JPH06333862A - Positioning device for boat in semiconductor manufacturing device - Google Patents

Abstract

PURPOSE:To detect the correct position and to conduct automatic positioning when a boat positioning operation is conducted on a semiconductor manufacturing device, CONSTITUTION:A light-shielding ring 13 is provided on the required position of a boat 5 which is rotatably supported, and a light-transmitting path 14, penetrating the light-shielding ring, is formed on the light-shielding ring. Whether light passes through the boat is detected by the light projector 17, having the optical axis which is coincided with the above-mentioned light-transmitting path, and the light-receiving device 18 which detects the light sent from the light projector, and the boat is positioned by the reception of light by the light receiving device.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a boat positioning apparatus for holding a wafer in a horizontal position in a semiconductor manufacturing apparatus.

[0002]

2. Description of the Related Art In a semiconductor manufacturing apparatus, when a thin film is formed on the surface of a wafer or impurities are diffused, a large number of wafers are held horizontally by boats.

An outline of a semiconductor manufacturing apparatus will be described with reference to FIG.

The reaction furnace 1 is provided at the upper position of the semiconductor manufacturing machine, and the reaction tube 2 is housed inside the reaction furnace 1.
A boat elevator 3 is provided below the reaction furnace 1, and the boat elevator 3 loads and withdraws a boat 5 loaded with a wafer 4 into the reaction tube 2.

The wafer 4 is transferred between the semiconductor manufacturing machine and the outside while being loaded in the wafer cassette 6.
The wafer cassette 6 is relayed by a wafer cassette transfer unit (not shown), then stored in the wafer cassette buffer stocker 7 and the wafer cassette stocker 8 inside, and the wafer cassette stored in the wafer cassette stocker 8 by the wafer transfer machine 9. The wafer 4 of No. 6 is transferred to the boat 5 in the lowered state.

As described above, the boat elevator 3 loads the boat 5 into the reaction tube 2 and takes out the boat from the reaction tube 2 when the film formation of the wafer 4 is completed.

The processed wafer is carried out of the semiconductor manufacturing machine by reversing the above procedure.

In the figure, 10 and 11 are air clean units.

As described above, the wafer 4 is automatically transferred by the wafer transfer machine 9 between the boat 5 and the wafer cassette stocker 8. Therefore, the boat 5 must be accurately positioned with respect to the wafer transfer machine 9. Also, the boat elevator 3 of the boat 5
The mounting on the boat 5 is performed not only for new assembly but also for maintenance such as cleaning of the boat 5.

Conventional boat positioning has been performed as follows.

Positioning pins are provided on the boat receiving surface of the boat elevator 3 so as to project therefrom, and a recess for engaging the positioning pin is provided on the bottom surface of the boat 5, and the recess is engaged with the positioning pin, and then the positioning pin is engaged. The wafer transfer machine 9 was manually operated to transfer the wafers to the boat 5, and final fine adjustment was performed.

[0012]

In the conventional boat positioning described above, there is a problem that it takes a lot of time until the final adjustment, and the mechanical precision of the boat, the etching of the boat by HF cleaning, and the expansion by heating and cooling. The position of the boat may gradually shift due to contraction or the like, but conventionally, there is no means for detecting the boat shift.

In view of the above situation, the present invention is designed so that the position of the boat can be automatically detected and positioned.

[0014]

According to the present invention, a light-shielding ring is provided at a required position of a rotatably supported boat, and a light-transmitting path that penetrates the light-shielding ring is formed in the light-shielding ring. The present invention is characterized in that a light projector having an optical axis that coincides with the light projector and a light receiver for detecting light from the light projector are provided.

[0015]

When the boat is rotated and the light receiver receives the light from the light projector, the position of the boat is matched.

[0016]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

In FIGS. 1 and 2, those having the same functions as those shown in FIG. 3 are designated by the same reference numerals, and the description thereof will be omitted.

