JP7117837B2 - Locally clean substrate transfer device - Google Patents

Description

The present disclosure relates to a local clean substrate transfer apparatus that creates a local clean environment by blowing air with a fan filter unit and has a transfer robot inside the apparatus, and particularly mitigates the effects on the inside of the apparatus caused by movement of the transfer apparatus. It relates to a locally clean substrate transfer apparatus that

A locally clean substrate transfer apparatus used for manufacturing and inspecting semiconductors is provided with a transfer robot for transferring a substrate called a wafer, and a traveling apparatus for fixing and reciprocating the robot. In addition, in order to create a clean environment inside the locally clean substrate transfer device, clean air is constantly blown from the fan filter unit installed on the top of the device and exhausted from the exhaust port provided on the bottom of the device to form a down flow. , and maintains a more positive pressure than the outside of the device.

It is known that when the transfer robot moves to the end of the transfer track, it pushes out the air on the front side in the moving direction and hits the inner wall to generate turbulence in the downflow. Since there is a possibility that the foreign matter picked up by this disturbance adheres to the upper surface of the substrate, in order to suppress such adhesion of foreign matter, Patent Document 1 discloses that an opening is provided on the side surface of the local clean substrate transfer device, and the transfer robot is used to clean the substrate. A device is disclosed for discharging the forced air out of the device.

JP 2012-116647 A

In the configuration disclosed in Patent Document 1, it is necessary to provide an opening and an opening amount adjusting mechanism in the portion receiving the air pressure on the side surface of the local clean substrate transfer device, in order to prevent fine particles from flying up. However, even though it is outside the local clean substrate transfer apparatus, it is a clean room in a semiconductor manufacturing factory, and the exhaust gas from the apparatus should be properly treated under the floor. In addition, since the stagnation of the internal airflow cannot be suppressed in the opening on the side of the local clean substrate transfer device, it is conceivable that fine foreign matter that has not been discharged remains and is swirled up by changes in the air flow, for example, the turbulence, and adheres to the substrate. be done. Furthermore, it is necessary to maintain a positive pressure with respect to the outer space in order to suppress the intrusion of foreign substances from the outside into the conveying device. , it is difficult to properly suppress the rising of foreign matter caused by the local disturbance of the downflow.

The following aims to demonstrate high local cleaning performance by promoting clean air fluidization to airflow stagnant inside and suppressing the movement of the transfer robot without creating an opening on the side of the equipment housing. We propose a locally clean substrate transfer system for

As one aspect for achieving the above object, a transfer robot that reciprocates in the apparatus to transfer the substrate, a fan filter unit that supplies clean air filtered by a filter in the upper part of the apparatus, and a A local clean substrate transfer apparatus comprising a first exhaust port provided and a housing surrounding the transfer robot, the local clean substrate transfer apparatus having a movement locus end side of the transfer robot from the first exhaust port, wherein the A local clean board provided with a second exhaust port provided at the bottom of the device, an exhaust fan for exhausting gas in the device from the second exhaust port, and a control device for controlling the rotation speed of the exhaust fan. We propose a transport device.

According to the above configuration, it is possible to suppress the rising of the gas accompanying the movement of the transfer robot.

Schematic explanatory drawing of a locally clean board|substrate transfer apparatus. FIG. 4 is a diagram showing the positional relationship of the transfer robots in the locally clean substrate transfer device; FIG. 4 is a diagram showing the state of airflow in the locally clean substrate transfer device; FIG. 4 is a diagram showing the state of airflow in the locally clean substrate transfer device; FIG. 4 is a diagram showing the state of airflow in the locally clean substrate transfer device; FIG. 10 is a diagram showing an example of a locally clean substrate transfer apparatus equipped with a sensor for detecting the position of a transfer robot; FIG. 4 is a diagram showing the configuration of an exhaust fan;

The down flow in the locally clean substrate transfer apparatus will be described with reference to FIG. The locally clean substrate transfer device 101 forms a down flow with clean air from the fan filter unit 102 installed at the top and exhaust from the exhaust port 105 installed at the bottom of the device. is smaller than the housing 106 of the apparatus, it is difficult for clean air to reach the end of the inside of the apparatus, and stagnation 401 to 404 exist.

As shown in FIG. 2, the locally clean substrate transfer apparatus has a plurality of boxes containing substrates and devices 204 to 206 for opening and closing the boxes. It moves in front of the devices 204, 205, and 206 at high speed, picks up the substrates from this box, and transports them at high speed.

Movement of a foreign object caused by turbulence in airflow will be described with reference to FIG. When the transfer robot at the position indicated by the dotted line 103 moves to the position indicated by the solid line 202 at high speed, the downflow in the locally clean substrate transfer apparatus 101 is pushed forward in the moving direction of the transfer robot and collides with the inner wall of the side of the apparatus, resulting in disturbance 401 . ~404 are generated. It is conceivable that these disturbances 401 to 404 stir up minute foreign matter present on the inner walls and the lower part of the device, and the foreign matter adheres to the substrate.

In order to suppress the adhesion of foreign matter, the embodiments described below are mainly provided with a transfer robot that reciprocates in the apparatus to transfer the substrate, and the air from the fan filter unit installed in the upper part of the apparatus is blown to the lower surface of the apparatus. A local clean transport device that forms a downflow by exhausting air from an exhaust port provided in the transport robot, and has a fan provided at the transport track end of the transport robot and a function of controlling the rotation speed of the fan. When the robot stops or moves away from the transfer starting end, the fan rotation speed is lowered to promote fluidization of airflow stagnant in the equipment, and when the transfer robot approaches the transfer track end, the fan rotation speed is increased to push out. A locally clean substrate transport apparatus with fan control for exhausting trapped air is described.

According to the above configuration, when the transfer robot stops or moves away from the end of the transfer track, the rotation speed of the fan is lowered to fluidize the stagnation inside the apparatus, and the transfer robot moves by forming a down flow by discharging. When approaching the end of the transfer track, the rotation speed of the fan is increased to discharge the air pushed out by the transfer robot, thereby suppressing the soaring of fine foreign matter due to turbulence in the air flow and maintaining the down flow. High local clean performance can be achieved.

Hereinafter, a locally clean substrate transfer apparatus capable of suppressing foreign matter from flying up regardless of the movement of the transfer robot will be described with reference to the drawings.

FIG. 1 shows a schematic configuration of a locally clean substrate transfer apparatus. As shown in the plan view of FIG. 2, the locally clean substrate transfer apparatus 101 has one or more boxes capable of storing a plurality of substrates and devices 204, 205, and 206 for opening and closing the boxes, and stores a plurality of substrates. A transport robot 103 that takes out a substrate from a box and transports it to a predetermined position, and a pre-alignment device 203 that orients the substrate are provided. This pre-alignment device 203 may be omitted. The transfer robot 103 can reciprocate at high speed to take out substrates from boxes 204, 205 and 206 which can store a plurality of substrates.

FIG. 3 is a diagram showing the state of the internal airflow of the locally clean substrate transfer apparatus 101. FIG.

The clean air from the fan filter unit 102 installed on the top of the locally clean substrate transfer device 101 is exhausted from the exhaust port 105 (first exhaust port) provided on the bottom surface of the device. At this time, pressure is monitored by a pressure sensor 301 for monitoring the internal pressure of the local clean substrate transfer apparatus 101 and a pressure sensor 302 for monitoring the external pressure, and a fan is operated to keep the inside of the local clean substrate transfer apparatus 101 at a positive pressure. The air volume of the filter unit 102 is adjusted.

Fans 107 and 108 are provided at the end of the transfer robot transfer track inside the locally clean substrate transfer apparatus 101, which is a feature of this embodiment. Fans 107 and 108 are exhaust fans for exhausting the gas contained in the internal space of the local clean substrate transport apparatus 101, and extend from the exhaust port 105 to the edge of the movement locus of the transfer robot (an imaginary straight line extending the movement locus in the movement direction). The gas is exhausted from the exhaust ports 109 and 110 (second exhaust ports) provided on the lower surface of the local clean substrate transfer device 101 (on the upper wall side).

