JP2020205299A - Wafer transfer system - Google Patents

Abstract

To provide a wafer transfer system capable of preventing foreign matter from adhering to a wafer during transporting the wafer.SOLUTION: A wafer transfer system 10 includes: a robot (conveyance mechanism) 20 that conveys wafer 1; a clean chamber 30; and a fan (first blower mechanism) 40 that forms an airflow from the ceiling 31 to the bottom 32 of the clean chamber 30. The robot 20 includes: a hand unit 22 that holds a wafer 1; a fan (second blower mechanism) 70 that, when the hand unit 22 holds the wafer 1, forms an airflow from the bottom surface 1b side of the wafer 1 to the bottom 32 of the clean chamber 30; and a control unit that controls the drive state of the fan 70 depending on the presence or absence of the wafer 1 held by the hand unit 22.SELECTED DRAWING: Figure 3

Description

The present invention relates to a wafer transfer device, and more particularly to a wafer transfer device in which a transfer mechanism unit for transferring a wafer is housed in a locally cleaned clean chamber.

Japanese Unexamined Patent Publication No. 2009-200160 (Patent Document 1) describes a configuration in which a traveling device of a transport robot that moves in the transport device is provided on a side wall portion. According to Patent Document 1, it is described that by providing the traveling device on the side wall portion, it is possible to eliminate obstacles for the downflow from the fan filter unit installed on the upper part of the device to the exhaust port. Further, Japanese Patent Application Laid-Open No. 2010-3867 (Patent Document 2) conveys an opening adjustment function for adjusting the opening ratio of an air discharge opening provided on the floor surface of a housing having a clean space in which a transfer robot can be accommodated. Local clean room for use is listed.

Japanese Unexamined Patent Publication No. 2009-200160 JP-A-2010-3867

The wafer transfer device includes a clean chamber that locally cleans the space where the wafer transfer operation is performed. The clean room continuously supplies clean gas from the ceiling to form an air flow (called a downflow) from the ceiling to the bottom. Therefore, a fan filter unit in which a fan and a filter are integrated is arranged on the ceiling of the clean room, and gas is supplied to the clean room via the fan filter unit.

However, according to the study of the inventor of the present application, when the wafer is conveyed in the clean chamber, the downflow is blocked by the wafer. As a result, it was found that there is a concern that a region where gas stays is formed directly under the lower surface of the wafer. If there is a space in the clean chamber where gas stays, there is a concern that the particles accumulated in the space will be rolled up and adhere to the wafer as foreign matter. Further, when a blower mechanism for eliminating the retention of gas on the lower surface side of the wafer is provided, it is necessary to consider the influence of the blower mechanism on the airflow of the entire clean room.

A brief description of typical forms of the inventions disclosed in the present application is as follows.

That is, the wafer transfer device according to the embodiment of the present invention includes a transfer mechanism unit for transporting a wafer having a first main surface and a second main surface opposite to the first main surface, a ceiling portion, and the above. It has a clean chamber having a bottom portion facing the ceiling portion, and a first ventilation mechanism portion attached to the ceiling portion and forming an air flow from the ceiling portion side to the bottom portion side of the clean chamber. The transport mechanism portion includes a hand portion that holds the wafer with the first main surface of the wafer facing the ceiling portion, and a first arm portion that supports the hand portion and operates the hand portion. A second support portion that supports the first arm portion and a second hand portion that forms an air flow from the second main surface side of the wafer toward the bottom portion of the clean chamber when the hand portion holds the wafer. It includes a blower mechanism unit and a control unit that controls a driving state of the second blower mechanism unit according to whether or not the wafer is held by the hand unit.

Among the inventions disclosed in the present application, the effects obtained by typical ones will be briefly described as follows.

That is, when the wafer is conveyed, it is possible to prevent foreign matter from adhering to the wafer.

Issues, configurations and effects other than those described above will be clarified by the description of the following embodiments.

It is a perspective plan view which shows the structural example of the wafer transfer apparatus which is one Embodiment. It is sectional drawing which follows the AA line of FIG. It is an enlarged cross-sectional view along the line BB of FIG. It is an enlarged plan view of the robot shown in FIG. It is a flow chart which shows an example of the control of the driving state of a plurality of fans by the control part shown in FIG. It is a top view which shows the modification of the transport mechanism part shown in FIG. It is a modification with respect to FIG. 3, and is sectional drawing of the wafer transfer apparatus which has the transfer mechanism part shown in FIG. It is a top view which shows the other modification of the transport mechanism part shown in FIG. It is another modification with respect to FIG. 3, and is sectional drawing of the wafer transfer apparatus which has the transfer mechanism part shown in FIG. It is a flow chart which shows the modification of the control of the driving state of a plurality of fans by the control part shown in FIG.