In FIG. 1, a light shielding ring 13 is provided at the bottom of the boat 5, and a pair of slits 1 are provided on the diameter line of the light shielding ring 13.
4 is provided so that the light passing through the center of the boat 5 passes through the pair of slits 14.

In FIG. 2, 9 is a wafer transfer machine, and the wafer transfer machine 9 has chuck plates 15 of a required number (for example, 5), and each chuck plate can chuck the wafer 4. There is. The chucking head 16 that holds the chuck plate is rotatable and can move toward and away from the boat 5.

With the chucking head 16 properly facing the boat 5, the chucking head 16
The projector 17 is attached to the boat 5 with the projection optical axis of the projector 17 being
A light receiver 18 is provided on the side opposite to the light projector 17 with respect to the boat 5. Thus, when the slit 14 of the light-shielding ring 13 is aligned with the light projection optical axis of the light projector 17, the light receiver 18 causes the light projector 17 to move.
It is designed to detect the light from.

The boat 5 is installed in the boat elevator 3.
Is provided with a motor 19 for rotating the motor about a vertical axis. The motor 19 is rotated by a motor controller 20, and a motor drive signal from a controller 21 is input to the motor controller 20.

The projector 17 is turned on by the signal from the controller 21 via the driver 23, and the received light signal from the photoreceiver 18 is sent via the signal processor 22 to the controller 2.
Input to 1.

The operation will be described below.

The boat 5 is installed in the boat elevator 3,
The motor 19 is driven by the controller 21 via the motor controller 20 with the chucking head 16 properly facing the boat 5. The motor 19
The boat 5 is rotated by the driving of (1) to generate a state in which the pair of slits 14 are aligned with the optical axis of the projector 17. At this time, the light from the projector 17 is transmitted to the slit 1
4 and reaches the photodetector 18. The light receiver 1
When 8 receives the light, the detection signal from the light receiver 18 is input to the signal processor 22, and the signal processor 22 amplifies the signal from the light receiver 18 and performs A / D conversion, etc.
To enter. The controller 21 stops the motor 19 according to the light receiving signal of the light receiver 18 or stores the rotational position of the boat 5 received by the light receiver 18, and then the motor 1
9 is driven to correct the position.

Thus, the boat 5 can be positioned accurately and quickly.

Although the slit 14 is formed in the light-shielding ring 13 in the above embodiment, a transparent hole may be formed instead of the slit. Further, the slit 14 is provided on the center line of the boat 5 so that the optical axis of the projector 17 passes through the center line of the boat 5, but the optical axis of the projector 17 is displaced from the center of the boat 5. When the boat 5 is rotated once, there is only one transmission position of the projection light beam from the projector 17 when the boat 5 is rotated once. It is convenient.

The light axis of the light projector 17 may be provided so as to pass through the center line of the boat 5, and the center of the boat 5 may be eccentric with respect to the center of rotation of the boat elevator 3.

[0028]

As described above, according to the present invention, the boat can be automatically positioned at the time of mounting the boat without the operator's intuition, the workability is significantly improved, and the positioning accuracy is improved.

[Brief description of drawings]

FIG. 1 is a partial view of a boat used in an embodiment of the present invention.

FIG. 2 is an explanatory diagram showing an embodiment of the present invention.

FIG. 3 is a perspective view showing the outline of a semiconductor manufacturing apparatus.

[Explanation of symbols]

 3 Boat Elevator 5 Boat 9 Wafer Transfer Machine 13 Light-Shielding Ring 14 Slit 17 Emitter 18 Light Receiver 19 Motor

Claims (2)

[Claims] 1. A light projector having a light-shielding ring provided at a required position of a rotatably supported boat, a light-transmitting path penetrating the light-shielding ring being formed in the light-shielding ring, and having an optical axis that matches the light-transmitting path. A boat positioning device in a semiconductor manufacturing apparatus, wherein a light receiver for detecting light from the light projector is provided. 2. The boat positioning device in the semiconductor manufacturing apparatus according to claim 1, wherein the light transmission path formed in the light shielding ring does not pass through the rotation center of the boat.