JPH0566021B2 - - Google Patents

Description

[Detailed Description of the Invention] [Object of the Invention] (Industrial Application Field) This invention relates to a wafer used, for example, when automatically transferring a semiconductor wafer from a carrier 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. 5, and includes a suction hand 3 at the tip of an arm 2 of a commonly used robot 1.

Then, one of the plurality of wafers 5 suspended on the carrier 4 is suction-held by the suction hand 3 and transferred to the electrode plate 6.

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 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 suction body extends from the inside of the hand 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. The suction port 9 extends toward the proximal end of the suction plate 8 by forming a communication hole in the suction plate 8, and is opened to the other side surface at a halfway point. This opening is connected through a tube (not shown) to the suction side of a compressor having a control valve. Thereby, the wafer 5 is suctioned onto the surface of the suction plate 8.

The suction plate 8 is attached to the support shaft 1 on the hand body 7.
0 and is 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.

Further, the suction plate 8 located within the hand body 7 is provided with first and second pressing means 11 and 12 facing each other with the suction plate 8 interposed therebetween. These pressing means 11 and 12 are formed by coil springs 13 and 14 of the same type, respectively.
They are designed to press against each other with the same force. Furthermore, the suction plate 8 is provided on the upper end side of the suction plate 8.
Two limit switches 15 and 16 are provided which operate the drive side switch by detecting the swinging of the motor.

When the arm 2 of the robot is driven and the wafer 5 held on the carrier 4 is transferred, the suction hand 3 configured as described above first moves the wafer 5 onto the carrier 4.
At the edge of the suction plate 8, there is a suction port 9 on the back side of the suction plate 8.
The back side with respect to the open front side is brought into contact as shown in FIG. Due to this contact, the suction plate 8 is tilted and comes into contact with the limit switch 16, which is one of the two limit switches 15 and 16, and 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, it attracts and holds the wafer 5 placed on the carrier 4 and attaches it to the electrode plate. 6
Transferred to. 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 as described above has a suction plate 8.
Unless the wafer 5 accurately returns to the reference position, the wafer 5 cannot be transferred accurately.
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 balance of forces between these coil springs 13 and 14 is unstable, and if the transfer work is repeated, the reference position of the suction plate 8 may shift. For this reason, highly accurate positioning is no longer possible, and it has sometimes become impossible 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, as shown in FIG.
It is necessary that the wafer 5 be in close contact with the wafer 5. 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.
There is also 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 it often causes some inclination.
This caused the problems mentioned above. For this reason, the wafer 5 could not be brought into close contact with the electrode plate 6, and could not even be placed on the electrode plate 6. Incidentally, the inclination of the electrode plate 6 shown in FIG. 9 is slightly inclined 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 is Repeated operation tends to cause unevenness, making the reference position unstable and making accurate transfer impossible. Further, when placing the wafer on an inclined electrode plate, it sometimes became impossible to place the wafer in close contact with the wafer.

This invention has been made in view of the above-mentioned problems, 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 holding object so as to accurately and closely contact the wafer.

[Structure of the invention]

(Means for Solving the Problems) The invention as set forth in claim 1 is provided with a hand main body, a suction member having a suction portion formed on its surface for suctioning a wafer, extending from the hand main body, and A first pressing means for elastically pressing one side of the body with a predetermined pressing force is provided, and a second pressing means for elastically pressing with a stronger force than the first pressing means is provided on the adsorbent. A regulating means is provided so as to sandwich and face the first pressing means, and regulates the pressing force of the second pressing means at a reference position of the adsorbent, and detects that the adsorbent has moved from the reference position. A suction hand for transferring a wafer is equipped with a detection means for detecting the wafer.

In addition, 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 pressing means are provided facing each other so as to press the adsorbing member into a position, and a supporting portion is provided to support the adsorbing member so that the adsorbing member can move in an arc in the direction in which the adsorbing member is pressed by the pair of pressing means. A wafer is provided with a detection means for detecting that the body has been moved from a reference position, and an inclination driving 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. on the transfer equipment.

(Function) In the invention of claim 1, the first pressing 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 pressing 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 pressing 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. Only the configuration of the hand 17 will be explained.

The hand body 18 of the suction hand 17 shown in the figure is formed into a rectangular box shape.
The upper part of the robot 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 . The middle part of this adsorbent 19 is attached to the support shaft 2 on the hand main body 18.
It is rotatably supported by 0. 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 and extends under the support shaft 20. It is extended up to 300 degrees and has a connecting portion 23 and an opening on the back side. A compressor is connected to this connecting 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, the upper part of the suction plate 19 located inside the hand body 18 has first and second pressing means 24,
25 are provided. Of these, the first pressing 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 .

A second pressing means 25 is provided on the back side of the suction plate 19 on which the first pressing means 24 is provided, with the suction plate 19 interposed therebetween so as to face the first pressing means 24. ing. This second pressing means 25 is formed by two second coil springs 27, 27, and a slide block 28 is provided at the tip of these second coil springs 27, 27.
are connected to each other, and the suction plate 19 is pressed through this slide block 28. here,
The pressing force of the second coil springs 27, 27 is the same as that of the first coil spring.
The pressing force of the coil spring 26 is set larger than that of the coil spring 26.

The slide block 28 has a slide rail 2 integrally formed with the hand main body 18.
9 and 30,
Stopper portions 31 and 32 are formed as 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. Here, the reference position is the posture position when the suction plate 19 is, for example, in a vertical state.Furthermore, at the upper end of the suction plate 19, there are respectively positioned in the direction in which the suction plate 19 can move in an arc by the support shaft 20. Limit switches 33 and 34 are provided.

