JPH10242249A - Method and apparatus for detecting substrate in cassette - Google Patents

Abstract

PROBLEM TO BE SOLVED: To surely detect a substrate in a cassette with simplifying the structure, utilizing a substrate carrying robot moving function. SOLUTION: A robot arm 4 for taking out a substrate W stored in a cassette C and carrying it to a predetermined treating zone is controlled to hold and carry a substrate detecting sensor S mounted on a sensor mount 9 to a position facing the cassette C, move the sensor S in the laminating direction of the substrates W laminated in the cassette, and return the sensor S to the mount 9 after the end of the detecting operation.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for detecting the presence or absence of a substrate such as a semiconductor wafer stacked and stored in a cassette in multiple stages, a storage posture, and the like, and a detection apparatus for executing the method.

[0002]

2. Description of the Related Art In a substrate processing apparatus in which substrates stacked and stored in a cassette in a multi-stage manner are taken out one by one by a robot arm and processed, first, when a cassette is loaded in a predetermined position, the substrate storage in the cassette is first performed. It is necessary to know the condition. For this purpose, a sensor is scanned at a plurality of positions in the circumferential direction of the substrate in the substrate stacking direction, that is, in the vertical direction, to detect the presence or absence of the substrate. This ensures that the boards are correctly accommodated in parallel, or
It is possible to determine whether or not there is a stage in which no substrate is stored.

Conventionally, the following forms have been known as such detection means. As a general form, there is a type in which a cassette mounting table for positioning and mounting a cassette and a substrate detection sensor are relatively moved up and down to detect a substrate in the cassette.

[0004] As another form, a substrate transfer robot is provided with two arms which can move forward and backward, a substrate is transferred by one arm, a substrate detection sensor is attached to the other arm, and the other arm is connected to the other arm. By moving the sensor up and down close to the cassette, the sensor scans in the substrate stacking direction,
Some devices detect a substrate in a cassette.

[0005]

However, the above conventional method has the following problems. In the former case, an elevating drive mechanism for elevating the cassette mounting table or the substrate detection sensor is required, and the device configuration is complicated. Further, if the size of the substrate changes, the distance between the edge of the substrate and the sensor changes. In each case, it is necessary to adjust the sensitivity of the sensor and the like, and there is a difficulty in workability.

In the latter embodiment, since the sensor can be moved by using the movement function of the substrate transfer robot, a dedicated drive mechanism for moving the sensor is not required, and the size of the substrate changes. This also has the advantage that the distance between the edge of the substrate and the sensor can be made constant only by changing the position of the arm, so that the sensitivity adjustment of the sensor becomes unnecessary. However, in this mode, another arm for the sensor must be provided in addition to the original arm for transferring the substrate, and the arm structure becomes complicated, and the sensor arm does not hinder the substrate transfer operation. Need to be considered.

The present invention has been made in view of such a situation, and has a simple structure while utilizing the latter advantage that the sensor can be moved by using the movement function of the substrate transfer robot. It is an object of the present invention to provide a method and an apparatus for detecting a substrate in a cassette which can be realized.

[0008]

According to the present invention, the following means and configurations are provided to achieve the above object. That is, in the method for detecting a substrate in a cassette according to the first aspect, a substrate detection sensor stored and held at a predetermined position is held by a substrate transfer robot arm, and the robot arm is moved to accommodate the substrate detection sensor in the cassette. The detected substrate is detected by the sensor.

According to a second aspect of the present invention, there is provided a device for detecting a substrate in a cassette, comprising: a cassette mounting table for positioning and mounting the cassette; A sensor for detecting a substrate that is attached to and detached from the tip of the robot arm;
A sensor mounting table for positioning and mounting the substrate detection sensor detached from the robot arm, and a substrate detection sensor mounted on the sensor mounting table held by the robot arm and carried out, and the substrate detection sensor is cassette. The robot arm is moved so as to move the robot arm in the stacking direction of the substrates stacked in the cassette and return the substrate detection sensor to the sensor mounting table again after the detection operation is completed. Control means.

According to a third aspect of the present invention, there is provided the substrate detecting device in the cassette according to the second aspect, wherein the substrate detecting sensor detects the substrate based on the reflection of the laser light projected toward the edge of the substrate. It utilizes a reflective laser sensor for detection.

According to a fourth aspect of the present invention, there is provided the substrate detecting device in the cassette according to the third aspect of the present invention, wherein two reflection type laser sensors are juxtaposed as a substrate detecting sensor, and the same substrate is detected by both sensors. It is configured to detect.

