JPS6214693Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a wafer transport device, and particularly to an improvement of a wafer transport device suitable for semiconductor manufacturing equipment that determines the presence or absence of a wafer using a photodetection method.

In the processing chamber of semiconductor manufacturing equipment that uses conventional optical detection methods to determine the presence or absence of wafers, there are rotating electrodes with light passage holes drilled at multiple wafer placement positions (hereinafter referred to as placement positions). possible internally,
Further, a light emitting element and a light receiving element are provided coaxially with the light passage hole of the electrode. In addition, a wafer gripping means (hereinafter abbreviated as gripping means) such as a mechanical chuck or a vacuum chuck is installed in a preliminary chamber provided in the processing chamber.
A wafer transfer arm (hereinafter simply referred to as arm) provided with a wafer transfer arm is provided therein so as to be movable in a straight line or partially rotated so as to allow the gripping means to reach the electrode placement position from the preliminary chamber.

The presence or absence of a wafer at the electrode mounting position is determined by whether or not the light emitted from the light emitting element is received by the light receiving element. It is grasped by the arm and transported by moving the arm straight or partially rotating.

In such semiconductor manufacturing equipment, when the gripping device reaches the electrode placement position due to straight movement or partial rotation of the arm or rotation of the electrode, the light emitted from the light emitting element will move forward depending on whether there is a wafer or not. Regardless, it is blocked by the gripping means and the presence or absence of the wafer cannot be properly determined. Therefore, the gripping means that has reached the electrode placement position can be temporarily moved from the electrode placement position by moving the arm straight or by partially rotating the arm. The disadvantage is that the overall wafer transport time becomes longer and the throughput decreases.

An object of the present invention is to provide a wafer transfer device that can shorten the overall wafer transfer time and improve throughput by eliminating the drawbacks of the prior art described above.

The present invention includes a light emitting element and an optical axis of light from the light emitting element in a wafer gripping means for gripping and transporting a wafer between a wafer placement position of an electrode rotatably installed in a processing chamber and a preliminary chamber. A light passing window provided in the processing chamber corresponds to a light receiving element provided above, and a light passing hole is formed at a wafer mounting position of the electrode so as to correspond to the light passing window. This device is characterized by having a light passage hole that can pass through the electrode, and it is possible to appropriately determine the presence or absence of a wafer without once shifting the gripping means that has reached the electrode mounting position.

An embodiment of the present invention will be explained with reference to FIGS. 1 and 2.

In FIGS. 1 and 2, an electrode 11 having a plurality of mounting positions is rotatably installed inside the processing chamber 10. As shown in FIG. A light passage hole 12a is formed in the electrode 11 at each mounting position. Light passing windows 13a and 13b are provided on the bottom wall and top wall of the processing chamber 10, coaxially with the light passing hole 12a. A light emitting element 14 and a light receiving element 15 are provided on the outside of the light passing windows 13a and 13b coaxially with the light passing hole 12a. In the preliminary chamber 16 provided in the processing chamber 10,
A wafer supply device (hereinafter referred to as the supply device) (not shown) and a wafer recovery position (hereinafter referred to as the recovery device) (not shown) are provided, and the wafers 20 supplied by the supply device are transported from the preliminary chamber 16 to the electrodes. An arm 17 for transporting the wafer 20 to the mounting position of the electrode 11 and transporting the wafer 20 from the mounting position of the electrode 11 to a recovery device in the preparatory chamber 16 is, for example, provided internally so as to be partially rotatable. The arm 17 is provided with gripping means 18. The gripping device 18 includes gripping means 1
When the electrode 8 reaches the placement position of the electrode 11, a light passage hole 12b is formed so as to face the light passage hole 12a.

