JPH0311099B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Object of the Invention] (Industrial Application Field) The present invention relates to a method for storing trays in a wafer transport device that transports wafers for etching processing.

(Prior art) Generally, for etching processing of a wafer, the wafer is placed in a load lock chamber, then etched in a vacuum chamber, the processed wafer is transferred to an unload chamber, and then taken out into the atmosphere. ing.

In this way, wafers need to be transported according to a certain procedure for the etching process, but conventionally, each wafer is put into the processing chamber individually, so there is a risk of contamination or damage to the electrodes due to etching products in the processing chamber. There were problems such as damage.

Therefore, as of November 22, 1985, the applicant proposed a wafer feeding device that transfers unprocessed stacked wafers one by one, and a wafer feeding device that once receives the fed wafers and places them on a predetermined position on a tray. a mounting device, a first wafer transport device that transports a tray on which a wafer is mounted to a wafer processing chamber, a second wafer transport device that transports a processed wafer together with the tray, and the second wafer transport device. A wafer separating device picks up the processed wafers sent from the tray, a wafer storage device stacks and stacks the processed wafers picked up from the tray, and a wafer storage device connects the wafer mounting device and the wafer separating device to connect the two devices. proposed a wafer transport device consisting of a tray transport device for transporting trays.

(Problems to be solved by the invention) However, in such a wafer transfer device,
Since the tray is brought into the vacuum processing chamber, there is a problem that if the tray is left in the atmosphere due to the influence of the gas used in the vacuum processing chamber, the tray will corrode due to the influence of the gas adhering to the tray.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a method for effectively preventing corrosion of the tray in an apparatus in which wafers are processed on a tray.

[Structure of the invention]

(Means for Solving the Problems) The present invention provides a wafer feeding device that transfers stacked wafers one by one before processing, and a wafer feeding device that once receives the fed wafers and places them on a predetermined position on a tray. A loading device, a first wafer transfer device that transfers the tray on which the wafer is placed to the wafer processing chamber via the load lock chamber, and a second wafer transfer device that transfers the processed wafer together with the tray via the unload lock chamber. a wafer separation device that picks up the processed wafers sent by the second wafer transfer device from the tray; a wafer storage device that stacks and stacks the processed wafers picked up from the tray; and the wafer placement device and the wafers. A tray transport device is provided that communicates between the separation devices and transports the tray between both devices, and at least one of the trays is circulated between the wafer loading device, the load lock chamber, the wafer processing chamber, the unload lock chamber, and the wafer separation device. Furthermore, when the apparatus is not in use, the tray is stored in a vacuumed load lock chamber, wafer processing chamber, or unload lock chamber.

(Function) When the tray is stored in a vacuumed load lock chamber, wafer processing chamber, or unload lock chamber when the apparatus is not in use, corrosion of the tray due to reaction gas adhering to the tray can be effectively prevented. .

(Example) Hereinafter, an example of the present invention will be described with reference to the drawings.

In FIGS. 1 and 2, a chamber R ₁ at atmospheric pressure is provided with a wafer W feeding device 1 that stacks unprocessed wafers W and feeds out one wafer W one after another, and the wafers sent from this feeding device 1 are W is sent to the wafer mounting device 2 provided in the adjacent room _R2 . The chamber _R2 is also at atmospheric pressure, and the wafer mounting device 2 is for mounting the wafer W sent from the feeding device 1 at a predetermined position on the tray. The wafer W placed on the tray is transported to the load lock chamber R3 by the wafer transport device ₃ ,
It is further turned around and transported to vacuum processing chamber _R4 .

The wafer W that has been etched in the processing chamber _R4 is transferred to the unloading lock chamber _R5 by the transfer device 4.
The separated wafers W are transferred to a wafer separation device 5 provided in the chamber for separating processed wafers from the tray, and the separated wafers W are transferred to a wafer storage device 6 in a chamber _R6 .
Then, the tray from which the wafers have been removed by the wafer separating device 5 is transferred to the wafer mounting device 2 by the tray conveying device 7.