[0012]

The operation of the present invention is as follows. According to the first and second aspects of the present invention, prior to the substrate processing, the storage state of the substrates in the cassette is detected, and the robot arm takes out the substrate detection sensor stored on the sensor mounting table to remove the cassette. By moving to the front and detecting the substrate edge while scanning in the substrate stacking direction, the presence or absence of the substrate and the storage posture are determined, and the information is stored. When the detection process is completed, the robot arm is moved and is returned to the held substrate detection sensor / sensor mounting table, and thereafter, the robot arm is engaged in the original substrate transfer.

Here, if a reflection type laser sensor is used as the substrate detecting sensor, the edge of the thin substrate can be detected with high accuracy by using the narrowed laser light (the invention according to claim 3). Further, at this time, if two reflection laser sensors are used, the presence or absence of the substrate can be determined based on the detection information of both sensors, so that the reliability of the substrate detection is high. invention).

[0014]

BEST MODE FOR CARRYING OUT THE INVENTION An apparatus for attaching an adhesive tape for protecting a surface to a semiconductor substrate before performing a back grinding process, or peeling an adhesive tape for protecting a surface from a semiconductor substrate after back grinding, is described below. An embodiment to which the present invention is applied will be described with reference to the drawings. FIG. 1 is a front view of the adhesive tape sticking / peeling apparatus, and FIG. 2 is a side view thereof.

On a processing table 1 of this apparatus, there are provided two cassette mounting tables 2 on which a cassette C containing a plurality of stacked semiconductor substrates (hereinafter abbreviated as substrates) W is positioned and mounted.
An air cylinder 3 for turning the same, a robot arm 4 for carrying out, moving up, down, and turning the substrate W one by one from the cassette C, and centering the substrate W supplied by the robot arm 4; An aligner 5 for correcting the orientation, a bonding table 6 for receiving and mounting the substrate W centered and corrected in the orientation of the aligner 5 are provided. Further, an adhesive tape attaching mechanism 8 for attaching an adhesive tape to the surface of the substrate W placed on the attaching table 6 is provided on the front surface of the vertical frame 7 erected on the back of the processing table 1. At the front end of the processing table 1 near the robot arm 4, a sensor mounting table 9 is erected via a stand 10, and a substrate detection sensor S is positioned and mounted on the sensor mounting table 9.

As shown in FIGS. 5 and 6, the substrate detection sensor S comprises a pair of reflective laser sensors 11 and a detection circuit unit 12 provided in a sensor case 13. The sensors 11 are arranged in parallel at a predetermined angle inward so that the laser light from the sensors 11 is focused and projected at one point. Also, two sets of positioning pins 1 are provided on the bottom of
4, 15 are protruded.

A pair of left and right ridges 16 are formed on the upper surface of the sensor mounting table 9, and a pair of outer positioning pins 14 formed on the bottom surface of the sensor case 13 are inserted into positioning holes 17 formed on the upper surface of the ridges 16. Is inserted, the substrate detecting sensor S can be positioned in a fixed posture and mounted and stored on the sensor mounting table 9.

As shown in FIG. 3, a pair of left and right locking holes 18 are formed at the tip of the robot arm 4. As shown in FIG. 6, the robot arm 4 is inserted between the left and right ridges 16 of the sensor mounting table 10 and raised to lock a pair of inner positioning pins 15 formed on the bottom surface of the sensor case 13. The substrate detection sensor S can be lifted from the sensor mounting table 9 and carried out in a state of being inserted and positioned in the hole 18. Note that the substrate detection sensor S and a detection circuit (not shown) are connected by an extendable coil-shaped cord 19 (FIG. 2).
reference).

Further, a control device for driving the robot arm 4 and the adhesive tape sticking mechanism 8 in a predetermined order and a cassette C detected by the substrate detection sensor S are provided below the processing table 1. And a storage device for storing the storage state of the substrate.

The substrate detecting apparatus according to the present embodiment is configured as described above, and the operation of the apparatus will be described below. First, the robot arm 4 advances toward the sensor mounting table 9. The robot arm 4 positions and holds the substrate detection sensor S via the positioning pins 15 and the locking holes 18. Subsequently, as shown in FIG. 4, the robot arm 4 moves the substrate detection sensor S to a predetermined position on the front of the cassette C. Then, as shown in FIG. 7, the robot arm 4 reciprocates the substrate detection sensor S up and down once in a state where the substrate detection sensor S faces the periphery of the group of substrates W stacked and accommodated, and then horizontally moves to another location. By making one round trip up and down,
The presence or absence of the substrate W and the stored state of the substrate are detected. Here, the reason why the substrate detection sensor S scans by reciprocating up and down once at substantially the same location is to increase the detection accuracy of the substrate. Also,
The scanning at the two right and left portions is for detecting whether or not the substrate W is inserted into the cassette C at an angle. Information on the presence or absence of a substrate in each groove in the cassette C is stored in a storage device provided in association with the control device.