In each of the drawings for explaining the following embodiments, the same members are designated by the same reference numerals in principle, and the repeated description thereof will be omitted. In addition, in order to make the drawing easy to understand, hatching may be added even if it is a plan view.

<Overview of wafer transfer equipment>
FIG. 1 is a perspective plan view showing a configuration example of the wafer transfer device of the present embodiment. FIG. 2 is a cross-sectional view taken along the line AA of FIG. FIG. 3 is an enlarged cross-sectional view taken along the line BB of FIG. FIG. 4 is an enlarged plan view of the robot shown in FIG. FIG. 1 shows the internal structure of the clean chamber 30 with the fan 40 and the filter 50 shown in FIGS. 2 and 3 removed. In FIG. 1, the moving direction and the rotational movement direction of the robot 20 are schematically shown by using thick arrows. In FIGS. 2 and 3, the direction of the air flow in the clean room 30 is schematically shown by the arrow of the alternate long and short dash line. In FIG. 4, the operation of the hand portion 22 included in the robot 20 is shown by using arrows and alternate long and short dash lines.

The wafer transfer device 10 of the present embodiment shown in FIG. 1 has a robot (transfer mechanism unit) 20 as a transfer mechanism unit for transporting the wafer (board) 1 and a clean room 30 in which the robot 20 is housed. .. As shown in FIG. 2, the clean room 30 includes a ceiling portion 31, a bottom portion 32 facing the ceiling portion 31, and a side wall portion 33 located between the ceiling portion 31 and the bottom portion 32 and surrounding the robot 20. .. Further, the wafer transfer device 10 is arranged on the ceiling portion 31, and has a fan (first blower mechanism portion) 40 (see FIG. 2) that forms an air flow from the ceiling portion 31 side to the bottom portion 32 side of the clean chamber 30. Have. The fan 40 shown in FIG. 2 supplies gas from the outside to the inside of the clean chamber 30 through a filter 50 that filters particles contained in the gas. Further, as shown in FIG. 1, the wafer transfer device 10 has an alignment unit (alignment mechanism unit) 60 and a control unit 71 arranged in the clean chamber 30.

Various manufacturing processes of semiconductor devices include a step of forming an integrated circuit including a semiconductor element on a wafer 1 as a semiconductor substrate, an inspection of the formed integrated circuit, and an inspection of the wafer 1 itself as a semiconductor substrate. Steps are included. Further, since the integrated circuit is formed as a fine circuit pattern by using, for example, photolithography technology, the step of forming the integrated circuit includes a large number of steps. Further, when foreign matter adheres to the wafer 1, even particles such as dust having a fine size may cause a defect in the circuit pattern. When a defect in the circuit pattern is found by inspection, the distribution of the defective product can be prevented by not using the portion as a product, but the number of semiconductor devices that can be obtained from one wafer 1 is reduced. As a result, the manufacturing efficiency of the semiconductor device is lowered. In the following description, the adhesion of foreign matter to the wafer 1 may be described as "contamination".

Therefore, in order to prevent foreign matter from adhering to the wafer 1, a clean environment in which the number of particles contained in the atmosphere is controlled to be reduced is required at the place where the wafer 1 is handled. To. However, since various manufacturing devices are used in the manufacturing process of semiconductor devices, it is difficult to create a high-level clean environment in the atmosphere of the entire manufacturing line including a large number of manufacturing devices. Therefore, it is effective to provide a locally cleaned clean chamber 30 and handle the wafer 1 in the clean chamber 30 as in the wafer transfer device 10 of the present embodiment. A device that locally cleans the space in which the wafer 1 is conveyed by the robot 20 as a transfer mechanism unit is called a mini-environment device.

In the method of manufacturing a semiconductor device using a mini-environment device, the wafer 1 is conveyed between the manufacturing devices in a state of being housed in a containment vessel 2 called a FOUP (Front Opening Unified Pod). The containment vessel 2 is a container capable of accommodating a plurality of wafers 1. The robot 20 included in the wafer transfer device 10 takes out the wafers 1 one by one from the containment vessel 2 and conveys the taken out wafers 1 to the processing chamber 3. The processing chamber 3 is a clean space apart from the wafer transfer device 10, and a processing device 4 such as an inspection device is arranged inside.