As shown in FIGS. 2 and 3, the feeding device 1 has wafer carriers 11a and 11a placed on carrier stages 10a and 10a, which are spaced apart from each other on the left and right sides. Wafers W are stacked one above the other in 11a. A frame 1 is provided at the center of the carrier stage 10a.
2a, and two pairs of conveyor belts 13a, 13a are provided on the left and right sides of this frame 12a, and the wafer carrier 11 is conveyed by this conveyor belt 13a.
The wafer W located at the lowest position in a is sequentially sent to the wafer mounting device 2.

The wafer mounting device 2 includes a pair of support devices 14a, 14a that support the wafer opened and closed to the left and right on the same plane as the frame 12a, and each support device 14a has a horizontal support plate 15, as shown in FIG.
a, and a conveyor belt 16a provided on the inner end surface of the horizontal support plate 15a.
a is held horizontally by a vertical frame 17a, which is connected to the drive screw 1.
8a, and by rotating this drive screw 18a, the pair of left and right support devices 14a open and close left and right along the guide 19a.

A wafer lifting device 20a having a shape as shown in FIG. 5 is provided below the supporting device 14a, and a tray lifting device 21a is installed outside of this wafer supporting device 20a. Both these devices 20
a, 21a are U-shaped frames 22a, 23a, support pins 24a, 25a erected on these frames,
It consists of drive cylinders 26a and 27a that move these frames 22a and 23a up and down. The support pins 24a of the wafer lifting device 20a are inserted into the through holes 28, 2 of the center support portion 27 of the tray T as shown in FIG.
8, . . . 28, and a wafer W is placed on the center support portion 27 of the tray T (FIG. 7).

A wafer positioning device 30a is provided in the vicinity of the support device 20a on substantially the same plane,
The wafer positioning device 30a is configured to fit under the wafer W and support it when the pair of supporting devices 20a are open, and rotate the wafer W by a predetermined angle to align it with the orientation flat corresponding position of the tray T. Position. The wafer positioning device 30a includes a support rod 31a that moves horizontally, and a rotary table 3 that is supported by the support rod 31a and rotated by a motor.
2a, and a sensor 33a that detects the position of the wafer W.
This sensor 33a causes the rotary table 32a to stop when the orientation flat of the wafer is aligned with the position corresponding to the center support portion 27 of the tray T.

The wafer W placed on a predetermined position on the tray T by the wafer placement device 2 is transported together with the tray T to the load lock chamber R3 by a carrier ₃ as shown in FIGS.

That is, an outer rotating shaft 105 is rotatably attached to the center of the bottom of the load lock chamber, passing through the bottom, and a central rotating shaft 106 is rotatably inserted concentrically into the outer rotating shaft 105. has been done. A fixed wheel 1 is arranged concentrically above the load lock chamber _R3 of the outer rotating shaft 105.
07 is fixed, and a support plate 10 is attached below the support plate 10.
8 is fixed. The upper end of the central rotating shaft 106 protrudes from the outer rotating shaft 105, and the first arm 100 is attached to the upper end, and the first arm 100 is attached to the supporting plate 108.
Another first arm 100 is rotatably attached symmetrically to the first arm 100. Each of these first arms 100,1
At the center of rotation of 00, there are gears 10 that mesh with each other.
9,109 are attached, and the central rotating shaft 106
The first arms 100, 100 are rotated symmetrically by the rotational drive of the first arms 100, 100. Further, a second arm 1 having gears 110, 110 attached to the tip end of each of the first arms 100, 100.
02, 102 are respectively rotatably attached, and each second arm 102, 102 is rotatably connected to the tip of each of these second arms 102, 102 so that the gears 110, 110 mesh with each other. A mounting plate 103 for wafers is provided. Further, a rotating wheel 111 is attached to the lower end of the rotating shaft of one of the second arms 102, and a belt 112 is hung between the fixed wheel 107 and the rotating wheel 111. The diameter ratio is 2:1. Furthermore, a motor 113 for rotating the central rotating shaft 106 and a motor 115 for rotating the outer rotating shaft 105 via a belt 114 are provided on the lower surface side of the chamber 104, respectively.
A ball screw 116 serving as an elevating drive device is screwed onto the outer rotating shaft 105.

