the It is.

That is, the intersection side pulley (4) of the conveyor belt (2) in the X1 direction has an endless belt (28
) is wound around the conveyor belt (2) at the same height as the conveyor surface, and is attached to the intersection side pulley (4) of the conveyor belt (2) in the X2 direction.
Similarly, an endless belt (28) is connected to a pulley (27) driven via a drive belt (26).

It is wrapped at the same height as the conveyance surface of the conveyor belt (2).

These pulleys (4) (27) in the Y and -X directions fix their heights on the base (1). On the contrary,
In the Xl-X2 direction, the pulleys (30) interlocked via the intersection side pulley (9) of the conveyor belt (3) in the X1 direction and the X2 direction and the drive belt (29) are both connected to the base ( 1) is lifted and lowered appropriately by the same means as the elevating plate (15) (as shown), and the conveying surface in the x and -X directions is set at a different height with respect to the conveying surface in the Y and -X directions. The conveyance direction of the substrate (25) can be changed to any direction, similarly to the embodiment apparatus shown in the second figure.

In addition, in FIG. 3, the conveyor belt in the X and -X2 directions)
(3) The spaces between (3) may be connected by a drive belt (not shown), or drive means (12) may be provided independently. Conveyor belt in Y, -Y directions (
The same applies to 2).

The apparatus of the invention as detailed above is extremely advantageous, for example, when supplying substrates, such as semiconductor wafers, to automated continuous processing steps.

In other words, in the semiconductor wafer processing process or the glass mask manufacturing process, there is a loader that supplies the substrate from a cassette to the processing process, a buffer for waiting, cleaning, drying, coating, etc. The process consists of a combination of processes, each requiring a different processing time, so the transport path for semiconductor wafers or glass masks must intersect in an extremely complex manner in order to maximize processing efficiency. .

〔Effect of the invention〕

In the present invention, at the intersection of the transport means in two directions, the substrate can be positioned particularly at the center of the intersection by the stopper ratio and temporarily stopped. The substrate can be stably transported by supporting it at the center on both the left and right sides in the transport direction. When transporting a rectangular board with a large difference in vertical and horizontal dimensions, the direction is changed so that the short side of the board is perpendicular to the transport direction.
Particularly effective.

Further, in the present invention, as described above, since the substrate after the conveyance direction has been changed can always be supported at the center of both left and right sides of the conveyance means in the conveyance direction, there is no need to use a guide to correct the position. Therefore, the periphery of the substrate comes into sliding contact with the guide, the periphery of the substrate and the side surface of the guide are scraped, and fine dust does not become attached to the substrate surface, thereby improving the yield.

In addition, in the present invention, the board contacts the stopper, but once the board stops, no further force is applied, so the force is applied continuously around the board, like a guide, until the board is positioned at a predetermined position. There is no possibility that it will be scraped due to sliding contact.

Furthermore, when the substrate position is corrected using a guide, the conveyor belt may come off the groove of the pulley due to the reaction force from the guide, but this does not occur in the present invention because no guide is used.

Furthermore, in the present invention, the work of transferring the substrate from one conveying means to the other conveying means is performed by moving the conveying means up and down while the substrate is stationary, and for example, in contrast to the above-mentioned prior art. Since the operation does not cause the board to ride on the higher side of the crossed conveyor belts, it is natural and the operation is extremely smooth.
It is stable and there is no need to change the board to an inconvenient position.

As can be seen from the two examples, in the present invention, the portion of the conveyor belt that contacts the back surface of the substrate can be prevented from contacting the inner surface of the groove of any pulley, so that the cleanliness of the back surface of the substrate can be maintained. .

As described above, according to the method and apparatus according to the present invention,
When transporting a large amount of substrates between a large number of different processing devices, the substrates can enter the intersection from any direction, and can also be transported in any direction, making the transport route flexible. It is convenient to use in setting layouts and can contribute to improving productivity. In addition, the operation of changing the conveyance direction is stable, and the periphery of the substrate is not scraped and dust is not generated, which can contribute to improving the yield.

[Brief explanation of the drawing]

FIG. 1 is a plan view showing a first embodiment of the device of the present invention, FIG. 2 is a longitudinal sectional view taken along line nn in FIG. 1, and FIG. 3 is a plan view of the device of the present invention. FIG. 7 is a plan view showing a second embodiment.

Claims (8)

[Claims] (1) When transferring the substrate from the first transport means to the second transport means at the intersection of the first transport means and the second transport means whose transport directions intersect with each other, The transport surface of the first transport means is set higher than the transport surface of the second transport means, and when it is detected that the substrate has been transported to the intersection, the drive of the first transport means is stopped. At the same time, the substrate is stopped at the center of the intersection by a stopper previously projected above the transport surface of the first transport means, and the transport surface of the second transport means is lower than the transport surface of the first transport means. Changing the conveying direction of the substrate, characterized in that the conveying direction of the substrate is changed by raising the stopper to a higher position, lowering the stopper below the conveying surface of the second conveying means, and driving the second conveying means. Method. (2) The conveying surface of the first conveying means is kept at a higher level than the conveying surface of the second conveying means by raising the first conveying means, and the conveying surface of the second conveying means is The conveying direction of the substrate according to claim (1), wherein the surface is set higher than the conveying surface of the first conveying means by lowering the first conveying means. Conversion method. (3) The conveyance surface of the first conveyance means is kept at a higher level than the conveyance surface of the second conveyance means by lowering the second conveyance means, and the second conveyance means The substrate according to claim (1), wherein the conveying surface of the substrate is raised to a higher level than the conveying surface of the first conveying means by raising the second conveying means. Conveyance direction change method. (4) Detecting that the board has been transported to the intersection,
Claims (1) to (3), characterized in that the driving of the first conveying means is stopped after the required time has elapsed.
) The method for changing the conveyance direction of a substrate according to any one of the items. (5) A first transport means and a second transport means whose transport directions intersect with each other, a detection means for detecting that a substrate has been transported to an intersection of these transport means, and a detection means that detects that a substrate has been transported to an intersection of these transport means; When the board reaches the center of the section, the front edge of the board in the transport direction comes into contact with it, and when the board enters the intersection,
A stopper that protrudes from the conveying surface and also sinks below the conveying surface during discharge, and at least a first stopper.
Alternatively, an apparatus for changing the direction of conveyance of a substrate, comprising a lifting means for raising or lowering either one of the second conveying means. (6) The first conveyance means consists of a pair of pulleys and two conveyor belts stretched between the pair of pulleys and driven to run in forward and reverse directions, and the second conveyance means , a pair of pulleys arranged on each side of the conveyor belt of the first conveyor means, and a conveyor belt that is tensioned and driven to run in forward and reverse directions for each pair of pulleys arranged in each pair. , at the intersection between the two conveyor belts of the first conveyor means,
Claim No. 1, characterized in that it consists of a pulley rotatably arranged in the same direction as the pulley of the second conveying means (
5) The substrate conveyance direction changing device according to item 5). (7) The elevating means includes a support that pivotally supports each pulley of the second conveying means, which is closer to the conveying belt of the first conveying means, among the pulleys disposed in each pair of the second conveying means; The substrate conveyance direction changing device according to claim 6, characterized in that it is a device that moves up and down an elevating plate that supports a column that pivotally supports a pulley disposed between belts. (8) Claim (5) characterized in that the stopper is eccentrically attached to the rotating shaft, and the stopper is retracted from the conveyance surface by rotating the rotating shaft with a required angular movement. The substrate conveyance direction changing device according to any one of items (7) to (7).