JP2000100903A - Substrate holding device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a substrate holding device the vacuum suction member of which can be exchanged easily with another one and which can surely prevent a falling member to be inspected. SOLUTION: Four suction pad groups 6 each of which is composed of suction pads 6a and 6b are arranged on a robot arm 5 in such a way that the groups 6 are separated from each other by prescribed distances and a glass substrate 3 is held by vacuum suction by means of one suction pads 6a of the groups 6. When one of the suction pads 6a causes leakage while the pads 6 hold the substrate 3 by vacuum suction, the pad 6 causing the leakage is switched to another suction pad 6b of the same group 6 by switching a solenoid valve 8a (8b, 8c, or 8d).

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a substrate holding apparatus for holding a substrate to be inspected, for example, a semiconductor wafer or a liquid crystal glass substrate of a flat display by vacuum suction.

[0002]

2. Description of the Related Art Conventionally, for example, in a manufacturing process of a glass substrate of a liquid crystal display, a visual inspection device has been used as a device for visually inspecting the surface of a glass substrate for scratches and dirt.

FIG. 8 shows an example of such an appearance inspection apparatus, in which a plurality of glass substrates 1 are placed on an apparatus main body 101.
02 is placed in the stacking direction, and a transfer arm 105 supported by an arm support portion 104 is provided corresponding to the cassette 103. First, the transfer arm 105 is inserted into the cassette 103. Then, the glass substrate 102 is vacuum-adsorbed and pulled out, and from this state, the glass substrate 102 is further moved to the inspection position by the transfer arm 105, and the glass substrate 102 is given a swinging or rotating motion, and the surface of the glass substrate 102 is The condition can be visually inspected from various directions.

In this case, the transfer arm 105 is provided with a mechanism that enables various movements for performing a swinging operation, a rotating operation, and the like in addition to an operation of taking out the glass substrate 102 from the cassette 103. Glass substrate 10
2 is, for example, a transfer arm 1 as shown in FIG.
In the state of being vacuum-sucked on the suction pad 106 of FIG. 05, the suction pad 106 is held in the horizontal direction, or is swung in the tilting direction with the arm support 104 as a fulcrum as shown in FIG. Various movements are given, for example, as shown in FIG.

[0005]

However, as described above, the glass substrate 10 is attached to the suction pad 106 of the transfer arm 105.
2 is vacuum-adsorbed and a visual inspection of the glass substrate 102 is performed while applying movement such as transfer, swing and rotation.
When the suction pad 106 leaks due to deterioration or the like in a state where 02 is held at a predetermined angle,
There is a possibility that the glass substrate 102 may fall from the transfer arm 105 and be damaged due to poor suction. Conventionally, in order to avoid such detachment of the suction pad 106 by suction, a worker judges a leak at the suction pad 106 from a leak sound, or the suction pad 1 before the substrate is sucked.
Inspections are conducted in advance to check that the surface of the suction pad does not have any scratches or deterioration. However, all of these methods require the worker to have detailed experience. It is necessary to perform a replacement operation, and therefore, there has been a problem that a series of work efficiency is greatly reduced, such as temporarily stopping a process of transporting the glass substrate 102 related to the inspection, such as the appearance inspection.

SUMMARY OF THE INVENTION The present invention has been made in view of the above circumstances, and has as its object to provide a substrate holding device that can easily replace a vacuum suction member and also reliably prevent a member to be inspected from dropping. And

[0007]

According to the first aspect of the present invention,
A substrate holding means for holding a plurality of vacuum suction member groups each including a plurality of vacuum suction members, and holding a substrate to be inspected by vacuum suction of at least one vacuum suction member of each of the vacuum suction member groups; Each of the vacuum suction members constituting the member group is constituted by vacuum suction member switching means which can be switched.