When the detection process is completed, the robot arm 4
Is again moved onto the sensor mounting table 9, the substrate detection sensor S is positioned in the original state, and is returned and mounted.

Thereafter, the original substrate transfer operation by the robot arm 4 is performed. Specifically, the robot arm 4 takes out the substrate W from a predetermined groove in the cassette C and carries it into the aligner 5 by referring to the information on the presence or absence of the substrate stored in the storage device. The robot arm 4 receives the substrate W positioned by the aligner 5 and carries the substrate W onto the attaching table 6. The robot arm 4 receives the substrate W to which the adhesive tape has been attached by the adhesive tape attaching mechanism 8, and carries the substrate W into another cassette C.

The substrate detection operation and the substrate transfer operation by the robot arm 4 are controlled based on a preset program. When the size of the substrate W changes, the substrate held by the robot arm 4 is changed. The setting of the separation distance between the detection sensor S and the substrate W in the cassette C and the like may be switched to a program corresponding to the setting.

The present invention is not limited to the case where the adhesive tape is applied to the substrate W, the case where the applied adhesive tape is peeled off, or the case where the substrate W stored in the cassette C is
The present invention can be applied to various types of substrate processing apparatuses having a configuration in which the substrate is conveyed by using.

[0025]

As is apparent from the above description, the following effects can be expected from the method and apparatus for detecting a substrate in a cassette according to the present invention. (1) Since the substrate detection sensor is moved using the substrate transfer robot arm itself, the arm structure can be simplified as compared to a type in which a sensor holding arm is separately provided from the substrate transfer arm. The sensor holding arm does not become an obstacle during the original substrate transfer operation.

(2) When the robot arm operates to transfer the substrate, the sensor for detecting the substrate is stored at a predetermined position. Therefore, a sensor such as a type in which the arm for transferring the substrate and the sensor arm are operated integrally. The code derived from the arm is not swung with the operation of the arm, and the substrate transfer operation can be performed satisfactorily.

(3) In particular, if a reflection type laser sensor is used as the substrate detection sensor, the substrate position can be detected with extremely high sensitivity and accuracy by narrowing down the laser beam.

(4) In this case, if two reflection laser sensors are used, the reliability of detection is high.

[Brief description of the drawings]

FIG. 1 is an overall plan view of a substrate processing apparatus according to an embodiment.

FIG. 2 is an overall side view of the substrate processing apparatus.

FIG. 3 is a plan view showing a robot arm and a substrate detection sensor placed on a sensor mounting table.

FIG. 4 is a plan view of a main part showing a substrate detection operation state.

FIG. 5 is a perspective view showing a sensor mounting table and a substrate detection sensor.

FIG. 6 is a front view of a substrate detection sensor placed on a sensor mounting table.

FIG. 7 is a perspective view of a cassette containing substrates.

[Explanation of symbols]

 2 ... cassette mounting table 4 ... robot arm 9 ... sensor mounting table 11 ... reflective laser sensor C ... cassette S ... substrate detection sensor W ... substrate

Claims (4)

[Claims] 1. A substrate detection sensor stored and held at a predetermined position is held by a substrate transfer robot arm, and the robot arm is moved to detect a substrate contained in a cassette by the sensor. A method for detecting a substrate in a cassette, comprising: 2. A cassette mounting table for positioning and mounting a cassette, a robot arm for transporting a substrate for taking out a substrate stored in the cassette and transporting the substrate to a predetermined processing site, and a substrate detachably attached to a distal end of the robot arm A detection sensor, a sensor mounting table for positioning and mounting the substrate detection sensor detached from the robot arm, and a substrate detection sensor mounted on the sensor mounting table held by the robot arm and unloaded, and The robot moves the detection sensor to the position facing the cassette, moves the substrate stacked in the cassette in the stacking direction, and returns the substrate detection sensor to the sensor mounting table again after the detection operation is completed. A substrate detecting device in a cassette, comprising: control means for controlling movement of an arm. 3. The substrate detecting device in a cassette according to claim 2, wherein the substrate detecting sensor uses a reflection type laser sensor for detecting the substrate based on reflection of laser light projected toward an edge of the substrate. Substrate detection device in a cassette. 4. A substrate detecting device in a cassette according to claim 3, wherein two reflection type laser sensors are arranged in parallel as a substrate detecting sensor, and the same substrate is detected by both sensors. Substrate detection device in cassette.