By providing the first and second pressing means 24 and 25 with different pressing forces and providing the stoppers 31 and 32 on the second pressing means 25 with a larger pressing force, the suction plate 19 can be moved to the reference position. Biasing can be performed accurately. 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 pressing means 24. Therefore, even if the first pressing 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 positioned. It is returned to the standard position.
This allows the transfer work to be carried out with high precision. Also, if the wafers 5,... are not aligned accurately, the suction plate may not be able to suction the wafers, and the wafers 5,...
If you continue in the same direction, the coil spring 13
Since the pressing force is set to be weak, the limit switch 33 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, but the present invention is not limited to this. The pressure may be set to be larger than the pressing force of the first pressing means, and may be formed of, for example, a leaf spring. In addition, limit switch 33,
34 is a contact type, but a non-contact type may also be used. Furthermore, although the suction plate 8 is designed to be able to swing by the support shaft 20, the present invention is not limited to this, and the same effect can be obtained with a mechanism that moves in parallel.

A second embodiment of the present invention will be described below with reference to FIGS. 3 and 4. The hand main body 35 shown in the figure is provided at the tip of an 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 this 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 connection 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.

In addition, the middle part of the suction plate 36 is connected to the hand main body 3.
The suction plate 36 is rotatably supported on the 5 side by a support shaft 39, and is configured to swing between the front side where the suction port 37 is opened and the corresponding back side.

Further, the suction plates 36 located at the upper part of the support shaft 39 are arranged so that the suction plates 36 are mutually attached to each other from the swinging direction.
The first and second pressing means 4 sandwich and press 6.
0,41 are provided. These first and second pressing means 40, 41 consist of two identical type first and second coil springs 42, 43,
The suction plate 36 is supported at the reference position by balancing the mutual pressing forces.

Furthermore, the first and second coil springs 4
Limit switches 44 and 45 are provided above each of 2 and 43, respectively.

Further, in the vicinity of the support shaft 39 of the suction plate 36, an end portion of a connecting rod 47 connected to a piston 46 serving as a tilt driving means, which will be described later, is connected. Then, the piston 46 is moved to the suction plate 3 at the reference position.
Cylinder 4 provided perpendicular to 6
The suction plate 36 can be moved in the swinging direction by moving the piston 46 forward and backward with respect to the cylinder 48.
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 lower end side of the suction plate 36 is tilted in the direction in which the cylinder 48 is provided.

With this configuration, the suction plate 36 is tilted while holding the wafer 5 by suction.
For example, when transferring the wafer 5 from a carrier (not shown) to the electrode plate 6, the wafer 5 is moved while being tilted with respect to the electrode plate 6, and the wafer 5 is placed under the support base 49 of the electrode plate 6. Since the wafer 5 can be placed in contact with it from the side, the lower part of the wafer 5 can be brought into contact with the corner of the support table 49 first, and then the suction is released while the suction plate 36 moves toward the electrode plate 6 side. This allows the wafer 5 to be placed in close contact with the electrode plate 6.

By being able to place the wafer 5 from below in this way, the wafer 5 can be brought into airtight contact with the electrode plate 6, which is effective in obtaining high-quality semiconductor wafers 5 when vapor deposition is performed by, for example, plasma CVD. It is. This allows the wafer 5 to be stably placed in close contact with the electrode plate 6 even when the electrode plate 6 is not tilted. Furthermore, since the suction force for suctioning and holding the wafer 5 is used, a special driving source is not 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 is designed to return 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 pressing means that presses the suction body, the wafer can be accurately returned to the reference position, and accurate and stable transfer of the wafer can be made possible.

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

[Brief explanation of the drawing]

1 and 2 show a first embodiment of the present invention, in which FIG. 1 is a side sectional view of the suction hand, FIG. 2 is a sectional view of the portion indicated by the line - in FIG. and FIG. 4 is the second diagram in this invention.
This is an example, and FIG. 3 is a side sectional view of the suction hand.
Figure 4 is a side sectional view of the suction hand with the suction plate in an inclined state, Figure 5 is a perspective view of the wafer transfer device, Figure 6 is a side sectional view of the conventional suction hand, and Figure 7 is the suction plate. Fig. 8 is a cross-sectional view showing a state in which a wafer is placed on an electrode plate, and Fig. 9 is a perspective view showing a state in which a wafer is placed on an electrode plate installed at an angle. It is a side sectional view showing a state. 18...Hand body, 19...Adsorption plate (adsorption body),
24...first pressing means, 25...second pressing means,
31, 32...Stopper part (regulating means), 33, 3
4... Limit switch (detection means), 35... Hand main body, 36... Adsorption plate (adsorption body), 39... Support shaft (support part), 40... First pressing means (pressing means),
41...Second pressing means (pressing means), 44, 45
...Limit switch (detection means), 46...Piston (tilt drive means), 47...Connecting rod (tilt drive means), 48...Cylinder (tilt drive means).

Claims (1)

[Scope of Claims] 1. A hand main body, a suction member extending from the hand main body and having a suction portion formed on the surface of the extension portion for adsorbing a wafer, and a suction body located within the hand main body. a first pressing means that elastically presses the side surface on which the suction portion is provided with a predetermined pressing force; a second pressing means that presses elastically with a stronger force than the first pressing means;
A wafer transfer device characterized by comprising a pressing force regulating means for regulating the second pressing means at a reference position of the suction body, and a detection means for detecting that the suction body has moved from the reference position. Suction hand for mounting. 2. A hand main body, a suction member extending from the hand main body and having a suction portion formed on the surface of the extension portion for adsorbing a wafer, and facing each other with the suction body located within the hand main 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.