JPH1140647A - Detecting mechanism for semiconductor substrate - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make it possible to discriminate occasions when there are no substrates from those when a substrate is inclined on a mount table, by detecting the posture of the mounted substrate with one photodetector discriminating the difference of angles of reflection of the upper surface of the substrate, and detecting a light reflected from the hole having a bottom of the mount table with the other photodetector when there are no substrates. SOLUTION: A hole 15 having a bottom is formed in the surface of a mount table 12 liked to a robot arm 4. When a substrate 1 is positioned and put on a regular position on the mount table 12, a reflected light by the substrate 1 from a light emitting element 17 is detected by a first photodetector 18a. When there are no substrates 1, a light is reflected by the bottom surface of the hole 15 of the mount table 12, and detected by a second photodetector 18b. Consequently, it becomes possible to make processing at the time of malfunctioning more appropriate, and to increase the rate of operation of processing facilities. And it becomes possible to detect reliability lowering of the conveyance of the processing facilities earlier, and to prevent the generation of troubles.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a transfer apparatus for processing a semiconductor substrate or a flat glass substrate (hereinafter abbreviated as "substrate") in a process such as plasma CVD or plasma etching. The present invention relates to a detection mechanism for checking and detecting the posture or the presence or absence of a substrate.

[0002]

2. Description of the Related Art FIG. 2 is a plan sectional view (a) showing a conventional substrate detecting mechanism and a side sectional view (b) as viewed from the direction of arrow F. In FIG. 2A, for example, the robot arm 3,
4 and a transport mechanism including the mounting table 2, each time the substrate 1 is transferred from the processing chamber A to the processing chamber B,
Processing equipment for removing troubles associated with the transfer of the substrate 1 by detecting the posture of the substrate 1 due to the light reflection action or the presence or absence of the substrate 1 by using an optical sensor having a light receiving element 8 Has confirmed its reliability. The presence or absence of the substrate 1 is determined by providing a hole 5 on the robot arm 4
The signal detection accuracy is improved by increasing the / N ratio.

[0003]

In FIG. 2 (a),
When the substrate 1 is transferred from the processing chamber A side to the processing chamber B side, one end of the substrate 1 rides on the positioning pins 6, and as shown in FIG.
As shown in (1), when the surface of the substrate 1 is inclined like 1 ', the light from the light emitting element 7 is detected out of the detection range of the light receiving element 8 due to a change in the reflection angle with respect to the substrate 1. Therefore, when it is determined that the substrate 1 does not exist, that is, the substrate 1 is not mounted, the processing equipment may be stopped. That is, the substrate 1
There is a problem that it is impossible to discriminate between the case where the posture is not regular and the case where the substrate 1 is not provided. Normally, in the case where the substrate 1 is only tilted to the above degree, the processing equipment is stopped in the above-described conventional technology, although the transfer can be performed as it is, and the operating rate is greatly reduced. Invite. An object of the present invention is to eliminate the problem of the prior art, that is, the case where the substrate 1 is not provided and the case where the substrate 1 is tilted on the mounting table 2, thereby eliminating a situation in which processing equipment is stopped. Another object of the present invention is to provide a substrate detection mechanism suitable for improving the operation rate.

[0004]

The above object is achieved by an optical sensor (not shown) having two light receiving elements at different positions with respect to one light emitting element, and one of the light receiving elements is mounted on a substrate. This is achieved by a configuration in which the difference in the reflection angle on the upper surface of the substrate is determined and detected for the posture, and the other light receiving element detects light reception by reflection from the bottomed hole of the mounting table when the substrate is not provided. That is, in detecting the posture of the substrate placed at the regular position on the mounting table, the light reflected by the semiconductor substrate from the light emitting element is detected by the first light receiving element, but the light is deviated from a predetermined position on the mounting table. The inclination of the posture of the substrate that is standing still cannot be detected. In the case where no substrate is provided, the light reflected from the bottomed hole provided in the mounting table is detected and received by the second light receiving element.
INDUSTRIAL APPLICABILITY The present invention is effective for a detection mechanism for confirming and detecting not only the mounted semiconductor substrate but also the posture or the presence or absence of various planar glass substrates mounted on a mounting table.

[0005]

Embodiments of the present invention will be described with reference to the drawings. FIG. 1 is a sectional view of a main part showing a detection mechanism of the present invention. In FIG. 1, 17 is a light emitting element, 18
Reference numerals a and 18b denote first and second light receiving elements. A bottomed hole 15 is provided on the surface of the mounting table 12 engaged with the robot arm 4. When the substrate 1 is positioned and mounted at a regular position on the mounting table 12, the light reflected by the substrate 1 from the light projecting element 17 is detected by the first light receiving element 18a. Is reflected from the bottom surface of the bottomed hole 15 of the mounting table 12 and detected by the second light receiving element 18b.

When one end of the substrate 1 is not positioned at a regular position but rides on the positioning pins 16 and the surface of the substrate 1 is inclined as 1 ', light from the light emitting element 17 Of the first light receiving element 18a cannot be detected due to a change in the reflection angle with respect to the first light receiving element 18a. However, if the inclination of the substrate 1 is such that the substrate 1 has climbed onto the positioning pins 16 as shown in FIG. 1, it can be transported as it is, without causing any particular trouble or trouble in the process processing, and stopping the processing equipment. There is no need to do this.
However, if the second light receiving element 18b detects the reflected light from the bottom surface of the bottomed hole 15, it is determined that the substrate 1 is not mounted. Therefore, a measure such as stopping the apparatus is necessary depending on the situation.

[0007]

According to the substrate detecting mechanism of the present invention, the improvement of the simple structure allows the conventional case where the substrate is not present on the mounting table and the case where the substrate is tilted from the normal posture. Can be distinguished. As a result, the treatment at the time of the abnormality becomes more accurate, the operation rate of the processing equipment can be improved, the decrease in the reliability of the transportation of the processing equipment can be detected early, and the occurrence of an accident can be prevented.

[Brief description of the drawings]

FIG. 1 is a sectional view of a main part showing a detection mechanism of the present invention.

FIG. 2A is a plan sectional view showing a conventional substrate detecting mechanism, and FIG. 2B is a side sectional view taken along arrow F.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 ... Substrate 2 ... Mounting table 3, 4 ... Robot arm 5 ... Hole 6 ... Positioning pin 7 ... Light emitting element 8 ... Light receiving element 12 ... Mounting table 15 ... Bottomed hole 16 ... Positioning pin 17 ... Light emitting element 18a ... 1st light receiving element 18b ... second light receiving element

Claims (1)

[Claims] 1. A detecting mechanism for detecting and confirming the posture of a semiconductor substrate on a transfer device or the presence or absence of a substrate in a semiconductor processing step, wherein: a mounting table for positioning and mounting the semiconductor substrate at a predetermined position; A bottomed hole having a reflection plane on the mounting table below the positioned semiconductor substrate; a light emitting element for projecting light on the upper surface of the semiconductor substrate mounted on the predetermined position; and an upper surface of the semiconductor substrate mounted on the predetermined position A first light receiving element provided so as to receive the reflected light from the light emitting element due to the above, and not to receive the reflected light from the upper surface of the semiconductor substrate, which is deviated from the predetermined position, and A second light-receiving element for receiving light reflected from the bottomed hole when not performed.