KR20110062522A - Substrate transfer apparatus and method for transferring substrates therefo - Google Patents

Abstract

PURPOSE: An apparatus for transferring a wafer and a method for transferring the wafer using the same are provided to prevent the generation and the damage of scratches on the wafer by adjusting the operation of a transferring robot. CONSTITUTION: A transferring robot(140) includes at least one robot arm drawing a wafer from a cassette containing a plurality of wafers. A plurality of sensors(130, 132) acquires mapping information with respect to the wafers contained in the cassette. A controlling part(150) verifies the position and the tilted angle of the wafers to adjust the operation of the robot arm. The wafer is drawn from the cassette based on the operation of the robot arm.

Description

Substrate transfer apparatus and its substrate transfer method {SUBSTRATE TRANSFER APPARATUS AND METHOD FOR TRANSFERRING SUBSTRATES THEREFO}

The present invention relates to a substrate transfer apparatus, and more particularly, to a substrate transfer apparatus and a method for correcting the operation of the transfer robot in order to take out at least one wafer loaded obliquely in the cassette.

In order to provide a semiconductor device, a substrate processing apparatus for processing a wafer substrate protects the wafer from foreign substances or chemical contamination in the air, and uses a closed wafer container such as a cassette or a carrier to store and transport the wafer. Front Open Unified Pod (FOUP) is mainly used as a representative example of such a sealed wafer container. The substrate processing apparatus also provides an index such as an equipment front end module (EFEM) that serves as an interface between the cassette and the processing apparatus for processing the process. The index is provided with a substrate transfer device, which transfers the substrate between the cassette and the processing device.

When the cassette in which the wafer is stored is mounted in the load port of the substrate processing apparatus, the load port proceeds to identify the number, location, etc. of the wafers stored in the cassette. This is called mapping, and the wafer stored in the cassette This mapping information is obtained using sensors that sense the location of the device.

Generally, a cassette loads a plurality of wafers, and the gap between the loaded wafers is very small for the purpose of increasing the wafer acceptance rate. Therefore, when the wafer is pulled in and taken out, it is difficult to accurately insert the wafer into or out of the wafer or to accurately find and withdraw the wafer. Accordingly, the position of each wafer is accurately detected using a mapping bar provided with sensors.

However, the substrate transfer apparatus which takes out a substrate using such mapping information cannot pull out a wafer corresponding to the state of the wafer loaded in a cassette. As a result, the robot arm of the substrate transfer device comes into contact with the wafer to cause scratches on the surface of the wafer or to collide with the wafer to break the wafer.

It is an object of the present invention to provide a substrate transfer apparatus and a method for withdrawing a wafer from a cassette.

Another object of the present invention is to provide a substrate transfer apparatus and method for determining the loading state of a wafer at the time of taking out the wafer from the cassette and correcting the takeout operation.

It is still another object of the present invention to provide a substrate transfer apparatus and method for preventing scratches and breakage of a wafer when taking out a wafer from a cassette.

In order to achieve the above objects, the substrate transfer apparatus of the present invention is characterized by correcting the operation of the transfer robot to take out the wafer in correspondence with the loading state of the wafer loaded in the cassette by using the mapping information. Such a substrate transfer device makes it possible to prevent scratches and breakage of the wafer when the wafer is taken out from the cassette.

A substrate transfer apparatus of the present invention according to this aspect includes: a transfer robot having at least one robot arm for taking out a wafer from a cassette on which a plurality of wafers are loaded; A plurality of sensors for obtaining mapping information for wafers loaded in the cassette; From the mapping information, the position and the degree of inclination of the at least one wafer loaded inclined from among the wafers loaded in the cassette are determined, and the movement operation of the transfer robot is corrected in response to the inclined degree, so that the at least one And a controller for controlling the wafer to be withdrawn from the cassette.

In one embodiment, the sensors detect the degree of inclination forward with respect to the extraction direction of the wafers loaded in the cassette and provide the mapping information.

In another embodiment, the control unit; If there is only one wafer loaded at an angle among the wafers loaded in the cassette, the transfer robot is moved by correcting the position of the entry into the cassette.

In another embodiment, the control unit; When a plurality of wafers loaded at an angle among the wafers loaded in the cassette are continuous, when the wafers of the highest or lowest previous position among the loaded wafers are drawn out, the entry height into the cassette and the Position transfer is corrected to move the transfer robot.

According to another feature of the present invention, a substrate transfer method of a substrate transfer apparatus is provided. According to this method, the position and inclination of at least one wafer loaded at an angle among the wafers loaded in the cassette are determined, and the movement motion of the transfer robot is corrected according to the inclination degree.

In the substrate transfer method according to this aspect, mapping information is obtained from a cassette on which a plurality of wafers are loaded. From the mapping information, the position and the degree of inclination of at least one inclined wafer among the wafers loaded in the cassette are determined. Subsequently, the movement of the transfer robot is corrected corresponding to the position and the inclination degree, and the wafer is taken out from the cassette.

In one embodiment, determining the degree of inclination; The degree of inclination is determined by calculating a time difference detected from a plurality of sensors that obtain the mapping information.

In another embodiment, determining the inclination degree; From the cassette, it is determined that the transfer robot is inclined forward.

In another embodiment, correcting the movement of the transfer robot; If there is only one wafer loaded at an angle among the wafers loaded in the cassette, the transfer robot is moved by correcting the position of the entry into the cassette.

In another embodiment, correcting the movement of the transfer robot; When a plurality of wafers inclinedly stacked among the wafers loaded in the cassette are continuous, when the wafers of the highest or lowest previous position among the tiltedly stacked wafers are taken out, the entry height into the cassette and the Position transfer is corrected to move the transfer robot.

In yet another embodiment, withdrawing a wafer from the cassette; When the transfer robot picks up the wafer, the corrected movement of the transfer robot is moved in the reverse order.

As described above, the substrate processing apparatus of the present invention corrects and controls the operation of the transfer robot to take out the wafer according to the loading state of the wafer loaded on the cassette by using mapping information, thereby scratching the wafer when the wafer is taken out from the cassette. Occurrence and breakage can be prevented.

The embodiments of the present invention may be modified in various forms, and the scope of the present invention should not be interpreted as being limited by the embodiments described below. This embodiment is provided to more completely explain the present invention to those skilled in the art. Therefore, the shapes and the like of the components in the drawings are exaggerated in order to emphasize a clearer explanation.

Hereinafter, embodiments of the present invention will be described in detail with reference to FIGS. 1 to 6.

1 is a view showing a part of the configuration of a substrate processing apparatus according to the present invention.

Referring to FIG. 1, the substrate processing apparatus 2 includes at least one load port 120 on which a cassette (or carrier) 110 on which a plurality of wafers W are loaded is placed, and a processing unit for processing a process ( 104 and an index 102 disposed between the load port 120 and the processing unit 104 to transfer the wafer W between the cassette 110 and the processing unit 104.

Cassette 110 is provided, for example, in a FOUP. The cassette 110 provides a plurality of slots (112 in FIG. 2) which are installed in parallel to the top and bottom of the inner wall to load the wafers W, respectively, and are arranged at regular intervals. Slots 112 are inserted into a portion of the edge of the wafer (W).

The index 102 is provided as, for example, an Equipment Front End Module (EFEM), and includes a door 106 provided on a side wall facing the front surface of the cassette 110 mounted on the load port 120, and an inner bottom portion thereof. The door opener 108 is provided to open and close the door 106. The index 102 also includes a transfer robot 140 having at least one robot arm 142 for transferring the wafer W between the cassette 110 and the processing unit 104.

In addition, the index 102 is installed at the top to introduce external air to maintain a constant internal air cleanliness, and installed at the bottom to exhaust the internal air to the outside (for example, fans, filters, Pump, intake port and exhaust port).

The processing unit 104 receives the wafer W from the transfer robot 140 and processes the process. Although not shown in the drawings, the processor 104 may include a plurality of chambers, for example, a load lock chamber, a transfer chamber, a process chamber, or the like, or include a plurality of process chambers disposed at both sides of the transfer passage.