In this embodiment, as shown by the solid line in FIG. 9, a state in which the center of the mounting plate 103 is approximately located at the center of the outer rotating shaft 5 is considered to be a standby state (stationary state), and the center rotating shaft 106 is connected to the motor. 113, each of the first arms 100, 100 rotates symmetrically, and the belt 112 rotates the rotary wheel 111, so that each of the second arms 102, 1
02 rotates in the opposite direction to the first arms 100, 100, and the movement of these arms 100, 102 causes the mounting plate 103 to move linearly. When rotating the device, drive the motor 115 in the above-mentioned standby state to rotate the outer rotating shaft 1 at a predetermined angle.
05 together with the support plate 108. Thereby, the wafer and tray can be transferred to the vacuum processing chamber.

The wafers processed in the vacuum wafer processing chamber _R4 are transported together with the tray T to the unloading lock chamber _R5 by a carrier 40a as shown in FIG. The conveyor 40a includes a tray stand 41a, a support frame 42a, and rollers 43a, and the rollers 43a roll on rails 44a. Also, the tray T transported by the transport device 4
The processed wafer W is processed by a wafer separation device 5 that separates the wafer W from the tray T.
This wafer separating device 5 has almost the same structure as the wafer mounting device 2 described above. That is, a pair of support devices 14b, 14b, a conveyor belt 16b provided inside this support device 14b, and a guide 19.
b. Wafer lifting device 20 of the wafer mounting device 2
a, a wafer lifting device 20b provided opposite the tray lifting device 21a, and a tray lifting device 21
b, and further includes drive cylinders 26b and 27b. The wafer lifting device 20b includes a U-shaped frame 22b and support pins 24b, 24b, . . . 24.
b, and the tray lifting device 21b has a U-shaped frame 23b and support pins 25b, 25b, . . . 25
It has b.

A tray conveying device 7 is provided between the two wafer supporting devices 20a and 20b, and this device 7 consists of a rail 50 and a conveying body 51 that moves on the rail, and this conveying body 51 has rolling rollers 52. There is.

A wafer storage device 6 provided adjacent to the wafer separating device 5 has a structure similar to that of the feeding device 1, and processed wafers W are stacked one by one. The wafer storage device 6 is a carrier stage 1.
0b, 10b, wafer carrier 11b, 11b,
Frame 12b and conveyor belts 13b, 13b
have.

The unprocessed wafer W on the feeding device 1 is sent by a conveyor belt 13a onto a pair of support devices 14a spaced apart from each other so as to support both end portions of the wafer W. At this time, the tray T is on the carrier 51 of the tray carrier 7 located inside the wafer mounting device 2, as shown in FIG. Next, the drive cylinder 26a is connected to the wafer lifting device 20a.
lift up. At this time, the support pins 24a penetrate upward through the through holes 28 of the tray T and float the wafer W above the support device 14a. In this state, the wafer positioning device 30a enters under the wafer W, and at the same time the supporting device 1
4a opens. Next, the support pins 24a are slightly lowered, and the wafer W is placed on the rotary table 32a. The rotary table 32a rotates, and the sensor 33a
When detecting the orientation flat of the wafer W, the rotary table 32a stops.

After that, the support pin 24a rises again and the wafer W
The wafer positioning device 30a is lifted from above the rotary table 32a, and the wafer positioning device 30a is returned to the standby position. Next, the support pins 24a are lowered greatly to lower the wafer W.
is placed on the carrier 51 at a position aligned with the center support portion 27 of the tray T.