Further, in the example shown in FIG. 1, the wafer 1 is subjected to an alignment step in the alignment unit 60 arranged in the clean chamber 30 after being taken out from the containment vessel 2 and before being transported to the processing chamber 3. Will be done. The alignment step is a step of aligning the wafer 1, and adjusts the orientation of the wafer 1 based on a mark (not shown) such as an oriental flat or a notch provided on the wafer 1. By performing the alignment step, when the wafer 1 is processed such as processing or inspection in the processing chamber 3, the processing can be performed at a predetermined position of the wafer 1.

In the present embodiment, the wafer transfer device 10 does not include the containment vessel 2 and the processing chamber 3. In the side wall portion 33 of the clean chamber 30, openings 34 and 35 (see FIG. 3) are formed in which the wafer 1 is transferred between the containment vessel 2 and the robot 20 or between the processing chamber 3 and the robot 20. Has been done. Although not shown, the opening 34 is provided with a door such as a shutter that can be opened and closed.

In the XY planes orthogonal to each other shown in FIG. 1, the robot 20 can move along a traveling axis 21 extending in the X direction. In FIG. 1, the movable direction of the robot 20 is indicated by a thick arrow as the direction 20D1. Further, as shown in the rotation direction 20D2 in FIG. 1, the robot 20 can rotate along the XY plane on the traveling shaft 21.

Further, as shown in FIG. 4, the robot 20 has a hand portion 22 that holds the wafer 1 (see FIG. 1), an arm portion 23 that is connected to the hand portion 22 and expands and contracts the hand portion 22, and an arm portion 23. A support portion (stage) 25 for supporting the above is provided. In the example shown in FIG. 4, the arm portion 23 is mounted on a turntable 24 rotatably configured in the rotation direction 20D2 (see FIG. 1) and is supported by the support portion 25 via the turntable 24. The arm portion 23 includes a plurality of plate-shaped members 23m and a plurality of joint portions 23j for rotatably connecting the plurality of plate-shaped members 23m. By changing the angles of the plurality of plate-shaped members 23m with the joint portion 23j as the rotation axis, the arm portion 23 can expand and contract the hand portion 22 connected to the arm portion 23 along the direction 22D1. In the example shown in FIG. 4, the direction 22D1 coincides with the Y direction. However, if the turntable 24 rotates, the direction 22D1 may coincide with an arbitrary direction intersecting the Y direction in the XY plane.

As shown in FIG. 1, the wafer transfer device 10 has a plurality of fans 70 attached to the robot 20 and a control unit 71 that controls the driving state of the fans. The fan 70 and the control unit 71 will be described later.

<Overview of wafer transfer operation>
The wafer transfer device 10 of the present embodiment shown in FIGS. 1 to 3 transfers the wafer 1 via the robot 20 as follows. First, 2 is connected to the wafer transfer device 10 for storage. FIG. 1 shows a state in which three containment vessels 2 are connected to the wafer transfer device 10, but the number of connections of the containment vessels 2 is not limited to three, and there are various modifications. A plurality of wafers 1 are housed in each of the containment vessels 2. The inside of each of the containment vessels 2 is maintained in a clean state, and the wafer 1 can be prevented from being contaminated inside the containment vessel 2. The containment vessel 2 includes a door that can be opened and closed as needed. As shown in FIG. 3, the containment vessel 2 is connected to a position communicating with the inside of the clean chamber 30 via an opening 34 provided in the side wall portion 33.

Wafers 1 are taken out one by one from the containment vessel 2. The robot 20 expands and contracts the hand portion 22 after the tip of the hand portion 22 moves to a position facing the containment vessel 2. When the hand portion 22 extends along the direction 22D1 (see FIG. 4), the tip of the hand portion 22 extends into the containment vessel 2 and sucks and holds one wafer 1. After sucking the wafer 1, the hand unit 22 operates so as to shrink toward the turntable 24 (see FIG. 4) while holding the wafer 1. After that, the robot 20 moves toward the alignment unit 60 while holding the wafer 1.