First, the electrode 11 is rotated so that the light passage hole 12a, the light emitting element 14, and the light receiving element 15 are coaxial. In this case, the gripping means 18 are in a position corresponding to the feeding device. In this state, light is emitted from the light emitting element 14. If the wafer 20 is not placed at the position where the electrode 11 is placed, this light
The light passes through the light passage hole 12a and is received by the light receiving element 15, and as a result, it is determined that there is no light. Therefore, the wafer 20 supplied by the supply device is grasped by the grasping means 18, and in this state, the arm 17 is moved to the processing chamber 1.
By partially rotating toward the 0 side, the gripping means 18 reaches the wafer placement position of the electrode 11. Thereafter, the wafer 20 gripped by the gripping means 18 is transferred to the gripping means 1
8 and placed at the placement position of the electrode 11.
Thereafter, the electrode 11 is further rotated so that the light passing hole 12b, the light emitting element 14, the light receiving element 15, and the adjacent light passing hole 12a are coaxial with the gripping means 18 left as is. When the wafer 20 is placed at this placement position of the electrode 11, the light emitting element 1
The light emitted from wafer 20
The light is blocked by the light receiving element 15 and is not received by the light receiving element 15. As a result, it is determined that there is. Further, when the wafer 20 is not placed at this placement position of the electrode 11, the light emitted from the light emitting element 14 passes through the light passage holes 12a and 12b and is received by the light receiving element 15, and as a result, It is judged as nothing. If it is determined that the wafer 20 is present and the wafer 20 is unprocessed, the gripping means 18 is left as it is, and the light passing hole 12, the light emitting element 14, the light receiving element 15 and the adjacent light passing hole 1
The electrode 11 is further rotated so that it is coaxial with the electrode 2a. On the other hand, if the wafer 20 has been processed, the wafer 20 is gripped by the gripping means 18, and in this state, the arm 17 is partially rotated to a position where the gripping means 18 corresponds to the collecting device. When the gripping means 18 reaches a position corresponding to the collecting device, the wafer 20 gripped by the gripping means 18 is released and collected by the collecting device. Thereafter, the gripping means 18 moves the arm 1
The wafer 2 reaches the position corresponding to the supply device by the partial rotation of step 7, and the wafer 2 that has been supplied by the supply device
Grab 0. This wafer 20 is then placed at the placement position of the electrode 11 in the same manner as described above. In addition, if it is determined that there is no gripping means 18
By partially rotating the arm 17, the wafer 20 is moved to the position corresponding to the supply device, and the wafer 20 supplied by the supply device is transferred to the electrode 1 in the same manner as described above.
Place it on the 1st placement position.

In the wafer transport device of this embodiment, the presence or absence of a wafer at the electrode mounting position can be appropriately determined without once shifting the gripping means from the electrode mounting position, reducing the overall wafer transport time. It is possible to improve throughput.

In this embodiment, a case has been described in which the gripping means is provided on an arm that partially rotates, but the gripping means may also be provided on an arm that moves straight.

As explained above, the present invention can appropriately determine the presence or absence of a wafer at the electrode mounting position without once shifting the gripping device from the electrode mounting position, thereby reducing the overall wafer transport time. This has the effect of shortening the time and improving throughput.

[Brief explanation of the drawing]

1 and 2 illustrate an embodiment of the present invention, and FIG. 1 is a partial longitudinal sectional view of a semiconductor manufacturing apparatus to which a wafer transfer apparatus according to the present invention is applied;
FIG. 2 is a partial plan view taken along the line AA in FIG. 1. 10... Processing chamber, 11... Electrode, 12a, 12
b... Light passing hole, 14... Light emitting element, 15... Light receiving element, 16... Preliminary chamber, 17... Arm, 18
...Means of grasping.

Claims (1)

[Scope of utility model registration request] A wafer gripping means for gripping and transporting a wafer between a wafer mounting position of an electrode rotatably installed in the processing chamber and a preliminary chamber includes a light emitting element and a wafer gripping means provided on the optical axis of light from the light emitting element. a light passing window provided in the processing chamber corresponding to each of the light receiving elements; and a light passing hole formed in the wafer mounting position of the electrode so as to correspond to the light passing window; A wafer transfer device characterized by having holes.