An example showing the structure of FIG. 7 for the fans 107 and 108 will be described in a three-dimensional view. The fan has rotary blades 701, a rotary shaft 702, a rotary motor 703, and a case 704 that surrounds them and forms an outer shape. By rotating the , an air flow is generated.

Fans 107 and 108 always rotate at a low rotational speed when the locally clean substrate transfer apparatus is in operation.

Due to the structure of the locally clean substrate transfer apparatus 101, the fan filter unit 102 is mounted with a smaller projection area than the locally clean substrate transfer apparatus housing 106. FIG. Therefore, the clean air does not reach the area outside the projection area of the fan filter unit inside the local clean substrate transfer apparatus, and stagnation occurs. to form a down flow throughout the interior of the housing. This effect is obtained when the robot is stopped.

FIG. 1 is a diagram showing the behavior of the fans 107 and 108 due to the reciprocating movement of the transfer robot 103 mounted on the locally clean substrate transfer apparatus 101. FIG.

When the transfer robot 103 moves to the position 202 and approaches the inner wall 111 (exhaust port 109), the rotation speed of the fan 107 is increased so that the air pushed out by the transfer robot 103 does not rise, and the local clean substrate transfer device is provided. is discharged to the outside of the device, here below the device. At this time, the fan 108 provided on the inner wall 112 side facing the fan 107 maintains a low rotational speed.

When the transfer robot has completed its operation at the position 202, the fan 107 whose rotation speed has been increased returns to its original low rotation speed with a time lag after the transfer robot stops. The time difference is, for example, 1 second later.

When the transfer robot moves away from the inner wall, the fan 107 maintains a low rotation speed. When the transfer robot approaches the opposing inner wall, the opposing fan 108 behaves similarly.

When the transport robot 103 is stopped regardless of the positions 201, 202, etc., the fans 107, 108 continue to maintain a low rotational speed.

In this way, when the transfer robot is stopped, the rotation speed of the fan is lowered to promote fluidization and discharge of the stagnation inside the local clean substrate transfer device, and when the transfer robot approaches the inner wall by the reciprocating motion, the rotation speed of the fan is increased. It is possible to maintain the downflow and internal positive pressure inside the locally clean substrate transfer apparatus by actively discharging the soaring to create a highly clean environment.

An embodiment in which the disk-shaped position information detector 606 is used to control the rotation speed of the fan will be described with reference to FIG.

FIG. 6 is a front view of the local clean substrate transfer device as seen from the front. The transfer robot 103 installed in the locally clean substrate transfer device 101 is moved by rotating a traveling shaft 604 by a motor 605, and moves between a box containing a plurality of substrates and devices 204, 205 for opening and closing the box. Move to position 206 . A disk-shaped position information detector 606 attached to the motor 605 constantly detects motor rotation position information, so that the controller 601 that controls the local clean substrate transfer device 101 monitors the position and controls the operation of the transfer robot.

As described above, the fans 107 and 108 have a function of generating an air flow by rotating the rotating shaft to which the rotating blades are attached by the rotating motor. The rotating motor can increase or decrease the number of revolutions according to an electric command from the control device 601 .

The position of the transport robot and the control of the fan will be explained. When the transfer robot 103 moves to 202 and approaches the inner wall, the control device 601 processes the position information from the disk-shaped position information detector 606 attached to the motor and the rotation direction of the motor 605, and rotates the rotating motor of the fan 107. is issued, the number of revolutions of the fan 107 is increased in accordance with the movement of the transfer robot. When the control device 601 detects that the transfer robot has stopped at 202, it issues an electrical command to the fan 107 to reduce the rotation speed of the fan. When the transfer robot moves away from the position 202 and leaves the inner wall, the control device 601 processes the position information from the disk-shaped position information detector 606 and the rotation direction of the motor 605, and issues an electric command to lower the rotation speed of the fan 107. By doing so, the rotation speed of the fan 107 remains low when the transfer robot moves away from the inner wall.