According to a second aspect of the present invention, in the first aspect of the present invention, the vacuum suction member is provided so as to be able to come into contact with and separate from the substrate to be inspected, and the vacuum suction member other than the one being used is the vacuum inspection member. It is characterized in that it stands by at a position away from the substrate.

According to a third aspect of the present invention, a plurality of vacuum suction member groups each including a plurality of vacuum suction members are provided, and at least one of the vacuum suction member groups is subjected to vacuum suction by a vacuum suction member. Substrate holding means for holding the vacuum suction member, pressure detection means for detecting a pressure required for vacuum suction of the vacuum suction member, and switching among the vacuum suction members constituting the vacuum suction member group based on a pressure detection result by the pressure detection means. It is constituted by the enabled vacuum suction member switching means.

As a result, according to the present invention, when a leak occurs in the vacuum suction member, it can be promptly replaced with another vacuum suction member. Further, according to the present invention, since the vacuum suction members other than those in use are separated from the substrate to be inspected and are on standby, the vacuum suction members can be replaced in a very short time without interrupting the transporting process. be able to.
Furthermore, according to the present invention, when a leak occurs in the vacuum suction member, the vacuum suction member can be automatically replaced without any trouble for the operator.

[0011]

Embodiments of the present invention will be described below with reference to the drawings. (First Embodiment) FIG. 1 shows a schematic configuration of a visual inspection apparatus to which the present invention is applied. In the figure, reference numeral 1 denotes a main body of a visual inspection apparatus, on which a cassette 2 is mounted.
Can be mounted. The cassette 2 accommodates, for example, a large number of 550 mm × 650 mm plate glass substrates 3 for a liquid crystal display in the laminating direction.

A robot arm 5 supported by a robot arm support unit 4 is provided as a substrate holding device so as to face the opening for loading and unloading the glass substrate 3 of the cassette 2. A plurality of robot arms 5 (four in the illustrated example)
And the suction pad group 6
Thus, the glass substrate 3 can be held by vacuum suction.

The robot arm support section 4 controls a series of movements of the robot arm 5 by a control section 7 arranged on the front panel of the apparatus main body 1. For example, the glass substrate 3 in the cassette 2 by the robot arm 5 is controlled. In and out,
Transfer of glass substrate 3 to inspection position, robot arm 5
Rocking in the direction in which the robot arm 5 moves, or rotation about the axis of the robot arm 5.

In this case, the control unit 7 is constituted by, for example, a system control unit of a personal computer of a display touch panel type and an operation unit. The control unit 7
An alarm device 701 that issues an alarm by sound or display to a worker when leak information is received from a pressure sensor 11, which will be described later, is disposed adjacent to the.

On the other hand, above the device body 1, a lighting device 8 is provided.
Is provided. This illumination device 8 is for visual inspection of the surface of the glass substrate 3. For example, illumination light from a 150 W metal halide lamp is suction-held by the robot arm 5 via a large Fresnel lens and is conveyed to the inspection position. The glass substrate 3 is illuminated.

FIG. 2 shows the relationship between the robot arm support section 4 and the robot arm 5 in more detail. The robot arm 5 is connected to the robot arm support section 4,
With this connection point as a fulcrum, a swinging operation in a tilting direction, a rotation operation about an arm axis, and a transfer operation for taking the glass substrate 3 in and out of the cassette 2 are enabled.

The robot arm 5 includes a suction pad group 6 composed of two suction pads 6a and 6b adjacent to each other.
Are separated by a predetermined distance and are arranged in four sets. And the suction pads 6a and 6b of one suction pad group 6 among these are
Each of them is connected to a switching solenoid valve 8a via a vacuum tube 7a, 7b, and one of the suction pads 6a, 6b is connected to a vacuum tube 9 to be described later so as to be suctionable by the switching electromagnet 8a. The remaining suction pads 6a and 6b of the suction pad group 6 also have vacuum tubes 7 respectively.
solenoid valves 8b, 8c, 8d which are switched via a and 7b separately.
Connected to. These solenoid valves 8a, 8b, 8c, 8d
Is connected to the above-described control unit 7 via control lines 13a, 13b, 13c, and 13d, respectively, and enables the control unit 7 to control the switching operation of each of the solenoid valves 8a, 8b, 8c, and 8d. I have.