The robot 20 rotates in front of the alignment unit 60 along the rotation direction 20D2 shown in FIG. 1, and after the tip of the hand portion 22 (see FIG. 4) rotates in a direction facing the alignment unit 60, the robot 20 rotates. To stop. After that, the robot 20 expands and contracts the hand portion 22. At this time, the direction 22D1 (see FIG. 4), which is the expansion / contraction direction of the hand portion 22, is along the X direction shown in FIG. Therefore, the tip of the hand portion 22 extends upward of the alignment unit 60 while holding the wafer 1. The holding of the wafer 1 by the hand portion 22 is released on the alignment unit 60, and the wafer 1 is arranged on the alignment unit 60. On the alignment unit 60, as described above, the orientation of the wafer 1 is adjusted based on a mark (not shown) such as an oriental flat or a notch provided on the wafer 1. The oriented wafer 1 is held again by the hand portion 22 of the robot 20. When the alignment step is completed, the robot 20 holds the wafer 1 after the alignment step again via the hand unit 22.

Next, the robot 20 rotates in front of the alignment unit 60 along the rotation direction 20D2 shown in FIG. 1, and after the tip of the hand portion 22 (see FIG. 4) rotates in a direction facing the processing chamber 3. , Stop the rotation operation. After that, the robot 20 moves along the direction 20D1 to a position where the opening 35 (see FIG. 3) and the tip of the hand portion 22 face each other. The opening 35 is a continuous passage for passing the wafer 1 to the processing chamber 3. At the position where the opening 35 and the tip of the hand portion 22 face each other, the robot 20 expands and contracts the hand portion 22. At this time, the direction 22D1 (see FIG. 4), which is the expansion / contraction direction of the hand portion 22, is along the Y direction shown in FIG. Therefore, the tip of the hand portion 22 extends toward the opening 35 while holding the wafer 1. On the processing device 4 arranged in the processing chamber 3, the holding of the wafer 1 by the hand unit 22 is released, and the wafer 1 is arranged on the processing device 4. In the processing device 4, a processing process such as an inspection process is performed. When the processing by the processing apparatus 4 is completed, the robot 20 holds the wafer 1 after the processing step again via the hand unit 22.

Next, the robot 20 rotates in front of the opening 35 along the rotation direction 20D2 shown in FIG. 1, and the tip of the hand portion 22 (see FIG. 4) is connected to the side wall portion 33 to which the containment vessel 2 is connected. After rotating to the opposite direction, the rotation operation is stopped. After that, the robot 20 moves along the direction 20D1 to a position where the opening 34 (see FIG. 3) and the tip of the hand portion 22 face each other. At a position where the opening 34 and the tip of the hand portion 22 face each other, the robot 20 expands and contracts the hand portion 22. At this time, the direction 22D1 (see FIG. 4), which is the expansion / contraction direction of the hand portion 22, is along the Y direction shown in FIG. Therefore, the tip of the hand portion 22 extends toward the containment vessel 2 via the opening 34 while holding the wafer 1. In the containment vessel 2, the holding of the wafer 1 by the hand portion 22 is released, and the wafer 1 is arranged in the containment vessel 2.

After repeating the above operation and inspecting each of the plurality of wafers 1 housed in the containment vessel 2, the door of the containment vessel 2 is closed. Further, the opening 34 (see FIG. 3) is closed by a shutter or the like (not shown). After that, the containment vessel 2 is transported to the next processing step. On the other hand, the wafer transfer device 10 performs the same operation as described above for the plurality of wafers 1 housed in another containment vessel 2. As described above, in the case of the wafer transfer device 10, the steps of taking out the wafer 1 from the containment vessel 2 and transporting the wafer 1 to the processing chamber 3 and the process of receiving the processed wafer 1 and transporting the wafer 1 to the containment vessel 2 are automated. ing. Therefore, the factors that cause foreign matter to be generated in the clean chamber 30 where the wafer 1 is exposed are reduced.

<Airflow in a clean room>
In the wafer transfer device 10 of the present embodiment described above, by keeping the environment in the clean chamber 30 in a highly clean environment, the period until the wafer 1 is taken out from the containment vessel 2 and delivered to the processing chamber 3 ( It is possible to prevent foreign matter from adhering to the wafer 1 during the period (first wafer transfer period) and the period until the wafer is taken out from the processing chamber and delivered to the containment vessel 2 (second wafer transfer period). Further, by reducing the number of operations performed during the first and second wafer transfer periods, the volume of the space required for a highly clean environment can be reduced. If the volume of the space required for a clean environment is reduced, the equipment (fans and filters) required for cleaning can be simplified.

As a method of keeping the environment in the clean chamber 30 in a highly clean environment, there is a method of forming an air flow (called downflow) in which a clean gas flows from the ceiling portion 31 to the bottom portion 32 of the clean chamber 30. As schematically shown by the two-dot chain line arrow in FIGS. 2 and 3, the wafer transfer device 10 of the present embodiment also forms a downflow from the ceiling portion 31 to the bottom portion 32. Specifically, the ceiling portion 31 of the clean chamber 30 is provided with an opening 31H, a fan 40, and a filter 50. The fan 40 takes in external gas from the opening 31H into the clean chamber 30 through the filter 50. .. In the filter 50, the particles contained in the gas are trapped, and the purified gas is supplied into the clean chamber 30. The bottom portion 32 is provided with a plurality of openings 32H for discharging the gas sent from the ceiling portion 31 to the outside of the clean chamber 30. In the examples shown in FIGS. 2 and 3, the bottom portion 32 has a grating (lattice-like floor), and a large number of openings 32H are formed. In the case of the wafer transfer device 10, the gas (for example, air) outside the clean chamber 30 is supplied into the clean chamber 30 via the fan 40 and the filter 50, and is provided on the bottom 32 as a downflow toward the bottom 32. It is discharged to the outside through the opening 32H.

The wafer 1 includes an upper surface (first main surface) 1t and a lower surface (second main surface) 1b opposite to the upper surface 1t. The wafer 1 is held by the hand portion 22 of the robot 20 with the entire upper surface 1t facing the ceiling portion 31. Therefore, the downflow supplied from the ceiling portion 31 by the above method is sprayed toward the structure in the clean chamber 30 including the upper surface 1t of the wafer 1. Therefore, if particles such as dust are generated in the clean room 30 due to the operation of the robot 20, for example, the particles are conveyed to the downflow and are prevented from adhering to the upper surface 1t side of the wafer 1. it can.

Since the hand portion 22 of the robot 20 of the present embodiment has a structure of sucking and holding the lower surface 1b side of the wafer 1, the entire upper surface 1t of the wafer 1 faces the ceiling portion 31. However, as a modification of the hand portion 22, there is also a type of hand portion that sandwiches (sandwiches) the side surface of the wafer 1. In this case, the peripheral edge portion of the upper surface 1t of the wafer 1 may be covered with a member for holding the hand portion (for example, a resin cushioning material). However, even in this case, the portion where the other member is interposed between the ceiling portion 31 and the wafer 1 is only a part of the peripheral portion, and the region forming the semiconductor integrated circuit faces the ceiling portion 31. It can be considered that substantially the entire upper surface 1t of the wafer 1 faces the ceiling portion 31.

<Airflow in the space directly under the wafer>
As described above, by continuously applying the downflow from the ceiling portion 31 to the upper surface 1t of the wafer 1, it is possible to prevent foreign matter from adhering to the upper surface 1t of the wafer 1. However, when the wafer 1 is conveyed in the clean chamber 30, the downflow is blocked by the wafer 1. As a result, it was found that there is a concern that a region where gas stays is formed directly under the lower surface 1b of the wafer 1.

Therefore, in the case of the present embodiment, as shown in FIG. 3, when the hand portion 22 holds the wafer, the second blower that forms an air flow from the lower surface 1b side of the wafer 1 toward the bottom 32 of the clean chamber 30. A plurality of fans 70 are provided as a mechanical unit. As shown in FIG. 4, each of the plurality of fans is attached to the support portion 25. When the fan 70A located at a position overlapping the wafer 1 is operated while the wafer 1 is held by the hand portion 22, the gas in the space immediately below the wafer 1 is sucked into the fan 70A and discharged toward the bottom 32. To. As a result, a downflow can be formed directly under the wafer 1.

However, when providing a ventilation mechanism for eliminating the retention of gas on the lower surface 1b side of the wafer 1, it is necessary to consider the influence of the ventilation mechanism on the air flow of the entire clean chamber 30. For example, in the example shown in FIG. 3, when the wafer 1 is held, a downflow can be formed directly under the wafer 1 by rotating the fan 70A arranged at a position overlapping the wafer 1. On the other hand, for example, the timing before the wafer 1 is taken out from the storage container 2, that is, the same drive as when the plurality of fans 70 hold the wafer 1 when the hand portion 22 of the robot 20 does not hold the wafer 1. When rotating in a state (which can be rephrased as a rotation speed or an air flow rate per unit time), there is a concern that the airflow becomes faster than necessary around the plurality of fans 70 and particles are rolled up.

Therefore, the transfer mechanism unit of the wafer transfer device 10 of the present embodiment controls the driving state of a plurality of fans 70 as the second blower mechanism unit depending on whether or not the hand unit 22 of the robot 20 holds the wafer 1. The control unit 71 (see FIG. 1) is provided. FIG. 5 is a flow chart showing an example of control of a driving state of a plurality of fans by the control unit shown in FIG.

As shown in FIG. 3, the transfer mechanism unit of the wafer transfer device 10 includes a sensor 72 that detects whether or not the wafer 1 is held. The type and mounting position of the sensor are not particularly limited as long as the presence or absence of holding of the wafer 1 can be detected, and for example, a method of mounting the infrared sensor below the hand portion 22 can be exemplified. In the case of the present embodiment, the sensor 72 (see FIG. 3) is mounted on each of the plurality of fans 70 shown in FIG.

As shown in FIG. 5, the detection signal SG1 or SG2 output from the sensor 72 is transmitted to the control unit 71 shown in FIG. The control unit 71 receives, for example, the detection signals SG1 and SG2 output from the sensor 72 and performs data processing based on these, and the drive signal DR1 for driving the fan 70 based on the data processing result. It is a computer including an arithmetic processing circuit that generates DR2. The control unit 71 outputs a drive signal DR1 or DR2 to each of the plurality of fans 70 based on the detection signals SG1 or SG2 output from each of the plurality of sensors 72. For example, as in the example shown in FIGS. 1 and 3, when the wafer 1 is held at a position overlapping the fan 70A among the plurality of fans 70, the sensor 72A means that the wafer 1 is held. The detection signal SG1 is output. Further, since the fans 70B and 70C do not overlap with the wafer 1, the sensors 72B (see FIG. 5) and 72C (see FIG. 5) output a detection signal SG2 meaning that the wafer 1 is not held.

Based on the detection signal SG1 from the sensor 72A, the control unit 71 outputs a drive signal DR1 that rotates at the first rotation speed to the fan 70A arranged at a position overlapping the wafer 1 among the plurality of fans 70. To do. The first rotation speed is such that a downflow can be formed directly under the wafer 1 shown in FIG. 3, and is faster than the second rotation speed described later. Further, the control unit 71 has a second rotation speed for each of the fans 70B and 70C arranged at positions that do not overlap with the wafer 1 among the plurality of fans 70, based on the detection signals SG2 from the sensors 72B and 72C. A rotating drive signal DR2 is output. The second rotation speed is slower than the first rotation speed.

When the robot 20 is moving along the direction 20D1 shown in FIG. 1, the wafer 1 is continuously arranged at a position overlapping the fan 70A. Since each of the plurality of sensors 72 (see FIG. 5) continuously detects the presence or absence of the wafer 1, the fan 70A continues to rotate at the first rotation speed, and the fans 70B and 70C continue to rotate at the second rotation speed. Continues to rotate (or stays stopped).

Further, when the robot 20 rotates along the rotation direction 20D2 in the vicinity of the alignment unit 60, the wafer 1 does not overlap with the fan 70A and moves to a position where it overlaps with the fan 70B. At this time, the detection signal SG1 is output from the sensor 72B shown in FIG. 5, and the detection signal SG2 is output from the sensors 72A and 72C. The control unit 71 outputs a drive signal DR1 to the fan 70B so as to rotate at the first rotation speed based on the detection signal SG1. Further, the control unit 71 outputs a drive signal DR2 so as to rotate (or stop the rotation) at the second rotation speed with respect to the fans 70A and 70C based on the detection signal SG2.

Further, when the wafer 1 is arranged on the alignment unit 60, the robot 20 is in a state of not holding the wafer 1. At this time, the detection signal SG2 is output from each of the sensors 72A, 72B, and 72C shown in FIG. Based on the detection signal SG2, the control unit 71 outputs a drive signal DR2 so as to rotate (or stop the rotation) at the second rotation speed for each of the fans 70A, 70B, and 70C. In this way, when the robot 20 does not hold the wafer 1, the air blown by the plurality of fans 70 is suppressed, so that the airflow becomes faster than necessary around the plurality of fans 70 and the particles are wound up. Can be prevented.

After that, similarly, according to the operation of the robot 20 (see FIG. 1), the control unit 71 outputs the drive signal DR1 to the fan 70 at the position where it overlaps with the wafer 1, and the fan 70 at the position where it does not overlap with the wafer 1. The drive signal DR2 is output to. Further, for example, in the state before the wafer 1 is taken out from the containment vessel 2 or the state immediately after the wafer 1 is housed in the containment vessel 2, the wafer 1 is not held by the robot 20. In this case, the control unit 71 outputs the drive signal DR2 to each of the plurality of fans 70. By the drive control of the fan 70 by the control unit 71, a downflow is formed directly under the wafer 1 shown in FIG. 3, and the turbulence of the air flow in the region not overlapping with the wafer 1 can be suppressed.

The second rotation speed includes a rotation speed of zero, in other words, a speed at which the fan 70 stops. When the fan 70 is stopped, a downflow is formed through the gap between the fans 70 or around the fan 70. However, from the viewpoint of surely preventing the formation of a region where gas stays directly under the fan 70, the fan 70 that does not overlap with the wafer 1 is rotated at a low speed (slow speed) that does not stop. Is particularly preferable.

Further, as a modification to the present embodiment, a sensor 72 is provided in the vicinity of the hand portion 22 shown in FIG. 4, and it is detected whether or not the hand portion 22 holds the wafer 1 (see FIG. 1), and the wafer 1 is used. There is also a method of outputting the drive signal DR1 shown in FIG. 5 to all the fans 70 when is detected. In this case, when the wafer 1 is held, each of the plurality of fans 70 rotates at the first rotation speed, and when the wafer 1 is not held, each of the plurality of fans 70 rotates at the second rotation speed. Rotate (or stop rotation). Even in the case of this modification, the turbulence of the air flow can be suppressed as compared with the case where each of the plurality of fans 70 is constantly rotating.

However, from the viewpoint of suppressing the turbulence of the air flow and surely preventing the particles from rolling up, even when the wafer 1 is held, the fan 70 arranged at a position not overlapping with the wafer 1 is the second fan 70. It is preferable to rotate (or stop) at the rotation speed of. As described above, in the case of the present embodiment, among the plurality of fans 70, the rotation speed of the fan 70 overlapping the wafer 1 is faster than the rotation speed of the fan 70 not overlapping the wafer 1. The drive signals DR1 and DR2 are transmitted so as to be. As a result, it is possible to suppress the turbulence of the air flow and surely prevent the particles from rolling up.

Further, as shown in FIG. 3, each of the plurality of fans 70 is attached at a position closer to the hand portion 22 than the bottom portion 32 of the clean chamber 30. In this case, the separation distance between the wafer 1 and the fan 70 can be reduced. By reducing the separation distance between the fan 70 and the wafer 1 in this way, a downflow can be reliably formed in the region directly below the wafer 1.

<Modification example 1>
Hereinafter, a plurality of types of modifications of the wafer transfer device 10 described with reference to FIGS. 1 to 5 will be described. FIG. 6 is a plan view showing a modified example of the transport mechanism portion shown in FIG. FIG. 7 is a modification of FIG. 3, and is a cross-sectional view of a wafer transfer device having a transfer mechanism portion shown in FIG. The robot 20A shown in FIG. 6 differs from the robot 20 shown in FIG. 4 in the mounting method of the fan 70.

Specifically, the arm portion 23 included in the robot 20A shown in FIG. 6 is supported on the support portion 25 in a state of being rotatable in the horizontal direction. This point is the same as that of the robot 20 shown in FIG. The second blower mechanism portion of the robot 20A has a fan 70 that is attached to the support portion 25 and is supported in a rotatable state following the rotational movement of the arm portion 23. The fan 70 follows the rotational movement of the arm portion 23 and rotates in the horizontal direction along the rotation direction 20D2. Therefore, the robot 20A is different from the robot 20 shown in FIG. 4 in that one fan 70 is attached to the support portion 25.

As shown in FIG. 7, the wafer transfer device 10A having the robot 20A is provided with only one fan 70 that follows the rotational operation of the hand portion 22. The fan 70 is always directly below the wafer 1 while the hand portion 22 holds the wafer 1. Further, while the hand portion 22 holds the wafer 1, the fan 70 as the second blower mechanism is not arranged at a position where it does not overlap with the wafer 1. The control by the control unit 71 (see FIG. 5) included in the wafer transfer device 10A is simpler than the control by the control unit 71 included in the wafer transfer device 10 shown in FIG.