As a result, it is possible to create a highly clean environment by suppressing the movement of the transfer robot when it approaches the inner wall and maintaining the downflow when the transfer robot stops or leaves the inner wall.

Another embodiment of detecting the position information of the transport robot 103 installed in FIG. 6 and controlling the rotational speeds of the fans 107 and 108 will be described.

Instead of the disc-shaped position information detector 606 attached to the motor 605 in the second embodiment, this embodiment employs a linear position information detector 616 installed along the transport robot movement trajectory independently of the motor 605. use.

Position information obtained by directly detecting the position of the transfer robot by the linear position information detector 616 is taken into the control device 606, and the rotation direction and position information of the motor 605 are processed, thereby enabling control of the number of rotations of the fan 107. Performance equivalent to that of Example 2 can be obtained.

Another embodiment of detecting the position information of the transport robot 103 installed in FIG. 6 and controlling the rotational speeds of the fans 107 and 108 will be described.

As another means for detecting the position of the transfer robot 103 for controlling the rotation speed of the fan in the second and third embodiments, this embodiment uses position detection sensors 626 and 627 attached to the traveling shaft 604 .

The position detection sensors 626 and 627 directly detect the position of the transfer robot, the detection information is taken into the control device 606, and the rotation direction of the motor 605 and the detection information are processed, thereby controlling the number of rotations of the fan 107. , and performance equivalent to that of Examples 2 and 3 can be obtained.

Reference Signs List 101 Locally clean substrate transport device 102 Fan filter unit 103 Transport robot 104 Traveling device 105 Exhaust port provided on the bottom surface of locally clean substrate transport device 106 Locally clean substrate transfer device housing 107, 108 Fans 201, 202 Transfer robot movement position 203 Pre-alignment device 204, 205, 206 Plural substrates A box that can store a single sheet and an opening/closing device of the box 301...Internal pressure sensor 302...External pressure sensor 401-404...Stagnant flow 501-503...Rising flow 601... Control device 604 Travel axis 605 Motor 606 Disc-shaped position information detector 616 Linear position information detector 626, 627 Position detection sensor 701 . . Rotor wing 702 .. Rotating shaft 703 .. Rotating motor 704 .

Claims (6)

A transfer robot that reciprocates in the apparatus to transfer the substrate, a fan filter unit that supplies clean air filtered by a filter in the upper part of the apparatus, a first exhaust port provided in the lower part of the apparatus, and the transfer In a locally clean substrate transfer apparatus comprising a housing surrounding a robot,
a second exhaust port provided in a lower portion of the apparatus on the side of the movement locus end of the transfer robot from the first exhaust port; Equipped with a fan and a control device that controls the rotation speed of the exhaust fan,
The first exhaust port and the second exhaust port are formed on the floor of the apparatus ,
The locally clean substrate transfer apparatus , wherein the exhaust fan is located on the wall surface side of the locus of movement . In claim 1,
The local clean substrate transfer apparatus, wherein the control device controls the rotation speed of the fan according to the reciprocating movement of the transfer robot. In claim 1,
The local clean substrate transfer apparatus, wherein the control device controls the number of revolutions of the fan according to the position of the transfer robot. In claim 2 or 3,
The local clean substrate transfer apparatus, wherein the control device detects the position of the transfer robot and controls the rotation speed of the fan. In claim 1,
The control device increases the number of revolutions of the exhaust fan when the transfer robot moves closer to the second exhaust port than when the transfer robot is stopped. Substrate transfer device. In claim 5,
After the transfer robot has moved so as to approach the second exhaust port and after a predetermined time has elapsed after the transfer robot has stopped, the control device increases the rotation speed of the exhaust fan to the level before the increase. A local clean substrate transfer device characterized by returning to the rotational speed of .

Images