JP2000252335A - Production system of semiconductor - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent a chipping wafer from causing a process abnormality or a processing trouble by providing a wafer chipping detection means at a wafer carry-in/carry-out section adjacent to a processing chamber. SOLUTION: A cassette 1 is set at the carry-in/carry-out section 8 of a semiconductor production system 9 and a robot is provided at the carry-in/carry-out section 8. Wafers 2 in the cassette 1 are taken out sheet by sheet and carried in the direction of arrow A before being mounted on an aligner 3. A CCD camera 4 disposed above the aligner 3 picks up the image of the wafer 2. The image data is processed by an image processor 10 in order to discriminate whether a wafer 2 is chipping or not. When chipping is detected by the discrimination, the wafer 2 is removed as a defective wafer by means of the robot and next wafer 2 is taken out from the cassette 1 and mounted similarly on the aligner 3.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a semiconductor manufacturing apparatus. More specifically, the present invention relates to chipping detection of a wafer.

[0002]

2. Description of the Related Art In a semiconductor manufacturing process, a semiconductor wafer is subjected to various processes such as impurity diffusion, sputtering, CVD, and etching for forming a thin film. Wafers are carried in cassettes for each lot (usually 25 wafers). The carried cassette is set in a carry-in / carry-out section of each processing apparatus such as CVD or etching. In the loading / unloading section, a transfer means such as a robot takes out the wafers one by one from the cassette, loads them into the processing chamber, and returns the processed wafers to the cassette. Such a semiconductor manufacturing apparatus is installed in a clean room and operated under sufficient control in an environment in which dust and the like are eliminated, thereby improving the reliability of wafer processing.

[0003]

However, the wafer may have defects such as chipping. This chipping is a defect such as a chip generated on the peripheral portion of the wafer 2 as shown in FIG. If the wafer having such a chipping 7 is contained in the cassette, the following problem occurs.

(1) When a wafer is processed in a high-temperature or vacuum atmosphere in each processing apparatus or when the wafer is transported, the wafer breaks from a chipping portion.

(2) Fragments of broken wafers become dust and cause contamination and damage of the apparatus, and also have an adverse effect on subsequent wafers, such as cracks, scratches, and adhesion of debris, resulting in process abnormalities. .

(3) The apparatus must be stopped for a long time in order to clean up the broken wafer, which causes downtime of the apparatus and lowers the operation rate.

(4) If the chipping wafer is processed as it is and transported to a subsequent step, the above-mentioned failures (1) to (3) may occur in the subsequent step.

The present invention has been made in consideration of the above-mentioned problems of the prior art, and is intended to prevent a process abnormality or an obstacle to processing due to a chipping wafer, to manufacture a highly reliable semiconductor product and to improve a yield. The purpose is to provide a manufacturing apparatus.

[0009]

In order to achieve the above object, according to the present invention, there is provided a semiconductor manufacturing apparatus wherein a wafer chipping detecting means is provided at a wafer loading / unloading section adjacent to a processing chamber. provide.

[0010] According to this configuration, since chipping of the wafer is detected before the wafer is carried into the processing chamber, it is possible to take measures such as eliminating the wafer for which chipping has been detected, thereby preventing a process failure. it can. Also,
By detecting chipping of the wafer carried out of the processing chamber, it is possible to cope with the cause of chipping in the processing chamber and to prevent a process failure due to the chipping wafer in the next step.

In a preferred embodiment, the chipping detecting means comprises an image processing device using a CCD camera.

With this configuration, the wafer is imaged by the CCD camera, and chipping is detected by image processing of the imaged data.

In another preferred embodiment, the chipping detecting means comprises an optical sensor.

According to this configuration, the chipping of the wafer is detected by the optical sensor such as the transmission type or the reflection type.

In a further preferred configuration example, when chipping is detected during unloading of the wafer, the wafer processing in the processing chamber is controlled to be stopped.

According to this configuration, when chipping is detected in the wafer carried out of the processing chamber after the processing is completed, there is caused a factor of causing chipping in the processing chamber or an adverse effect such as contamination due to chipping. Therefore, it is possible to stop the processing in the processing room and take measures.

[0017]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is a configuration diagram of a semiconductor manufacturing apparatus according to an embodiment of the present invention. Twenty-five wafers 2 for one lot to be processed are horizontally laid one above the other with a vertical interval and are slidably accommodated in the cassette 1. The cassette 1 is set in the loading / unloading section 8 of the semiconductor manufacturing apparatus 9. The loading / unloading unit 8 is provided with a robot (not shown), and takes out the wafers 2 in the cassette 1 one by one, transfers them in the direction of arrow A, and mounts them on the positioning device 3. The wafer 2 is set at a predetermined position on the alignment device 3 with reference to the orientation flat 2a (see FIG. 2) of the wafer 2.

In the present embodiment, a CCD camera 4 is installed at a position above the alignment device 3 to image the wafer 2. The image data is subjected to image processing by the image processing device 10 to determine whether or not the wafer 2 has chipping. If chipping is detected, this wafer is removed as a defective wafer by a robot, and the next wafer is taken out of the cassette 1 and mounted on the alignment device 3 in the same manner.

The wafer 2 determined to have no chipping by the image processing is carried by the robot as shown by the arrow B and is carried into the processing chamber 6. The wafer 2 that has been subjected to the predetermined processing in the processing chamber 6 is transferred to the processing chamber 6 by a robot.
Is carried out as shown by arrow C, and is mounted on the positioning device 3 again. Here, the image is picked up again by the CCD camera 4 and the presence or absence of chipping is determined. When chipping is detected in the wafer 2 by the chipping detection at the time of unloading, the processing in the processing chamber 6 is temporarily stopped because the chipping occurred during wafer processing in the processing chamber 6. Investigate the cause and deal with it, and remove the contamination due to chipping debris.

The wafer 2 mounted on the positioning device 3 at the time of unloading and for which no chipping has been detected is transported by the robot as shown by the arrow D and returned into the cassette 1 (or stored in a new cassette).

The wafer processing in the processing chamber 6 is processing in various semiconductor manufacturing processes such as CVD processing, dry etching processing, sputtering processing, impurity diffusion processing, ion implantation processing, and the processing chamber 6 is configured as a vacuum chamber. You. The processing chamber 6 may include a pre-vacuum chamber for maintaining the degree of vacuum in the processing chamber 6 when a wafer is taken in and out. In this case, the positioning device is provided in or outside the pre-vacuum chamber.

As a means for detecting chipping of the wafer, a reflection type sensor or a transmission type sensor using a combination of a laser beam from a light emitting element and a light receiving element for photoelectric conversion is used instead of the configuration of the CCD camera 4 and the image processing apparatus 10. An optical sensor may be used.

[0023]

As described above, in the present invention, since chipping of a wafer is detected before the wafer is carried into the processing chamber, it is possible to take measures such as removing the wafer for which chipping has been detected. A process failure in the processing chamber can be prevented. Further, by detecting chipping of the wafer carried out of the processing chamber, it is possible to cope with the cause of chipping in the processing chamber and to prevent a process failure due to the chipping wafer in the next step. As a result, the reliability of wafer processing in each process can be increased, downtime can be reduced, productivity can be improved, and the yield can be improved, and a highly reliable semiconductor device can be manufactured.

[Brief description of the drawings]

FIG. 1 is a configuration diagram of a semiconductor manufacturing apparatus according to an embodiment of the present invention.

FIG. 2 is an explanatory view of a chipping wafer.

[Explanation of symbols]

1: cassette, 2: wafer, 3: alignment device,
4: CCD camera, 6: processing room, 7: chipping, 8:
Loading / unloading unit, 9: semiconductor manufacturing device, 10: image processing device.

Claims (4)

[Claims] 1. A semiconductor manufacturing apparatus, wherein a wafer chipping detecting means is provided at a wafer loading / unloading section adjacent to a processing chamber. 2. The semiconductor manufacturing apparatus according to claim 1, wherein said chipping detecting means comprises an image processing device using a CCD camera. 3. The semiconductor manufacturing apparatus according to claim 1, wherein said chipping detecting means comprises an optical sensor. 4. The semiconductor manufacturing apparatus according to claim 1, wherein when chipping is detected at the time of unloading the wafer, the semiconductor processing apparatus is controlled to stop wafer processing in the processing chamber.