These switching solenoid valves 8a, 8b, 8c, 8
d is connected to a vacuum source 10 via one vacuum tube 9. In the middle of the vacuum tube 9,
A pressure sensor 11 is provided near the vacuum source 10, and a buffer tank 12 is provided between the electromagnetic valves 8 a to 8 d and the pressure sensor 11. Here, the pressure sensor 1
1 is for detecting the pressure at the vacuum source 10.
Further, the buffer tank 12 maintains a pressure that guarantees vacuum suction in each suction pad group 6 for a certain period of time so that the suction capacity does not instantaneously decrease when the pressure of the vacuum generation source 10 suddenly increases. It is for.

FIGS. 3A and 3B show a schematic configuration of an example of the suction pads 6a (6b) of the suction pad group 6. FIG.
FIG. 3A shows a standby state, and FIG. 3B shows a use state. In this case, the robot arm 5 forms a hollow portion between the arm lower surface 51 and the arm upper surface 52,
A vacuum chuck 61 is provided on the arm lower surface 51 in this hollow portion.
A suction pad main body 62 is provided through the base member, and a substrate suction and non-suction state can be obtained by air pressurized and depressurized through a vacuum pipe 63 disposed through the arm lower surface 51. A plurality of electromagnets 64 are provided on the arm lower surface 51 around the vacuum chuck 61.
A magnetic body 65 made of, for example, a metal is arranged in the suction pad main body 62 corresponding to the above. Then, the arm lower surface 51
The magnetic body 65 is attracted to the electromagnet 64 against the repulsive force of the vacuum chuck 61 by urging the electromagnet 64 through the wiring 66 disposed through the wire, as shown in FIG. The suction pad main body 62 is maintained in a state where it is positioned substantially flush with the arm upper surface 52 (to the extent that the substrate back surface does not contact the arm upper surface 52). When one of the suction pads 6a of each suction pad group 6 is selected by switching the solenoid valves 8a, 8b, 8c, 8d by the control unit 7, the electromagnet 64 on the side selected by the control unit 7 is turned off. Urged by the repulsive force of the vacuum chuck 61 itself.
Is maintained in a state protruding from the arm upper surface 52 as shown in FIG.

Next, the operation of the embodiment configured as described above will be described. Now, when inspecting the glass substrate 3,
First, the robot arm 5 is inserted through the substrate loading / unloading opening of the cassette 2, and the glass substrate 3 is held by one of the suction pads 6 a maintained in use in each suction pad group 6 by vacuum suction. The robot arm 5 is conveyed to an inspection position illuminated by 8, and the robot arm 5 swings or rotates the robot arm 5 at this position to visually inspect the front or back surface of the glass substrate 3. In this case, if no pressure abnormality occurs in the suction pads 6a (6b) of the suction pad group 6 of the robot arm 5, the glass substrate 3 subjected to the normal appearance inspection is again transferred into the cassette 2 by the robot arm 5. Is returned to the original position.

Next, in the inspection process of the glass substrate 3, or in a transport process related to the inspection, the suction pads 6a of the suction pad group 6 of the robot arm 5 that vacuum sucks the glass substrate 3 are provided.
Leakage occurs due to damage or deterioration of the glass, or foreign matter intervenes between the suction pad 6a and the glass substrate 3, so that the degree of adsorption to the suction surface of the glass substrate 3 is reduced and leakage occurs. In such a case, a switching command is input from the display touch panel of the control unit 7 to the solenoid valve 8a corresponding to the suction pad group 6 in which the suction abnormality has occurred. Then, the electromagnet 64 of the suction pad 6b maintained in the other standby state of the suction pad group 6 is deenergized by a command from the control unit 7, and the vacuum chuck 61 protrudes from the arm upper surface 52 and is maintained in use. At the same time, the electromagnetic valve 8a is switched to switch from the suction pad 6a in which the leak is occurring to the spare suction pad 6b. At the same time when the switching of the solenoid valve 8a is completed, the suction pad 6a having the leak
Is energized, and is maintained in a standby state as shown in FIG.

Accordingly, if a leak occurs in the suction pads 6a (6b) of the suction pad group 6, the replacement of the suction pads can be performed only by the switching command by the operator. Even during the transfer, the other suction pads 6 are instantly provided without interrupting the transfer process.
b (6a), and the work efficiency can be improved. In the standby state, the glass substrate 3
Since it is separated from the substrate, unnecessary contact of the spare suction pad with the substrate is eliminated, and there is no possibility that dirt adheres to the substrate or durability of the preliminary suction pad is deteriorated. Further, by detecting the suction abnormality due to the leak, notifying the worker, and individually switching each of the solenoid valves 8a to 8d, the occurrence of the leak can be easily found. (Second Embodiment) FIGS. 4A and 4B show a schematic configuration of another example of the suction pads 6a (6b) of the suction pad group 6, and the same parts as those in FIG. Is attached.

FIG. 4A shows a standby state,
(B) shows a use state. In this case as well, the robot arm 5 forms a hollow portion between the arm lower surface 51 and the arm upper surface 52. A suction pad main body 72 is provided on the lower surface 51 of the arm in the hollow portion via a vacuum chuck 71, and the substrate is suctioned and unloaded by air that is pressurized and depressurized through a vacuum pipe 73 disposed through the lower surface 51 of the arm. An adsorption state is obtained. Further, a plurality of vacuum chucks 74 for maintaining the suction pad main body 72 in a standby state are disposed between the arm lower surface 51 and the suction pad main body 72, and a vacuum pipe 75 disposed through the arm lower surface 51. With air depressurized through
Suction pad body 72 against the repulsive force of vacuum chuck 71
Is moved downward, and the standby suction pad main body 72 is maintained in a standby state substantially flush with the upper surface 52 of the arm (to the extent that the back surface of the substrate does not contact the upper surface 52 of the arm). Further, when the vacuum chuck 74 is released to the atmospheric pressure through the vacuum pipe 75, the suction pad main body 72 moves upward due to the repulsive force of the vacuum chucks 71 and 74, and FIG.
As shown in FIG. 8, the use state slightly protruding from the arm upper surface 52 is maintained.

Therefore, the suction pad 6a (6
Even if the suction pad group 6 having the condition (b) is adopted, the leakage of the suction pads 6a (6b) is caused, and at the same time, by switching from one suction pad 6a to the other suction pad 6b,
The same effect as in the first embodiment can be expected. (Third Embodiment) FIG. 5 shows a schematic configuration of a third embodiment of the present invention, and the same parts as those in FIG. 1 are denoted by the same reference numerals.

FIG. 5 illustrates the relationship between the robot arm support 4 and the robot arm 5 in detail. In this case, the suction pad group 6 provided on the robot arm 5 includes three suction pads 6a, 6b, 6c. Consists of These suction pads 6a, 6b, 6c are arranged on a pad supporting member 15, and four such pad supporting members 15 are arranged on the robot arm 5.

The pad supporting members 15 are provided so that the suction pads 6a, 6b, and 6c can be switched. Each pad supporting member 15 has a vacuum tube 16a,
6b, 16c and 16 are connected, and these vacuum tubes 1
6 a, 16 b, 16 c, and 16 d are integrated into one and connected to a vacuum source 10 via a vacuum tube 9.

A pressure sensor 11 is provided in the middle of the vacuum tube 9 in close proximity to a vacuum source 10, and a buffer tank 12 is provided between the robot arm support 4 and the pressure sensor 11.

FIG. 6 shows a schematic configuration of the pad support member 15, in which suction pads 6a, 6b, 6c are arranged at equal intervals along the circumferential direction on the upper side of a disk-shaped main body 151. I have. The upper side of the main body 151 is rotatable about a central axis 152. In this case, the rotating method of the main body 151 is performed manually or by operating a control unit 7 by providing a driving mechanism such as a flat motor or an ultrasonic motor. One vacuum tube 16a (16b, 16c, 16d) is connected to the lower side of the main body 151, and the suction pad 6a,
Either 6b or 6c is connected to the vacuum tube 16a (16b,
16c, 16d), the selected suction pad 6a is connected to the vacuum tube 1 in the illustrated example.
6a and is maintained in use. The other suction pads 16b, 16c, and 16d are separated from the vacuum tube 16a as spares and are kept in a standby state.

The specific structure of the suction pads 6a, 6b and 6c is the same as that shown in FIGS. 3 and 4. According to such a configuration, when a worker finds a leak in any one of the suction pad groups 6 in the inspection or the substrate transport process related to the inspection, for example, the suction pads 6a in a certain suction pad group 6 In this case, the operator returns the substrate to the cassette, rotates the main body 151 of the pad support member 15, and removes the suction pad 6b or 6c for spare from the vacuum tube 16a (16b). , 16c, 16d), the pads can be replaced in a very short time. When the main body 151 is rotated by electric power, the suction pad 6a on the main body 151 in which the leak has occurred is separated from the glass substrate, for example, as shown in FIG. If the rotation of the upper side of 151 is controlled to switch to another suction pad 6b, the suction pad can be replaced without interrupting the work such as the substrate transfer process. (Fourth Embodiment) FIG. 7 shows a schematic configuration of a fourth embodiment of the present invention, and the same parts as those in FIG. 1 are denoted by the same reference numerals.

FIG. 7 shows the relationship between the robot arm support 4 and the robot arm 5 in detail, and
Can be automatically switched over.

In this case, the switching solenoid valves 8a, 8b, 8
c and 8d are vacuum tubes 17a, 17b and 1 respectively.
7c, 17d, the pressure sensors 18a, 18b, 18
c and 18d are connected. These pressure sensors 18a,
18b, 18c and 18d detect the pressure at the suction pads 6a (6b) of each suction pad group 6, and include, for example,
It is possible to detect -60 kPa as a pressure value at the time of normal suction and -40 kPa as an abnormal pressure value at the time of leak, and to output these detection outputs to signal lines 19a, 19b, 19c,
19d is output to the control unit 7 via each of them.

The pressure sensors 18a, 18
b, 18c, 18d are connected to a vacuum source 10 via one vacuum tube 9. A pressure sensor 11 is provided in the middle of the vacuum tube 9 in close proximity to the vacuum source 10, and a buffer tank 12 is provided between the electromagnetic valves 8 a to 8 d and the pressure sensor 11.

According to such a configuration, in the inspection or the substrate transporting process involved in the inspection, the pressure of the suction pads 6a (6b) of each suction pad group 6 is constantly measured by the pressure sensor 1
8a, 18b, 18c and 18d.
When a leak occurs in any of the suction pad groups 6, the leak is caused by the pressure sensors 18a, 18b,
Judgment is made based on detection signals of abnormal pressure values from 18c and 18d. For example, when a detection signal of an abnormal pressure value is output from the signal line 19a from the pressure sensor 18a while the substrate is being sucked by the suction pads 6a of the suction pad group 6, the control unit 7 issues an alarm to the alarm device 701 and Then, the electromagnetic valve 8a is switched to automatically switch to the suction pad 6b.

Accordingly, if a leak occurs in the suction pads 6a (6b) of the suction pad group 6, the suction pads can be automatically replaced without any trouble for the operator. In addition, the burden on the operator can be reduced, and the inspection and the substrate transport process related to the inspection can be continued, so that the efficiency of these operations can be dramatically improved. In addition, since the suction pad is replaced immediately upon occurrence of a leak in the suction pad 6a (6b), the substrate can be prevented from dropping, and the substrate can be prevented from being damaged due to the drop.

[0035]

As described above, according to the present invention, when a leak occurs in the vacuum suction member, it can be promptly replaced with a spare vacuum suction member, and the vacuum suction can be performed by remote operation. By making the members exchangeable, the vacuum suction member can be exchanged without interrupting a series of operation steps related to inspection and the like, so that the efficiency of these operations can be dramatically improved.

Further, by holding the unused vacuum suction member at a position separated from the substrate to be inspected, contamination of the substrate by the vacuum suction member in the standby state can be prevented, and the durability of these vacuum suction members is deteriorated. I won't let you.

[Brief description of the drawings]

FIG. 1 is a diagram showing a schematic configuration of a visual inspection apparatus to which a first embodiment of the present invention is applied;

FIG. 2 is a diagram illustrating a schematic configuration of the substrate holding device according to the first embodiment.

FIG. 3 is a diagram showing a schematic configuration of a suction pad used in the first embodiment.

FIG. 4 is a diagram showing a schematic configuration of a suction pad used in a second embodiment of the present invention.

FIG. 5 is a diagram showing a schematic configuration of a suction pad used in a third embodiment of the present invention.

FIG. 6 is a diagram showing a schematic configuration of a pad supporting member used in a fourth embodiment.

FIG. 7 is a diagram showing a schematic configuration of a suction pad used in a fourth embodiment of the present invention.

FIG. 8 is a diagram showing a schematic configuration of a conventional visual inspection device.

FIG. 9 is a view for explaining the movement of a transfer arm of the conventional visual inspection device.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Device main body 2 ... Cassette 3 ... Glass substrate 4 ... Robot arm support part 5 ... Robot arm 6 ... Suction pad group 6a ... Suction pad 6b ... Suction pad 7 ... Control part 701 ... Alarm device 8 ... Illumination device 7a. 7b Vacuum tube 8a-8d Solenoid valve 13a-13b Control line 9 Vacuum tube 10 Vacuum source 11 Pressure sensor 12 Buffer tank 51 Arm lower surface 52 Arm upper surface 61 Vacuum chuck 62 Suction pad body 63 ... vacuum pipe 64 ... electromagnet 65 ... magnetic body 66 ... wiring 71 ... vacuum chuck 72 ... suction pad body 73 ... vacuum pipe 74 ... vacuum chuck 75 ... vacuum pipe 15 ... pad support member 151 ... body 152 ... central axis 16a to 16d ... Vacuum tubes 17a-17d ... Vacuum tubes 18a-18d ... Pressure sensors 19a-19d ... Signal lines

Claims (3)

[Claims] 1. A substrate holding means having a plurality of vacuum suction member groups each including a plurality of vacuum suction members, and holding a substrate to be inspected by vacuum suction of at least one vacuum suction member of each of the vacuum suction member groups. A substrate holding device, comprising: a vacuum suction member switching unit configured to switch each vacuum suction member constituting the vacuum suction member group. 2. The vacuum suction member is provided so as to be capable of coming into contact with and separating from the substrate to be inspected.
2. The substrate holding device according to claim 1, wherein the substrate holding device is placed at a position distant from the substrate to be inspected. 3. A substrate holding means having a plurality of vacuum suction member groups each including a plurality of vacuum suction members, and holding a substrate to be inspected by vacuum suction of at least one vacuum suction member of each of the vacuum suction member groups. Pressure detecting means for detecting a pressure required for vacuum suction of the vacuum suction member, and a vacuum suction member capable of switching each vacuum suction member constituting the vacuum suction member group based on a result of pressure detection by the pressure detection means. A substrate holding device comprising switching means.