JPH10270522A - Substrate transfer machine - Google Patents

Abstract

(57) [Summary] In a substrate transfer machine, a substrate is transported in order to stably load a substrate, transport the substrate at high speed, and respond to a demand for a large-diameter substrate to be processed. Increase the size of the plate. A substrate detection sensor is provided to face a substrate transport plate for receiving a substrate, a portion of the substrate transport plate that coincides with a detection medium projection axis of the substrate detection sensor is deleted, and a substrate detection sensor is provided. The emitted detection medium passes through the substrate transport plate, and the presence of the substrate blocks transmission of the detection medium, thereby detecting the substrate.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate transfer machine for transferring a substrate such as a wafer in a semiconductor manufacturing process.

[0002]

2. Description of the Related Art A substrate to be processed is transferred inside a semiconductor manufacturing apparatus by a substrate transfer machine. The substrate transfer machine is provided with a plurality of substrate transfer plates so that a plurality of substrates to be processed can be transferred at a time, and each of the substrate transfer plates is provided for detecting the presence or absence of the substrate to be processed on the substrate transfer plate. Is provided with a substrate detection sensor.

First, referring to FIG. 5, an outline of a semiconductor manufacturing apparatus including a substrate transfer machine will be described.

[0004] A reaction furnace 2 is provided at an upper rear position in the housing 1, and a reaction tube 3 is provided inside the reaction furnace 2. A boat elevator 4 is provided below the reaction furnace 2, and the boat elevator 4 loads a boat 6 loaded with a wafer 5 as a substrate to be processed into the reaction tube 3.
Withdraw.

The wafer 5 is transferred between the semiconductor manufacturing apparatus and the outside while being loaded in the wafer cassette 7. The wafer cassette 7 is relayed by a wafer cassette transfer unit (not shown) located in the front part of the housing 1, and is provided to face the wafer cassette transfer unit (not shown) by a cassette transporter 8. Buffer cassette shelves 9 and cassette shelves 10. The reactor 2
A first air clean unit 11 is provided between the first air clean unit 11 and the cassette transporter 8.
A second air clean unit 12 is provided below the unit. A wafer transfer device 13 is provided between the cassette shelf 10 and the boat elevator 4. The wafer transfer machine 13 transfers the wafers 5 between the wafer cassette 7 stored in the cassette shelf 10 and the boat 6 in a lowered state.

As described above, the boat elevator 4 loads the boat 6 into the reaction tube 3 and pulls out the boat 6 from the reaction tube 3 when the film formation on the wafer 5 is completed.

The processed wafers 5 are transferred from the boat 6 to the wafer cassette 7 of the cassette shelf 10 by performing a procedure reverse to the transfer to the boat 6. 7 is carried out of the semiconductor manufacturing apparatus.

Next, the wafer transfer device 13 will be described with reference to FIGS.

The wafer transfer machine 13 has a vertically movable and rotatable advance / retreat mechanism 14, and the advance / retreat mechanism 14 is provided with a chucking head 15 which can be moved forward and backward in the horizontal direction. The chucking head 15 includes a plate holding unit 16.
A wafer transfer plate 17 is vertically mounted on the plate holding portion 16 in a required direction (five stages in the figure).

The wafer transfer plate 17 has a tapered shape in which the base end is wide and the front end is narrow when attached to the plate holding portion 16. Further, a concave portion 18 into which the wafer 5 is fitted is formed on the upper surface side of the wafer transfer plate 17. Step portions 20 are protruded at four places. The step portion 20 is lowered from the upper surface of the wafer transfer plate 17, and the wafer 5 to be transferred is fitted into the concave portion 18, is supported at four peripheral edges by the step portion 20, and Is out of contact.

One side of the plate holding portion 16 has
A pair of arms 21 are fixed to the wafer transfer plate 17 at required steps (six steps in the figure) vertically above and below the wafer transfer plate 17. The arm 21 extends in a direction parallel to a tangent to the step 20 on the arm 21 side of the wafer 5 to be received,
The tip of the arm 21 does not interfere with the wafer cassette 7.

A rod-shaped sensor support 22 is provided at the tip of the arm 21 so as to form a right angle with the arm 21 in parallel with the wafer transfer plate 17. A light receiving device 2 of a wafer detection sensor is provided at the tip of the sensor support 22.
3, a light emitter 25 of a wafer detection sensor is installed at the tip of another sensor support 24 forming a pair, and an optical axis 26 of the light receiver 23 and an optical axis 27 of the light emitter 25 coincide with each other. It is positioned.

The sensor supports 22, 24 have their axes centered in the direction of the center of the concave portion 18, and their tips are located near the side edges of the transport plate 17,
The optical axis 26 of the light receiver 23 and the optical axis 27 of the light projector 25
Is located outside the recess 18 and the wafer 5 to be received
It is arranged so that it may be located inside the outline of.

Next, a wafer transfer operation, for example, a case where the wafer 5 is removed from the wafer cassette 7 will be described.

The chucking head 15 is retracted,
Rotating the advance / retreat mechanism 14 so that the wafer transfer plate 17 does not project from the advance / retreat mechanism 14,
The chucking head 15 is moved to the wafer cassette 7
To the open surface 28. The chucking head 1
5, the wafer transfer plate 17 is inserted into the wafer cassette 7, the transfer mechanism elevator (not shown) slightly raises the advance / retreat mechanism 14, and moves the wafer 5 to the stepped portion of the wafer transfer plate 17. 20.

The presence or absence of the wafer 5 on the wafer transfer plate 17 is determined by whether or not the detection light from the light projector 25 is blocked by the wafer 5.
That is, if the detection light is not detected by the light receiver 23, the presence of the wafer 5 is determined, and if the detection light is detected by the light receiver 23, the absence of the wafer 5 is determined. When there is no wafer 5, the transfer operation is stopped.

[0017]

In the above-mentioned conventional wafer transfer machine, the wafer is mounted in order to stably load the wafer and transfer it at a high speed, or to meet a demand for a large-diameter wafer. When the size of the transfer plate 17 is increased, the length of the arm 21 is increased so that the detection light is not blocked by the wafer transfer plate 17, or the arm 21 is connected to the wafer transfer plate 17. The arm 21 interferes with the wafer cassette 7 when the wafer transfer plate 17 is inserted into the wafer cassette 7 to remove a wafer from the wafer cassette 7. There was a problem.

The present invention has been made in view of the above circumstances, and when the wafer transfer plate is inserted into the wafer cassette, the arm transfer does not interfere with the wafer cassette and the substrate transfer plate can be enlarged in size. Is to offer a machine.

[0019]

According to the present invention, a substrate detection sensor is provided opposite to a substrate transport plate for receiving a substrate, and a portion of the substrate transport plate which coincides with a detection medium projection axis of the substrate detection sensor is provided. Regarding the removed substrate transfer machine,
Further, the present invention relates to a substrate transfer machine in which the substrate detection sensor is provided in a rod-shaped sensor support, and an arm supporting the sensor support does not protrude beyond the maximum width of the substrate transfer plate.
Furthermore, the present invention relates to a substrate transfer machine in which the detection medium is light, the detection medium emitted from the substrate detection sensor transmits through the substrate transport plate, and the detection medium is blocked by the presence of the substrate, thereby detecting the substrate. Further, since the arm does not protrude beyond the maximum width of the substrate transport plate, interference between the arm and other components can be avoided, and the substrate transport plate can be made larger.

[0020]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to FIGS. In FIGS. 1 to 4, FIG.
8 are denoted by the same reference numerals, and description thereof is omitted.

The wafer transfer device 13 has a chucking head 15, and a plate carrier 16 of the chucking head 15 is provided with a required stage, in this embodiment, five stages of wafer transfer plates 36.

The wafer transfer plate 36 has a tapered shape in which the base end is wide and the front end is narrow when attached to the plate holding portion 16, and the base end is in contact with the wafer cassette 7. Be as wide as possible.
The wafer 5 is placed on the upper surface of the wafer transfer plate 36.
Is formed, and a boundary line 38 of the recess 37 is formed.
At the width end position, step portions 39 are projected at two locations on the base end side and two places on the distal end side in total. The step portion 39 is lowered below the upper surface of the wafer transfer plate 36, and the wafer 5 to be transferred is fitted into the concave portion 37, and is supported at four peripheral edges by the step portion 39.
Is in non-contact.

Further, a square hole 40 with rounded corners is formed in the wafer transfer plate 36 in the vicinity of one of the step portions 39 on the base end side boundary line 38 of the concave portion 37. Have been. The position of the hole 40 is made coincident with the optical axis of the detection light, that is, the projection axis of the detection medium, as described later.

On the side surface of the plate holding portion 16 on the side where the holes 40 are formed, a pair of arms 41 are provided for a single wafer transfer plate 36 at required steps vertically with the wafer transfer plate 36 interposed therebetween. In this embodiment, six stages are fixed. The arm 41 extends in a direction parallel to a tangent line of the received wafer 5 at the step portion 39 on the arm 41 side, and the tip of the arm 41 does not interfere with the wafer cassette 7. I have.

At the tip of the arm 41, a rod-shaped sensor support 42 is provided in parallel with the wafer transfer plate 36 so as to form a right angle with the arm 41. A light receiving device 4 of a wafer detection sensor is provided at the tip of the sensor support 42.
3, a light emitter 45 of the wafer detection sensor is installed at the tip of the other sensor support 44 forming a pair, and the optical axis 46 of the light receiver 43 matches the optical axis 47 of the light emitter 45. It is positioned.

The sensor supports 42 and 44 have the axes of the sensor supports 42 and 44 pointing toward the center of the recess 37, and the optical axis 46 of the light receiver and the optical axis 47 of the light projector correspond to the holes 40. It is disposed so as to be located on the center direction side of the concave portion 37 with respect to the boundary line 38 and the tip position of the arm 41 is located inside the maximum width end of the wafer transfer plate 36.

Therefore, since the maximum width of the wafer transfer plate 36 can be determined without considering the interference between the arm 41 and the wafer cassette 7, the allowable limit in the relationship between the wafer transfer plate 36 and the wafer cassette 7 can be determined. Can be up to. Thus, the distance between the support points by the base-side step 39 is widened, and the support of the wafer is stabilized.

Next, a wafer transfer operation, for example, a case where the wafer 5 is removed from the wafer cassette 7 will be described.

The chucking head 15 is retracted,
Rotating the advance / retreat mechanism 14 so that the wafer transfer plate 36 does not project from the advance / retreat mechanism 14,
The chucking head 15 is moved to the wafer cassette 7
To the open surface 28. The chucking head 1
5, the wafer transport plate 36 is inserted into the wafer cassette 7, the advance / retreat mechanism 14 is slightly raised by a transfer machine elevator (not shown), and the wafer 5 is moved to the stepped portion of the wafer transport plate 36. Place on 39. As described above, the base-side step 3
9, the distance between the support points is widened.
Support is stable.

The presence or absence of the wafer 5 on the wafer transfer plate 36 is determined by whether or not the detection light from the light projector 45 is blocked by the wafer 5.
That is, when the wafer 5 is placed on the wafer transfer plate 36, the detection light from the light emitter 45 is blocked by the wafer 5 and does not reach the light receiver 43, so that the presence of the wafer 5 exists. When the determination is made and the wafer 5 is not placed on the wafer transfer plate 36, the detection light from the light emitting device 45 passes through the hole 40 and reaches the light receiving device 43. A determination of 5 is made. When there is no wafer 5, the transfer operation is stopped.

Although the holes 40 are formed in the wafer transfer plate 36 in the above embodiment, the holes 40 may be notches 48 as shown in FIG. Further, four step portions 39 are provided in the concave portion 37 of the wafer transfer plate 36, but may be five or more, and the width of the front end portion of the wafer transfer plate 36 may be in contact with the wafer cassette 7. It may be longer as long as it does not. Furthermore, although light was used as the detection medium of the wafer detection sensor, ultrasonic waves may be used,
Further, the detection type may be a reflection type instead of a transmission type. Further, the detection target substrate is not limited to a wafer, but can be applied to various substrates such as a glass substrate.

[0032]

As described above, according to the present invention, the detection position for detecting the presence / absence of the substrate to be processed is located inside the outline of the substrate transfer plate, and the arm projects beyond the maximum width of the substrate transfer plate. Since the interference between the arm and other parts can be avoided by not doing so, the outer shape of the board transfer plate can be determined without being affected by the presence of the board detection sensor, so that the size of the board transfer plate can be increased. I can do it. Accordingly, the support points of the substrate to be processed by the substrate transfer plate are widened, and the substrate to be processed can be stably mounted on the substrate transfer plate, so that the substrate to be processed can be transferred at a high speed. Even if the diameter of the processing substrate is increased, various excellent effects are exhibited, such as the substrate to be processed can be transported with good stability.

[Brief description of the drawings]

FIG. 1 is a perspective view showing an embodiment of the present invention.

FIG. 2 is a plan view showing a state in which a wafer transfer plate of the wafer transfer machine according to the embodiment is inserted into a wafer cassette.

FIG. 3 is a sectional view taken along line AA of FIG. 2;

FIG. 4 is an enlarged plan view of a cutout portion of a wafer transfer plate according to another embodiment of the present invention.

FIG. 5 is a perspective view schematically showing a semiconductor manufacturing apparatus.

FIG. 6 is a perspective view showing a conventional example.

FIG. 7 is a plan view showing a state in which a wafer transfer plate of a conventional wafer transfer machine is inserted into a wafer cassette.

FIG. 8 is a sectional view taken along the line BB of FIG. 7;

[Explanation of symbols]

 36 Wafer transfer plate 39 Step section 40 Hole 41 Arm 43 Light receiver 45 Light emitter 48 Notch

Claims (3)

[Claims] 1. A substrate, wherein a substrate detection sensor is provided to face a substrate transport plate for receiving a substrate, and a portion of the substrate transport plate that coincides with a detection medium projection axis of the substrate detection sensor is deleted. Transfer machine. 2. The apparatus according to claim 1, wherein said substrate detection sensor is provided inside a rod-shaped sensor support, and an arm supporting said sensor support does not protrude beyond a maximum width of the substrate transfer plate.
Substrate transfer machine. 3. The substrate transfer device according to claim 1, wherein the detection medium is light.