Next, the tray lifting device 21a is raised to lift the tray T slightly above the conveyor 51. In this state, the carrier 51 is moved to the wafer lifting device 20b side of the wafer separating device 5 to receive an empty tray, and at the same time the mounting plate 103 of the carrier 3 is moved to the lower side of the tray T. Lifting device 21
a is lowered to place the tray T on the placing plate 103. In this way, the wafer W placed on the tray T is transferred to the load lock chamber _R3 , and further transferred to the processing chamber _R4 , where it is subjected to vacuum processing.

The vacuum-processed wafer W is transferred onto the carrier 40a, and this carrier 40a enters the wafer separation apparatus. Next, the tray lifting device 21b is raised to lift the tray T, and in this state, the transport body 40
Return b to its original position. Next, the wafer lifting device 2
0b is raised to lift the wafer W above the support device 14b. At this time, the support device 14b is open so that the wafer W can pass through, and when the wafer W passes upward, the support device 14b
When the distance b becomes narrower and the wafer lifting device 20b descends, both end portions of the wafer W are lifted up by the wafer support device 14.
It is placed on b. When the lowering of the wafer lifting device 20b is completed, the carrier 51 enters into the wafer lifting device 20b. Next, the tray lifting device 21b is lowered to place the empty tray T on the carrier 51, and the empty tray T is sent into the wafer carrier 2. The processed wafer W is transferred to the conveyor belt 16
The wafer is sent onto the wafer storage device 6 by the drive of the wafer b.
This operation is repeated one after another, and the tray T moves as indicated by arrow A in FIG.

Three trays T are normally used, and these trays T are circulated through each chamber in sequence. When the device is not in use, each tray T is transferred to the wafer transfer devices 3 and 4.
Then, the tray transfer device 7 is operated to store the trays in the load lock chamber R ₃ , wafer processing chamber R ₄ , and unload lock chamber R ₅ in a vacuum state. Furthermore,
When starting the operation of the apparatus, empty trays T are sequentially taken out of the vacuum chamber and wafers are placed on them.

〔Effect of the invention〕

Since the present invention is configured as described above, it is possible to effectively prevent corrosion of the tray T due to the influence of the reaction gas.

[Brief explanation of the drawing]

FIG. 1 is a schematic overall configuration diagram of this device, FIG. 2 is a schematic overall plan configuration diagram of this device, and FIG. 3 is a side view of the same.
FIG. 4 is a perspective view of the wafer support device, FIG. 5 is a perspective view of the wafer lifting device, and FIG. 6 is a plan view of the tray.
7 is a side view of the tray, FIG. 8 is a front view of the wafer transfer device, FIG. 9 is a plan view thereof, and FIG. 10 is a perspective view of the wafer transfer device. DESCRIPTION OF SYMBOLS 1...Wafer feeding device, 2...Wafer mounting device, 3, 4...Wafer transfer device, 5...Wafer separation device, 6...Wafer storage device, 7...Tray transfer device, 20a, 20b... ...Wafer lifting device, 21a, 21b...Tray lifting device.

Claims (1)

[Claims] 1. A wafer feeding device that transfers the stacked wafers one by one before processing, a wafer mounting device that receives the fed wafers and places them on a predetermined position on the tray, and a tray on which the wafers are placed. A first wafer transport device transports the processed wafer to the wafer processing chamber via the load lock chamber, a second wafer transport device transports the processed wafer together with the tray through the unload lock chamber, and the wafer is transported by the second wafer transport device. A wafer separation device that picks up processed wafers from the tray, a wafer storage device that stacks the processed wafers picked up from the tray, and a wafer storage device that communicates between the wafer placement device and the wafer separation device and transports the tray between both devices. A tray conveying device is provided,
at least one of the trays is a wafer mounting device;
The tray is circulated between a load lock chamber, a wafer processing chamber, an unload lock chamber, and a wafer separation device, and when the device is not in use, the tray is stored in one of the load lock chamber, wafer processing chamber, and unload lock chamber in a vacuum state. A tray storage method for a wafer transfer device characterized by the following: