KR20100060090A - Substrate transfer apparatus using linear scale and method for detecting position declination of the same - Google Patents

Abstract

PURPOSE: A substrate transfer apparatus using a linear scale and a method for detecting position declination of the same are provided to improve the accuracy of a transfer robot by detecting the position declination of the transfer robot through the z-scale of the linear scale. CONSTITUTION: A transfer robot(140) transfers a substrate. A driving unit(144) moves the transfer robot in horizontal. A transfer rail(146) is combined with the driving unit and the guides the driving unit. A linear scale is installed in the driving unit and the transfer rail and detects position data in the movement of the transfer robot. A controller controls the driving unit to obtain position data from the linear scale in the movement of the transfer robot. The controller detects position declination from the position data in the movement of the transfer robot.

Description

Substrate transfer device using linear scale and method for detecting position deviation thereof {SUBSTRATE TRANSFER APPARATUS USING LINEAR SCALE AND METHOD FOR DETECTING POSITION DECLINATION OF THE SAME}

Spinner equipment in semiconductor manufacturing equipment is a device for applying and developing photoresist on a substrate. Spinner installations include loading / unloading units, indexes, buffer units, process units and various transfer robots. The transfer robots include, for example, an index robot installed at an index, a main transport robot installed at a main transport path, and the like. The index robot transfers the substrate between the buffer unit and the loading / unloading unit, and the main transfer robot transfers the substrate between the buffer unit and the processing units. Process units, for example, have a coater, a development and a plurality of bake units to perform the application and development of the substrate. The buffer unit waits for substrates to be introduced into the processing units, or the substrates processed in the processing units are transferred to the loading / unloading unit.

The transfer robots such as the index robot and the main transfer robot have a plurality of transfer hands that each load one substrate, and the substrate is transferred in a state of being seated on the transfer hand. In order to prevent damage to the substrate during transfer, the transfer robots must accurately insert and withdraw each process unit. To this end, the transfer robots calculate the distance for each process unit spaced a certain distance from the home position, that is, the home position before the transfer, as coordinate values, and transfer the substrate to the corresponding process unit using each coordinate value. do.

In order to calculate the coordinate values of the respective process units corresponding to the respective home positions, the transfer robots detect and set the position of each process unit by using an encoder of a linear motor or by using a linear scale. do. The linear scale includes a home sensor that senses a home position, a lead tape in which data is displayed in the transfer direction, and a scale reader that scans data and reads coordinate values when the transfer robot is moved.

The method of using the encoder for coordinate detection and setting of the transfer robots is slower in response and less accurate than the method using the linear scale. In addition, the linear scale may have a case where foreign matters are attached to the lead tape or the scale reader, and thus, the accurate position cannot be detected.

In general, the linear scale uses coordinate values of phases A and B of the lead tape for position detection, position determination, and driving of the transfer robot. However, if the lead tape or scale reader is damaged by scratches, foreign matters, etc., the position data is acquired using the A phase and the B phase, and thus the position data and the wrong position data of the moved robot can be obtained. In addition, it is difficult to confirm whether the position data at this time is the exact position data of the actual position of the transfer robot. Therefore, after the transfer robot is moved to a specific position, an error may occur with a position where the actual transfer robot has moved the same distance as before. That is, the position data read by the scale reader should be the same as the position data of the transfer robot moved to a specific position, but the position of the transfer robot does not coincide with the position of the position data.

The occurrence of such an error prevents the movement of the substrate to the correct position between the substrate transfer apparatus and the process units, and therefore, it is impossible to accurately transfer the substrate to the process unit, resulting in damage to the substrate being transferred or a process accident.

An object of the present invention is to provide a substrate transfer device using a linear scale and a robot driving method thereof.

Another object of the present invention is to provide a substrate transfer device and a robot driving method thereof for detecting an error of position data using the Z phase of the linear scale.

It is still another object of the present invention to provide a substrate transfer apparatus and a robot driving method thereof for improving transfer accuracy using a linear scale.

In order to achieve the above objects, the substrate transfer apparatus of the present invention is characterized by controlling the precise driving of the transfer robot using a linear scale. In this way, the substrate transfer apparatus can match the position data with the position of the actual transfer robot.

A substrate transfer apparatus of the present invention according to this aspect includes a transfer robot for transferring a substrate; A driving unit for horizontally moving the transfer robot; A transfer rail coupled to the driving unit and guiding the driving unit; A linear scale installed on the driving unit and the transfer rail to detect position data when the transfer robot is transferred; And a control unit for controlling the driving unit to acquire the position data on the linear scale when the transfer robot moves, and detecting whether a position deviation occurs when the transfer robot moves from the position data.

In one embodiment, the control unit; The allowable range for the position deviation and reference data during normal operation of the transfer robot are set, and the position deviation is detected by comparing the current position data of the transfer robot and the reference data obtained from the linear scale. .

In another embodiment, the linear scale; A home sensor mounted at one end of the transfer rail and detecting a home position of the transfer robot and transmitted to the control unit; A lead tape attached to one side of the transfer rail by providing an origin position and providing coordinates of phases A, B, and Z disposed at different intervals from the origin; And a scale reader mounted on the driving unit to read the coordinates from the lead tape and transfer the coordinates to the controller when the transfer robot is moved along the transfer rail.

In another embodiment, the control unit; The reference data and the position data are set and stored as coordinate values of the A phase and the B phase with respect to the Z phase.

In another embodiment, the control unit; The position deviation is detected by comparing the reference data detected from the coordinates on Z in the normal operation of the transfer robot with the position data obtained from the coordinates on the Z on the current position when the transfer robot is moved.

In another embodiment, the control unit; When an error occurs as a result of the comparison between the reference data and the position data, it is determined whether the error is within the allowable range, and when the allowable range is exceeded, an alarm is generated.

According to another characteristic of this invention, the position deviation detection method of the board | substrate conveyance apparatus provided with the linear scale is provided. This method obtains and stores reference data for a specific position during normal movement of the substrate transfer device from the linear scale. At the same time, the substrate transfer apparatus sets an allowable range for the positional deviation generated during abnormal operation. Upon movement of the substrate transfer device, current position data of the substrate transfer device is obtained from the linear scale. Next, the reference data is compared with the current position data to detect whether a position deviation has occurred.

In one embodiment, the reference data and the current position data are provided as coordinate values of the A phase and the B phase for the specific position and the current position where the Z phase of the linear scale is detected during the normal operation of the transfer robot. .

In another embodiment, the method; If the position deviation exceeds the allowable range, further comprising generating an alarm.

As described above, the substrate transfer apparatus of the present invention sets and stores the reference data and the error tolerance range on the Z phase using a linear scale, and compares the detected position data on the Z phase with the reference data when the transfer robot moves. In this case, it is possible to detect whether a malfunction has occurred during movement.

In addition, the substrate transfer apparatus of the present invention detects the positional deviation by using the linear scale as the Z phase of the transfer robot, thereby compensating for the shortcomings of the conventional methods using the A and B phases. , Damage to the linear scale can be confirmed.

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 the configuration of a substrate processing apparatus according to the present invention.

Referring to FIG. 1, the substrate processing apparatus 100 of the present invention is a spinner apparatus for processing a photolithography process, and includes a loading / unloading unit 102, an index 106, and a buffer unit 108. And substrate processing units 120 and 130 including a plurality of processing units 122 to 126 and 132 to 136. In addition, the substrate processing apparatus 100 may include a substrate transfer part 150 disposed between the processing units 122 to 126 and 132 to 136.

The loading / unloading unit 102 includes a plurality of load ports. Each load port is mounted with a cassette 104 on which a plurality of wafers are mounted. The cassette 104 accommodates wafers processed in a processing unit or wafers to be inserted into the processing unit.

The index 106 is disposed between the loading / unloading unit 102 and the buffer unit 108, and the index robot 110 is installed. The index robot 110 transfers the wafer between the loading / unloading unit 102 and the buffer unit 108 while linearly moving along the transfer rail 118 installed at the bottom. The index robot 110 extracts at least one wafer from the cassette 104 seated on the loading / unloading unit 102 and loads the wafer into the buffer unit 108. In addition, the index robot 110 pulls out at least one wafer from the buffer unit 108 and loads it into the cassette 104 seated on the loading / unloading unit 102.

The index robot 110 includes a plurality of transfer arms 112 for loading wafers to be transferred, and an arm driver 114 and a driver 116 for driving the transfer arms 112, respectively. An arm driver 114 is installed below the transfer arms 112, and a driver 116 is connected to a lower part of the arm driver 114 by a drive shaft (not shown). The arm driver 114 horizontally moves the transfer arms 112 in the direction of the cassette 104 or the buffer unit 108, and each transfer arm 112 is individually driven by the arm driver 114. The transfer rail 118 is installed below the driving unit 116, and the index robot 110 is horizontally moved along the transfer rail 118. In addition, the driving unit 116 vertically moves and rotates the index robot 110 up and down.

The buffer unit 108 is installed at one side of the region where the index robot 110 is installed. The buffer unit 108 temporarily stores the wafers transferred by the index robot 110 and temporarily stores the wafers processed in the processing units 120 and 130.

The substrate transfer unit 150 transfers the wafer to the processing units or transfers the processed wafers from the processing units 122 to 126 and 132 to 136 to the buffer unit 108. The substrate transfer unit 150 is provided with a main transfer robot (MTR) 140 that is a substrate transfer device. The main transfer robot 140 is provided with a transfer rail 146 at the bottom. The main transfer robot 140 moves linearly along the transfer rail 146 between the buffer unit 108 and the process units 122-126, 132-136, and each process unit 122-126, 132-136. The wafers are transferred between each other. That is, the main transfer robot 140 pulls out at least one wafer from the buffer unit 108 and provides it to the processing units 122 to 126 and 132 to 136, and one processing unit 122 to 126 and 132 to 136. ) To provide the wafer to other processing units 122-126, 132-136. In addition, the main transfer robot 140 loads the wafer processed in the processing units 122 to 126 and 132 to 136 into the buffer unit 108.

The substrate processing units 120 and 130 include a plurality of processing units 122 to 126 and 132 to 136. The substrate processing units 120 and 130 perform a coating process of applying a photoresist such as a photoresist to a wafer and a developing process of removing photoresist in an exposed region or the opposite region from the wafer on which the exposure process is performed. Process units 122-126, 132-136 include, for example, an application unit, a developing unit, and a baking unit.

Referring to FIG. 2, the substrate processing units 120 to 130 have a structure in which the first processing unit 180a and the second processing unit 180b are stacked on each other. The first processing unit 180a is provided with coating units 130a for performing an application process on one side thereof, and baking units 120a are provided on the other side thereof. The second processing unit 180b is provided with developing units 130b for performing a developing process on one side thereof, and baking units 130b are provided on the other side thereof. Due to the above-described structure, the substrate processing apparatus 100 uses the wafer as the index unit 106, the first processing unit 180a, the interface unit (not shown), the exposure unit (not shown), the interface unit, and the second processing unit. 180b and the index portion 106 are sequentially moved.

In the first processing unit 180a, the first substrate transfer unit 150a is disposed at the center, and the second substrate transfer unit 150b is disposed at the center of the second processing unit 180b. The first and second transfer parts 150a and 150b are provided with the first and second moving paths 152a and 152b elongated in one direction, respectively.

The baking units 120a are arranged in one line along the first moving path 152a on one side of the first moving path 152a, and the coating units 130a are arranged on the other side of the first moving path 152a. It is arranged in a line along 152a. In addition, the baking units 120a and the application unit 130a are arranged to be stacked in a plurality of up and down. The first moving path 152a is provided with a first main transfer robot 140a for transferring wafers between the interface unit, the application unit 130a, the bake unit 120a, and the buffer units 108. A first transfer rail 146a is provided in the first movement path 152a so that the first main transfer robot 140a moves linearly in one direction.

In addition, the baking units 120b are arranged in one line along the second moving path 152b on one side of the second moving path 152b, and the developing units 130b are moved on the other side of the second moving path 152b. It is arranged in a line along the furnace 152b. In addition, the baking units 120b and the developing unit 130b are arranged so that a plurality of baking units 120b are stacked up and down. The second moving path 152b is provided with a second main transfer robot 140b for transferring wafers between the interface unit, the developing unit 130b, the bake unit 120b, and the buffer units 108. A second transfer rail 146b is provided in the second movement path 152b so that the second main transfer robot 140b moves linearly in one direction.

Specifically, referring to FIGS. 1 and 3, the main transfer robots 140: 140a and 140b may include a hand drive unit 141, a plurality of transfer hands 142, a drive shaft 143, a vertical and rotation drive unit 148, and a horizontal plane. The drive unit 144 is included. The horizontal drive unit 144 is installed on the transfer rail 146 to move linearly along the transfer rail 146.

The hand driver 141 horizontally moves the transfer hands 142, respectively, and each transfer hand 142 is individually driven by the hand driver 141. The transfer hands 142 are installed on the upper portion of the hand driver 141. The transfer hands 142 may be disposed to face each other in the vertical direction and may load one wafer each. Some of the transfer hands 142 withdraw the wafer from the buffer unit 108 and provide it to the baking unit in an idle state. In addition, the rest of the transfer hands 142 withdraw the wafer from the completed process unit and loads the wafer in the buffer unit 108.

Meanwhile, the driving shaft 143 is connected to the lower end of the hand driver 141. The drive shaft 143 has an upper portion coupled with the hand driver 141 and a lower portion coupled with the vertical and rotation drivers 148. The drive shaft 143 vertically moves and rotates up and down by the vertical and rotation drivers 148 to vertically move and rotate the hand driver 141. Accordingly, the transfer hands 142 move and rotate up and down together. The horizontal driver 144 is coupled to the transfer rail 146 to move horizontally along the transfer rail 146.

And the linear scale 160 is installed in the conveyance rail 146 and the horizontal drive unit 144. The linear scale 160 includes a home sensor 162 installed at one end of the transfer rail 146, a lead tape 164 attached to one side of the transfer rail 146, and a transfer. A scale reader (166 of FIG. 4) is read along the rail 146 to read the coordinates provided to the lead tape 164.

The home sensor 162 is attached to the home position of the main transfer robot 140 to detect the home position. The lead tape 164 displays a plurality of types of coordinates 164a and 164b having different intervals with respect to the origin 164c. Here, origin 164c coincides with the home position. These coordinates 164a and 164b are read by the scale reader 166 while the main transport robot is in motion. That is, the data provided from the scale reader 166 is the same as the position detection signal of a general motor encoder. The data includes position coordinates of phase A, phase B, Z phases 164a and 164b and origin 164c. The Z phase 164a is a pulse value of the position detection signal detected at one rotation of the motor.

The lead tape 164 is provided at the lower end with coordinates 164b for detecting a plurality of A and B phases when the main transport robot 140 moves in correspondence with the origin 164c. In addition, the lead tape 164 is provided with coordinate marks 164a (referance marks) for detecting a plurality of Z phases with respect to the position of the horizontal moving part 144 at the upper end thereof. The Z phases 164a are disposed at regular intervals on the upper end of the lead tape 164. In addition, a plurality of A and B phases 164b are disposed at lower intervals between the Z phases 164a.

The main transfer robot 140 moves horizontally along the transfer rail 146 by driving the horizontal driver 144. The main transport robot 140 is located in a specific section while moving in the opposite direction from the origin 164c. Scale reader 166 reads coordinates 164a and 164b of lead tape 164 attached to transfer rail 146. The coordinates 164a, 164b, 164c of the linear scale 160 are provided to determine the position for each process unit 122-126, 132-136 of the main transfer robot 140. At this time, in order to detect whether the position of the moved main transport robot 140 is correct, the Z phase of the linear scale 160 is used in the present invention.

In detail, an operation of detecting an error with respect to the position of the main transfer robot 140 using the linear scale 160 will be described with reference to FIGS. 4 and 5.

4 and 5, the substrate processing apparatus 100 uses the linear scale 160 and the linear scale to accurately feed and unload the main transfer robot 140 into each of the processing units 120 to 130. And a controller 170 for controlling the main transfer robot 140 using the data measured from the 160. The controller 170 includes, for example, a motion controller and a driver. The control unit 170 uses the home position of the main transfer robot 140 detected by the home sensor 162 and the origin position 164c of the lead tape 164 using data provided from the scale reader 166. Detect. In addition, the controller 170 controls the position to be moved to each process unit (122 ~ 126, 132 ~ 136) to the value of the phase A and phase B (164b) when the main transport robot is driven. However, due to contamination or damage of the linear scale, the values of the phase A and phase B 164b may not coincide with the position data of the main transfer robot 140 actually moved.

In order to solve this problem, the controller 170 first detects and stores coordinate values of the A phase and the B phase of the position where the Z phase is detected. At this time, the stored coordinate value is used as reference position data detected from the Z phase in the normal operation of the main transport robot 140. In addition, the controller 17 sets and stores an allowable range for this error when a position deviation occurs. The control unit 170 receives a specific command from the control unit 170 when the main transport robot 140 is moved, for example, when the main transport robot 140 moves to an origin position (ORIGIN), or during a process. When moved, the coordinate value on the Z of the current position of the main transport robot 140 is obtained and compared with the reference position data to determine whether an error occurs. If an error occurs and the generated error is within the allowable range, the controller 170 determines that the movement is normal. However, if the error exceeds the allowable range, an alarm is generated to check whether an abnormality occurs in the main transfer robot 140, the horizontal drive unit 144, or the linear scale 160.

Therefore, the substrate transfer device 140 of the present invention sets and stores the reference data and the error range for the Z phase, and when the main transfer robot 140 moves, by comparing the detected position data on the Z phase with the reference data, a malfunction occurs during the movement. Can be detected.

6 is a flowchart showing a driving procedure for detecting a positional deviation in order to detect a malfunction occurring during the movement of the substrate transfer apparatus of the present invention.

Referring to FIG. 6, in step S200, the main transfer robot 140 moves from the home sensor 162, that is, from the home position along the transfer rail 146 to which the lead tape 164 is attached, in the opposite direction.

In step S202, it is determined whether the Z phase is detected during the movement. If the Z phase is not detected, the main transfer robot 140 continues to move.

In step S204, coordinate data read from phase A and phase B of the position where the Z phase is detected is stored. This data is used as reference data.

In step S206, the main transport robot 140 is moved during the process. For example, the main transfer robot 140 moves in response to an operation ORIGIN to the origin position or receives a specific command from the controller 170. At this time, the Z phase is detected again in a specific section during the movement of the main transport robot 140 in step S208. That is, if the Z phase is detected, the flow advances to step S210 to obtain current position data of the detected Z phase.

In step S212, the reference data is compared with the current position data. As a result of the comparison, if an error occurs, it is determined whether the error generated in step S214 is within an allowable range. Here, the allowable range error is preset in the controller 170.

In other words, if the error is within the allowable range, the process proceeds to step S216, otherwise an alarm is generated in step S218. If the error is larger than the allowable range error, the state of the linear scale 160 or the horizontal drive unit 144 is checked. In this case, scratches may occur on the scale reader 166 reading the A phase and the B phase, or foreign matter may be attached to the lead tape 164. As a result, after the main transport robot 140 is driven, the actual position of the main transport robot 140 may be different from the previously set position. Therefore, the substrate transfer apparatus of the present invention detects the positional deviation by using the Z phase, thereby compensating for the disadvantages of the conventional method using the A phase and the B phase, and a malfunction or linear scale generated when the main transfer robot 140 moves. 160 may be damaged or the like.

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 is a diagram showing a configuration of a substrate processing apparatus according to the present invention;

FIG. 2 is a perspective view showing the configuration of the substrate processing apparatus shown in FIG. 1; FIG.

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

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

FIG. 5 is a diagram illustrating a configuration of a linear scale of the substrate transfer apparatus shown in FIG. 3; FIG. And

6 is a flowchart showing a driving procedure for detecting a positional deviation generated during movement using the linear scale of the substrate transfer apparatus according to the present invention.

Explanation of symbols on the main parts of the drawings

100: substrate processing apparatus 120, 130: substrate processing unit

140: main transport robot 144: horizontal drive unit

146 transfer rail 150 substrate transfer portion

160: linear scale 162: home sensor

164: lead tape 166: scale reader

170: control unit

Claims (9)

In the substrate transfer device: A transfer robot for transferring a substrate; A driving unit for horizontally moving the transfer robot; A transfer rail coupled to the driving unit and guiding the driving unit; A linear scale installed on the driving unit and the transfer rail to detect position data when the transfer robot is transferred; And a controller for controlling the driving unit to acquire the position data on the linear scale when the transfer robot moves, and detecting whether a position deviation occurs when the transfer robot moves from the position data. Board | substrate conveying apparatus made into. The method of claim 1, The control unit; Setting the allowable range for the position deviation and reference data in the normal operation of the transfer robot, and comparing the current position data of the transfer robot obtained from the linear scale with the reference data to detect the position deviation. Substrate transfer apparatus, characterized in that. The method according to claim 1 or 2, The linear scale; A home sensor mounted at one end of the transfer rail and detecting a home position of the transfer robot and transmitted to the control unit; A lead tape attached to one side of the transfer rail by providing an origin position and providing coordinates of phases A, B, and Z disposed at different intervals from the origin; And a scale reader mounted on the driving unit to read the coordinates from the lead tape and transfer the coordinates to the controller when the transfer robot is moved along the transfer rail. The method of claim 3, wherein The control unit; And storing and setting the reference data and the position data as coordinate values of the A phase and the B phase with respect to the Z phase. The method of claim 4, wherein The control unit; The positional deviation is detected by comparing the reference data detected from the coordinates on Z in the normal operation of the transfer robot with the position data obtained from the coordinates on the Z on the current position when the transfer robot is moved. Substrate conveying apparatus made into. The method of claim 5, The control unit; And if an error occurs as a result of the comparison between the reference data and the position data, determining whether the error is within the allowable range, and generating an alarm if the error exceeds the allowable range. In the position deviation detection method of the substrate transfer apparatus provided with the linear scale: Obtaining and storing reference data for a specific position during normal movement of the substrate transfer apparatus from the linear scale, setting an allowable range for position deviation generated when the substrate transfer apparatus is abnormally operated, and transmitting the substrate transfer apparatus. At the time of movement, the current position data of the substrate transfer apparatus is obtained from the linear scale, and then the position deviation of the substrate transfer apparatus is detected by comparing the reference data and the current position data to detect whether a position deviation has occurred. Detection method. The method of claim 7, wherein The reference data and the current position data, the substrate transfer, characterized in that provided in the coordinates of the phase A and B for the specific position and the current position where the Z phase of the linear scale is detected during normal operation of the transfer robot, respectively. Method for detecting position deviation of the device. 9. The method according to claim 7 or 8, The method; And generating an alarm if the position deviation exceeds the allowable range.

Images