JPH01282834A - Suction band for shifting wafer - Google Patents

Abstract

PURPOSE:To shift wafers accurately and stably by providing a second pushing means regulated at the reference position of a suction body and a first pushing means pushing the suction body smaller than the second pushing means. CONSTITUTION:Upper sections positioned in the hand body 18 of a suction plate 19 are provided with first and second pushing means 24, 25. The means 25 is furnished while holding the suction plate 19 so as to be oppositely faced to the means 24 on the rear side of the suction plate 19 supplied with the means 24. Stopper sections 31, 32 are installed to the means 25 having large pushing force. Since the means 25 is not retreated by pushing force by the means 24, the means 25 is pushed only by the means 24 when the suction plate 19 is located at a reference position, and the position of the suction plate 19 is not changed even when the unevenness of pushing force is generated in the means 24. Even when a shifting process is repeated, the suction plate 19 is returned to the reference position accurately at all times. Accordingly, wafers can be shifted precisely and stably.

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) The present invention relates to a wafer used when automatically transferring a semiconductor wafer from a carrier for transportation to another holding device such as an electrode plate. Regarding suction hands for transfer.

(Prior Art) Currently, in the process of manufacturing semiconductor chips, devices that directly suction hold and transfer semiconductor wafers are being used. This wafer transfer device is constructed, for example, as shown in FIG.
A suction hand 3 is provided at the tip of the arm 2.

Then, one of the plurality of wafers 5 placed on the carrier 4 is sucked and held by the suction hand 3, and the electrode plate 6 is held by the suction hand 3.
It is scheduled to be transferred to.

Here, the carrier 4 is a holder for transporting a plurality of wafers 5 at once, and the electrode plate 6 is an electrode plate for holding the wafers 5 and performing vapor deposition by plasma CVD method.

The above-mentioned suction hand 3 is constructed as shown in FIG. A hand main body 7 provided at the tip of the arm 2 of the robot 1 is formed into a rectangular box shape, and a suction plate 8 as a sucking body extends from the inside of the hand main body 7.

This suction plate 8 is formed to have a longitudinal direction as shown in FIG. 7, and a suction port 9 as a suction portion is formed on the surface of the tip. This suction port 9 is connected to the suction plate 8.
A communication hole is formed and extended in the suction plate 8 toward the base end thereof, and is opened to the other side at a halfway point. This opening is connected to the suction side of a compressor having a control valve through a tube (not shown). Thereby, the wafer 5 is suctioned onto the surface of the suction plate 8.

The suction plate 8 is supported by the hand main body 7 by a support shaft 10 so as to be able to swing, and the direction of this swing is the direction in which the surface on which the suction port 9 is opened advances and retreats.

In addition, the suction plate 8 located inside the hand body 7 includes:
First and second pressing means 11 and 12 facing each other with the suction plate 8 in between are provided. These pressing means 11.
12 are each formed by coil springs 13, 14 of the same type, and are adapted to press against each other with the same force. Furthermore, two limit switches 15 and 16 are provided on the upper end side of the suction plate 8 for detecting the swinging of the suction plate 8 and operating the drive-side switch.

When the arm 2 of the robot 1 is driven and the wafer 5 held on the carrier 4 is transferred, the suction hand 3 configured as described above first attaches the back side of the suction plate 8 to the edge of the carrier 4. In other words, the back side of the front side where the suction port 9 is opened is brought into contact with the front side as shown in FIG. As a result of this contact, the suction plate 8 is tilted and comes into contact with the limit switch 16 of the two limit switches 15 and 16, which is provided oppositely on the back side. By operating the switch 16, the control device (not shown) of the robot 1 detects the position of the carrier 4, and based on this detected position, the wafer 5 placed on the carrier 4 is held by suction and the electrode plate is Transferred to 6. Note that the suction plate 8 is configured to swing also on the back side, but this is also a relief to prevent damage due to a simple mistake during teaching of work. This escape occurs because the suction plate 8 is made as thin as possible and is easily damaged.

The wafer 5 transfer device described above cannot accurately transfer the wafer 5 unless the suction plate 8 accurately returns to the reference position.

In the devices manufactured to date, the reference position of the suction plate 8 is determined by the balance of the forces of the coil springs 13 and 14. The force balance between these coil springs 13 and 14 is unstable, and if the transfer operation is repeated, the reference position of the suction plate 8 may shift. For this reason, highly accurate positioning may not be possible, and it may not be possible to accurately accommodate and place the device on the carrier 4 or the electrode plate 6.

When the wafer 5 is placed on the electrode plate 6, it is necessary that the wafer 5 be in close contact with the electrode plate 6 as shown in FIG. However, the electrode plate 6 is tilted due to its supported state, making it impossible to transfer the wafer 5 accurately as shown in FIG.

Further, there is a problem that if the wafer 5 is not closely attached to the electrode plate 6, the quality of the silicon nitride film formed during the vapor deposition process will be poor.

Here, it is difficult to adjust the electrode plate 6 to a vertical state, and the electrode plate 6 often tilts to some extent, resulting in the above-mentioned problems. For this reason, the wafer 5 could not be brought into close contact with the electrode plate 6, and it sometimes became impossible to even place the wafer 5 on the electrode plate 6.

Note that the inclination of the electrode plate 6 shown in FIG. 9 is a relatively large inclination for the sake of explanation.

(Problem to be Solved by the Invention) The wafer transfer device uses the same coil spring to press the reference position of the adsorbent from two opposing directions, but the pressing force of the coil spring operates repeatedly. This tends to cause unevenness, and the reference position becomes unstable, making accurate transfer impossible. Furthermore, when placing the wafer on an inclined electrode plate, it may not be possible to place the wafer in close contact with the wafer.

This invention has been made in view of the above problem, and aims to provide a suction hand for transferring wafers that can accurately transfer wafers. An object of the present invention is to provide a suction hand for transferring a wafer that can be positioned accurately.

Another object of the invention is to provide a suction hand for transferring a wafer that can transfer a wafer to an inclined object to be held in close contact with the wafer accurately.

[Structure of the invention]

(Means for Solving the Problems) The invention as set forth in claim 1 is provided with a hand main body, and a suction member having a suction portion formed on the surface thereof for adsorbing a wafer is provided to extend from the hand main body, and the suction a first suppressing means for elastically pressing one side of the body with a predetermined pressing force;
A second suppressing means that presses elastically with a stronger force than the first pressing means is provided to face the first suppressing means with the adsorbent in between, and the pressing force of the second suppressing means is The suction hand for wafer transfer is provided with a regulating means for regulating the suction body at a reference position, and a detection means for detecting movement of the suction body from the reference position.

Further, the invention of claim 2 is provided with a hand main body, an adsorbing member extending from within the hand main body, and an adsorbing portion for adsorbing a wafer on the surface of the extended portion of the adsorbing member, and with the adsorbing member as a reference. A pair of suppressing means are provided facing each other so as to press into position,
A supporting part is provided to support the adsorbent so that the adsorbent can move in an arc in a direction in which the adsorbent is pressed by the pair of suppressing means, and a detection means is provided for detecting that the adsorbent has been moved from a reference position. The wafer transfer device is provided with a tilt drive means for tilting the suction body using the support portion as a fulcrum in a state where the wafer is suctioned and held on the suction portion of the suction body.

(Function) In the invention of claim 1, the first suppressing means is provided on one side of the adsorbent, and the second pressing means is provided on the other side opposite to this, and the first suppressing means is provided on the other side opposite to this. By making the pressing force of the second pressing means larger than that of the pressing means and by providing a regulating means for regulating the pressing force of the second suppressing means at the reference position of the adsorbent, the first and second pressing forces can be reduced. To accurately position an adsorbent at a reference position even if the pressing force is uneven in the means.

According to the second aspect of the invention, by providing a tilt drive means for tilting the suction body when the suction body picks up the wafer, the wafer can be placed accurately even on a tilted object.

(Embodiment) A first embodiment of the present invention will be described with reference to FIGS. 1 and 2. Since the robot arm and the like on which the suction hand 17 is provided are formed in the same manner as conventional ones, Only the configuration of the hand 17 will be explained.

A hand main body 18 of the suction hand 17 shown in the figure is formed into a rectangular box shape, and the upper part of the hand main body 18 is connected to the tip of an arm of a robot (not shown).

Further, a suction plate 19 as a suction body extends from the central portion of the lower surface of the hand body 18 . A midway portion of the suction plate 19 is rotatably supported by the hand main body 18 by a support shaft 20. This suction plate 19 has a suction port 21 opened on the surface of the lower end, and a suction path 22 communicating with the suction port 21 extends inside the suction plate 19 in the longitudinal direction.
It extends to the lower part of the support shaft 20 and is open with a connecting portion 23 on the back side. A compressor is connected to this connection portion 23 via a control valve (not shown). Here, the suction plate 19 is controlled to suction and hold the wafer 5 and to release it by driving a control valve (not shown) by a control device.

On the other hand, first and second pressing means 24 and 25 are provided at the upper part of the suction plate 19 located inside the hand body 18. Among these, the first suppressing means 24 is provided so as to press the upper surface side of the suction plate 19 where the suction port 21 is opened, and is formed by a first coil spring 26 .

The suction plate 1 provided with this first suppressing means 24
A second pressing means 25 is provided on the back side of the holder 9 with the suction plate 19 in between so as to face the first pressing means 24 . This second pressing means 25 is formed by two second coil springs 27.27, and a slide block 28 is coupled to the tips of these second coil springs 27.27. The suction plate 19 is pressed through the suction plate 28. Here, the pressing force of the second coil springs 27, 27 is set larger than the pressing force of the first coil spring 26.

The slide block 28 is connected to the hand main body 1.
The slide block 28 is moved along slide rails 29 and 30 formed integrally with the slide block 8, and serves as a regulating means against which the front end of the slide block 28 comes into contact when the suction plate 19 is at the reference position. Stop portions 31, 32 are formed.

Here, the reference position is the posture position when the suction plate 19 is in a vertical state, for example.

Further, limit switches 33 and 34 are provided at the upper end of the suction plate 19, respectively, and are positioned in the direction of the arc movement by the support shaft 20.

In this way, the first and second pressing means 2 having different pressing forces
4.25, and by providing a stopper portion 31.32 on the second suppressing means 25 with a large pressing force, the suction plate 19
can be accurately biased to the reference position. In other words, since the second biasing means 25 does not retreat due to the pressing force of the first biasing means 24, when the suction plate 19 is at the reference position, it is pressed only by the first suppressing means 24, Even if the first suppressing means 24 has uneven pressing force, the position of the suction plate 19 will not change, so even if the transfer process is repeated, the suction plate 19 will always be accurately placed.
9 is returned to the reference position.

This allows the transfer work to be carried out with high precision. In addition, if the wafers 5,... are not aligned accurately and the suction plate cannot adsorb the wafers and moves in the direction of the wafers 5, the pressing force of the coil spring 13 is set to be weak. , the limit switch can be turned on without breaking the wafer 5.

In the first embodiment, the first and second pressing means 24.25 are the first and second coil springs 26.27.
27, however, the present invention is not limited thereto, and the pressing force of the second suppressing means may be set to be larger than the pressing force of the first suppressing means, and may be constituted by, for example, a leaf spring or the like. Further, although the limit switches 4 and 4 are contact type, a non-contact type may also be used. Furthermore, the suction plate 8
Although it is designed to be able to swing by the support shaft +0, it is not limited to this, and the same effect can be obtained with a mechanism that moves in parallel.

The second embodiment of this invention will be described below with reference to FIGS. 3 and 4.
This will be explained with reference to the figures. Hand body 35 shown in the figure
is provided at the tip of the arm of a robot (not shown), and is formed into a rectangular box shape. A suction plate 36 as a suction body extends from the lower center of the hand main body 35 . This suction plate 36 has a suction port 37 opened on the front side of the lower end, and a suction path 38 communicating with the suction port 37 extends along the longitudinal direction inside the suction plate 36 and is connected to the back side. A portion 23 is formed and opened.

A compressor (not shown) is connected to this connecting portion 23 via a control valve, so that the wafer 5 can be sucked and held on the surface portion where the suction port 37 is opened.

Further, the midway portion of the suction plate 36 is rotatably supported by a support shaft 39 on the hand body 35 side, and the suction plate 36 swings between the front side where the suction port 37 is opened and the corresponding back side. It is designed to move.

Further, the suction plate 36 located above the support shaft 39 is provided with first and second pressing means 40, 41 that press the suction plate 36 between them from the swinging direction. These first and second pressing means 40.41 are connected to two identical types of first and second coil springs 42.4.
3, and the suction plate 36 is supported at the reference position by balancing their pressing forces.

Furthermore, limit switches 44.45 are provided above each of the first and second coil springs 42.43.

Further, in the vicinity of the support shaft 39 of the suction plate 36, a connecting rod 4 connected to a piston 46 as a tilting drive means to be described later.
7 ends are connected. And the piston 46
is provided in a cylinder 48 provided perpendicularly to the suction plate 36 in the reference position, and as the piston 46 moves forward and backward with respect to this cylinder 48, the suction plate 36 is moved in the swinging direction. It is now possible to do so.

A vacuum circuit connected to the compressor (not shown) is connected to the cylinder 48.

By suctioning the wafer, the wafer transfer device configured as described above creates a negative pressure state in the vacuum circuit following the suction path 38, and suctions the piston 46. As a result, when the wafer 5 is held by suction, the suction plate 36
The lower end side of the cylinder 48 is inclined in the direction in which the cylinder 48 is provided.

With this configuration, the suction plate 36 is tilted when the wafer 5 is suction-held, so that, for example, when transferring the wafer 5 from a carrier (not shown) to the electrode plate 6,
The wafer 5 can be tilted and moved relative to the electrode plate 6 and placed so as to come into contact with the support base 49 of the electrode plate 6 from below, so that the lower part of the wafer 5 is first The wafer 5 can be placed in close contact with the electrode plate 6 by bringing it into contact with the corner of the support table 49, and then releasing the suction while moving the suction plate 36 toward the electrode plate 6. can.

By being able to place the wafer 5 from the bottom in this way,
Since the wafer 5 can be brought into airtight contact with the electrode plate 6, it is effective in obtaining a high quality semiconductor wafer 5 when vapor deposition is performed by, for example, plasma CVD. This means that even if the electrode plate 6 is not tilted, the wafer 5 can be stably attached to the electrode plate 6.
can be placed closely together. Furthermore, since the suction force for suctioning and holding the wafer 5 is used, no special driving source is required, and the suction plate 36 is tilted at the same time as the wafer 5 is suctioned, and when the wafer 5 is released, the first Since it returns to the reference position by the pressing force of the coil spring 42, tilting drive can be performed with a simple mechanism.

In the above embodiment, the tilt driving means for tilting the suction plate 36 is shared by the compressor for suctioning the wafer 5 by connecting the cylinder 48 to the vacuum circuit for suctioning and holding the wafer 5. Although the present invention is intended to streamline the structure, the present invention is not limited to this, and any structure may be used as long as the suction plate 36 is tilted while the wafer 5 is suctioned to the suction plate 36.

Furthermore, the suction plate 36 may be tilted only when the wafer 5 is placed on an object to be placed such as the electrode plate 6.

〔Effect of the invention〕

According to the invention of claim 1, the second pressing means is regulated at the reference position of the adsorbent, and the second pressing means is provided opposite to the second pressing means, and the force is smaller than that of the second pressing means. By being pressed against each other by the first suppressing means that presses the suction body, the wafer can be accurately returned to the reference position, and the wafer can be accurately and stably transferred.

Further, according to the second aspect of the invention, by tilting the suction body holding the wafer by suction, the wafer can be accurately placed in close contact with the object to be placed.

[Brief explanation of the drawing]

Figures 1 and 2 show an embodiment of the TJl according to the present invention. Figure 1 is a side sectional view of the suction hand, and Figure 'M2 is the second
Cross-sectional view of the ■-■ line part shown in the figure, Figure 3 and M
4 shows a second embodiment of the present invention, FIG. 3 is a side sectional view of the suction hand, FIG. 4 is a side sectional view of the suction hand with the suction plate in an inclined state, and FIG. 5 is a wafer transfer. 6 is a side sectional view of a conventional suction hand, FIG. 7 is a perspective view showing the structure of the suction plate in cross section, and FIG. 8 is a state in which a wafer is placed on an electrode plate. The instant sectional view shown in FIG. 9 is a side sectional view showing a state in which a wafer is about to be placed on an electrode plate installed at an angle. 18... Hand body, 19... Adsorption plate (adsorption body),
24... First pressing means, 25... Second suppressing means, 31.32... Stopper part (regulating means), 33°3
4... Limit switch (detection means), 35... Hand body, 36... Adsorption plate (adsorption body), 39... Support shaft (support part), 40... First suppression means ( means of suppression)
, 41... second suppression means (suppression means), 44, 45
10. Limit switch (detection means), 46... Piston (tilt drive means), 47... Connecting rod (tilt drive means), 48... Cylinder (tilt drive means). Applicant's Representative Patent Attorney Takehiko Suzue Figure 3 Figure 5 Figure 7 Figure 6 Figure 8 Mother Figure 9

Claims (2)

[Claims] (1) A hand body, a suction body extending from the hand body and having a suction part formed on the surface of the extension part for sucking a wafer, and a suction part of the suction body located inside the hand body. a first pressing means that elastically presses the side surface of the adsorbent with a predetermined pressing force; a second pressing means for elastically pressing with a force stronger than the second pressing means; a pressing force regulating means for regulating the second pressing means at a reference position of the adsorbent; A suction hand for transferring a wafer, characterized in that the suction hand is equipped with a detection means for detecting a wafer transfer. (2) A hand body and a suction body extending from the hand body and having a suction portion formed on the surface of the extension portion for sucking a wafer face each other with the suction body located within the hand body interposed therebetween. a pair of pressing means provided to press the suction body to a reference position; a support portion supporting the suction body so that the suction body can move in an arc in a direction in which the suction body is pressed by the pair of pressing means; The apparatus is characterized by comprising: a detection means for detecting movement of the body; and a tilt drive means for tilting the suction body using the support part as a fulcrum in a state where the wafer is suctioned and held on the suction part of the suction body. Suction hand for wafer transfer.