In the substrate transfer apparatus 100 of the present invention, when the wafer W is withdrawn from the cassette 110, in order to prevent contact and collision with the wafer W, the substrate transfer apparatus 100 of each wafer W loaded on the cassette 110 is provided. The withdrawal operation of the transfer device 140 is corrected in response to the loaded state.

Specifically, the configuration and operation of the substrate transfer apparatus for correcting the withdrawal operation of the transfer apparatus 140 are as follows.

2 and 3 are views showing the configuration of the substrate transfer apparatus shown in FIG. 1.

2 and 3, the substrate transfer apparatus 100 includes a transfer robot 140 having at least one robot arm 142 that pulls out the wafer W from the cassette 110, and a plurality of sensor units ( 130 and 132, and a controller 150 for controlling overall operations of the substrate transfer apparatus 100. The controller 150 includes a load port controller 122 and a robot controller 144.

The transfer robot 140 is provided, for example, with two robot arms 142 disposed up and down. At this time, each robot arm 142 is moved individually under the control of the robot controller 144. When the transfer robot 140 draws the wafer W into the cassette 110 or draws the wafer W out of the cassette 110, the transfer robot 140 is linearly moved in the front, rear, left, and right directions by the driving device 146, Rotate in the left and right direction. In addition, the driving device 146 drives the robot arms 142 individually under the control of the robot controller 144.

The sensor units 130 and 132 include first and second sensor units 130 and 132 which sense the wafers W loaded on the cassette 110 to obtain mapping information 124. For example, the first and second sensor units 130 and 132 are provided with mapping bars having a plurality of sensors. Each of the first and second sensor units 130 and 132 includes at least one light emitting and receiving light sensor, and is disposed on the front and / or rear sides of the cassette 110. The first and second sensor units 130 and 132 measure the degree of inclination toward the front of the direction in which the wafers W loaded on the cassette 110 are drawn out. This calculates the time difference between the first and second sensor units 130 and 132 to detect the inclined wafer W, and determines the degree of inclination using the same. The mapping information 124 includes various information about the number, position, and degree of inclination of the wafer W loaded on the cassette 110.

Mapping information 124 obtained from the first and second sensor units 130 and 132 is stored in a memory (not shown) of the load port controller 122. That is, when the cassette 110 is mounted in the load port 12, the door opener 108 opens the door 106 under the control of the load port controller 122. In this case, the first and second sensor units 130 and 132 detect the number, position, and inclination of the wafers W loaded on the cassette 110 to obtain mapping information 124, and load port information thereof. Provided to the control unit 122. Of course, the mapping information 124 may be directly provided to the robot controller 144 from the first and second sensor units 130 and 132.

The load port controller 122 controls the first and second sensor units 130 and 132 to obtain mapping information 124 and stores the obtained mapping information 124 in a memory (not shown). The load port controller 122 is connected to the robot controller 144 through a network, for example, a serial communication interface.

The robot controller (TMC) 144 receives the mapping information 124 from the load port controller 122 to tilt the front of the wafers W loaded on the cassette 110. Tilt information indicating the positions of the W2 to W4 and the degree of tilt thereof in FIGS. 4 and 5 is calculated to control the wafer extraction operation of the robot arm 142.

As illustrated in FIG. 4, the robot controller 144 may correct the position of the entry height into the cassette 110 when the wafer W2 is tilted and loaded among the wafers W loaded on the cassette 110. To move the transfer robot 140. In addition, as shown in FIG. 5, when the plurality of wafers W2 to W4 stacked inclined among the wafers W loaded on the cassette 110 are continuous, the robot controller 144 is tilted and stacked. When taking out the wafers W2 and W3 at the uppermost to the lowest previous positions among the wafers W2 to W4, the transfer robot 140 is moved by correcting the position of the entry into the cassette 110 and the degree of inclination. At this time, the wafer W4 at the lowest position is inclined to move the transfer robot 140 in the same manner as when only one wafer is loaded. The control operation of the robot controller 144 and the load port controller 122 may be processed by one controller 150.

Of course, when the tilted wafer is tilted to a degree that cannot be taken out by the robot arm 142, the robot control unit 144 cannot correct the position of the robot arm 142, so that the wafer withdrawal is stopped. Generate an alarm to the outside.

As described above, the substrate transfer apparatus 100 of the present invention is inclined from the mapping information 124 of the wafers W loaded on the cassette 110, and the position and inclination of the loaded wafers W2 and W3. Is calculated to correct the movement of the transfer robot 140 at the time of wafer pickup.

6 is a flowchart showing an operation procedure of the substrate transfer apparatus according to the present invention. 4 and 5, the wafer pick-up operation of the substrate transfer apparatus will be described.

Referring to FIG. 6, the wafers W loaded on the cassette 110 are sensed in step S200. That is, when the cassette 110 is mounted in the load port 120, the door 106 is opened by the door opener 108, and then the first and second sensor units 130 and 132 are inside the cassette 110. The mapping information 124 is obtained by measuring the number, position, and wafer loading state of the wafer W loaded in the plurality of slots 112 formed in the plurality of slots 112. The mapping information 124 obtained in step S210 is provided to the load port controller 122 and stored in a memory (not shown).

In operation S220, the mapping information 124 is provided from the load port control unit 122 to the robot control unit 144, and the robot control unit 144 receives the mapping information 124 and at least one of the wafer loading state, that is, the cassette 110. It is discriminated whether or not the wafer W is inclined in the forward direction. This occurs when the wafers W loaded in the slot 112 while the cassette 110 is transferred out of the horizontal state. In this case, during the mapping process, the first and second sensor units 130 and 132 measure inclination information indicating the degree of inclination of the wafer shifted forward from the correct position in the slot 112 and included in the mapping information 124. Let's do it.

As a result of the determination, if at least one wafer W is inclined forward, the procedure proceeds to step S230. That is, in step S230, the robot controller 144 determines the positions of the inclined wafers (W2 and W3 in FIGS. 4 and 5) using the mapping information 124, and in step S240, the robot controller 144 determines the first and second sensor units ( Wafer sensing time differences of the 130 and 132 are calculated to calculate the degree of inclination with respect to the wafers W2 and W3 at the corresponding positions.

Corresponding to the degree of inclination in step S250, the robot controller 144 corrects the movement position of the robot arm 142 to move the wafers W2 and W3 to be taken out. At this time, the robot control unit 144 stops the wafer withdrawal and generates an alarm to the outside, when the tilted degree is inclined to the degree that the robot arm 142 cannot pull out. Subsequently, in step S260, the robot arm 142 safely picks up the wafers W2 and W3 without contacting and colliding with the wafers W2 and W3 which are inclined forward, and again moves the robot arm 142 in the reverse order of the corrected pickup operation. The wafers W2 and W3 are taken out to complete the movement.

For example, as shown in FIG. 4, when one wafer W2 loaded in the cassette 110 is inclined forward, the wafer W2 at the corresponding position is normally used by using the mapping information 124. The entry position of the robot arm 142b is corrected to move the height below the cassette entry position of the robot arm 142a by a load, and the wafer W2 is moved forward and upward at the corrected entry position. Pick up. Subsequently, when the wafer W2 is picked up by the robot arm 142b, the robot arm 142b is lowered, moved backward, and ascended up by a to return to the robot arm 142b. Here, the corrected entry height a is made in a section between the inclined wafer W2 and the wafer located directly below.

In addition, as shown in FIG. 5, when the plurality of wafers W2 to W4 stacked on the cassette 110 are continuously inclined forward, the uppermost to among the wafers W2 to W4 loaded at an angle. The entry position of the robot arm 142c is corrected to move the height lower than a cassette entry position of the robot arm 142a when each of the wafers W2 and W3 at the lowest previous position are normally loaded and corrected. It moves forward from the entry position to a position that is not in contact with the wafers W2 and W3 (for example, a position entering between adjacent wafers up and down). Subsequently, the robot arm 142c is repeatedly synchronized with the forward and upward movements in response to the inclination information, and the wafers W2 and W3 are picked up by correcting the entry trajectory to move along the oblique line inclined by b from the forward trajectory. Subsequently, when the wafers W2 and W3 are picked up by the robot arm 142c, the robot arm 142c repeatedly moves downward and backward along the inclined diagonal lines as opposed to the movement of the robot arm 142c to enter between the wafers vertically adjacent to each other. The robot arm 142c is returned by reversing and rising upward by a again. The wafer W4 at the lowest position among the tilted stacked wafers W2 to W4 draws the wafer W4 by correcting the movement of the robot arm in the same manner as the position correction process shown in FIG. 4.

In the above, the configuration and operation of the substrate transfer apparatus according to the present invention is shown in accordance with the detailed description and drawings, but this is merely described by way of example, and various changes and modifications may be made without departing from the spirit of the present invention. It is possible.

1 shows a schematic configuration of a substrate processing apparatus according to the present invention;

2 is a perspective view showing a part of the configuration of the substrate transfer apparatus according to the present invention;

3 is a block diagram showing a configuration of the substrate transfer apparatus shown in FIG. 2;

4 and 5 are diagrams for explaining the wafer pick-up operation of the substrate transfer apparatus shown in FIG. And

6 is a flowchart illustrating a wafer take-out operation procedure of the substrate transfer apparatus according to the present invention.

Description of the Related Art [0002]

2: substrate processing apparatus 100: substrate transfer apparatus

110: cassette 124: mapping information

130, 132: sensor unit 140: transfer robot

142: robot arm 150: control unit

Claims (10)

In the substrate transfer device: A transfer robot having at least one robot arm for taking out a wafer from a cassette on which a plurality of wafers are loaded; A plurality of sensors for obtaining mapping information for wafers loaded in the cassette; From the mapping information, the position and the degree of inclination of the at least one wafer loaded inclined from among the wafers loaded in the cassette are determined, and the movement operation of the transfer robot is corrected in response to the inclined degree, so that the at least one And a controller for controlling the wafer to be withdrawn from the cassette. The method of claim 1, And the sensors detect the degree of inclination forward with respect to the extraction direction of wafers loaded in the cassette and provide the mapping information to the mapping information. The method according to claim 1 or 2, The control unit; And one of the wafers loaded at an angle to one of the wafers loaded in the cassette, wherein the transfer robot is moved by correcting the entry height into the cassette. The method of claim 3, wherein The control unit; When a plurality of wafers loaded at an angle among the wafers loaded in the cassette are continuous, when the wafers of the highest or lowest previous position among the loaded wafers are drawn out, the entry height into the cassette and the tilt A substrate transfer device, characterized in that for moving the transfer robot by position correction. In the substrate transfer method: Acquiring mapping information from a cassette on which a plurality of wafers are loaded, determining the position and inclination of at least one inclined wafer among the wafers loaded in the cassette from the mapping information, and then the position and the tilt And a wafer is taken out from the cassette by correcting the movement of the transfer robot corresponding to the degree of progress. The method of claim 5, Determining the degree of inclination; And determining the degree of inclination by calculating a time difference sensed from a plurality of sensors for acquiring the mapping information. The method according to claim 5 to 6, Determining the degree of inclination; And a substrate transfer method for determining that the transfer robot is inclined forward from the cassette. The method of claim 7, wherein Correcting the movement operation of the transfer robot; And one of the wafers loaded at an inclined position among the wafers loaded in the cassette, wherein the transfer robot is moved by correcting the entry height into the cassette. The method of claim 8, Correcting the movement operation of the transfer robot; When a plurality of wafers loaded at an angle among the wafers loaded in the cassette are continuous, when the wafers of the highest or lowest previous position among the loaded wafers are drawn out, the entry height into the cassette and the tilt A substrate transfer method, characterized in that for moving the transfer robot by position correction. The method of claim 9, Withdrawing the wafer from the cassette; And when the transfer robot picks up the wafer, moves the corrected movement of the transfer robot in reverse order.

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