That is, for example, the sensor 72 attached to the fan 70 shown in FIG. 7 continuously detects whether or not the wafer 1 is held by the hand portion 22. When one wafer 1 is taken out from the containment vessel 2 and is sucked and held by the hand unit 22, the sensor 72 shown in FIG. 5 outputs a detection signal SG1 indicating that the wafer 1 is held. The control unit 71 that has received the detection signal SG1 outputs the drive signal DR1 to the fan 70. As a result, the fan 70 rotates at the first rotation speed so that a downflow to the extent that gas does not stay is formed directly under the wafer 1. Next, when the wafer 1 is handed over to the alignment unit 60 (see FIG. 1), the sensor 72 outputs a detection signal SG2 which means that the wafer 1 is not held. The control unit 71 that has received the detection signal SG2 outputs the drive signal DR2 to the fan 70. As a result, the fan 70 rotates (or stops rotating) at a second rotation speed that is slower than the first rotation speed. After the alignment process is completed, when the hand unit 22 (see FIG. 7) holds the processed wafer 1 (see FIG. 7) again, the sensor 72 outputs the detection signal SG1. Similarly thereafter, the control unit 71 outputs the drive signal DR1 when the hand unit 22 holds the wafer 1, and outputs the drive signal DR2 when the hand unit 22 does not hold the wafer 1.

In the case of the wafer transfer device 10A, by the above control, a downflow is always formed directly under the wafer 1, and when the wafer 1 is not held, the turbulence of the air flow can be prevented.

In the case of the wafer transfer device 10A as well, the fan 70 is attached to a position closer to the hand portion 22 than the bottom portion 32 of the clean chamber 30 as in the wafer transfer device 10 shown in FIG. As a result, an air flow can be generated in the vicinity of the wafer 1, so that gas retention under the wafer 1 can be prevented. In the example shown in FIG. 6, the support portion 25 of the robot 20A has a cylindrical shape. In this case, when the fan 70 rotates around the support portion 25 along the rotation direction 20D2, there is an advantage that a part of the fan 70 is unlikely to enter the inside (blind spot) of the support portion 25. In this case, the fan 70 can be arranged near the support portion. However, as a modification with respect to FIG. 6, the shape of the support portion 25 may be a square pillar as in the robot 20 shown in FIG. The wafer transfer device 10A shown in FIG. 7 is the same as the wafer transfer device 10 shown in FIG. 3, except for the above-mentioned differences. Therefore, duplicate description will be omitted.

<Modification 2>
FIG. 8 is a plan view showing another modification of the transport mechanism portion shown in FIG. FIG. 9 is another modification with respect to FIG. 3, and is a cross-sectional view of a wafer transfer device having a transfer mechanism portion shown in FIG. The robot 20B shown in FIG. 8 differs from the robot 20 shown in FIG. 4 and the robot 20A shown in FIG. 6 in the mounting method of the fan 70.

Specifically, the robot 20B as a transfer mechanism unit included in the wafer transfer device 10B shown in FIG. 9 rotates horizontally on the support portion 25 and between the arm portion (first arm portion) 23 and the support portion 25. An arm portion (second arm portion) 26 supported in a possible state and a fan 70 supported by the arm portion 26 are provided. In the example shown in FIG. 8, each of the arm portion 23 and the arm portion 26 is mounted on a turntable 24 rotatably configured in the rotation direction 20D2 (see FIG. 1), and the support portion 25 is provided via the turntable 24. Supported by. Similar to the example described with reference to FIG. 4, the arm portion 23 directs the hand portion 22 connected to the arm portion 23 by changing the angles of the plurality of plate-shaped members 23 m with the joint portion 23j as the rotation axis. It can be expanded and contracted along 22D1. On the other hand, the arm portion 26 does not expand and contract along the direction 22D1.

For example, when the hand portion 22 of the robot 20B shown in FIG. 9 extends toward the containment vessel 2 along the direction 22D1 (see FIG. 8), the arm portion 26 that supports the fan 70 does not expand and contract. As a result, when the wafer 1 is delivered to and from the containment vessel 2, the delivery operation is not hindered by the fan 70. Further, since the arm portion 26 is fixed on the turntable 24, if the turntable 24 rotates, the arm portions 23 and 26 rotate together with the turntable 24. That is, the fan 70 supported by the arm portion 26 rotates following the rotational operation of the arm portion 23. As a result, while the wafer 1 is held by the hand portion 22, the fan 70 can always be maintained in a state of being arranged directly under the wafer 1. However, as described above, during the transfer of the wafer 1 between the robot 20B and another mechanical unit (for example, the containment vessel 2, the alignment unit 60 shown in FIG. 1, or the processing chamber 3), There may be a timing when the fan 70 does not exist directly under the wafer 1.

As shown in FIG. 9, the wafer transfer device 10B having the robot 20B is provided with only one fan 70 that follows the rotational operation of the hand portion 22. While the hand portion 22 holds the wafer 1, the fan 70 as the second blower mechanism is not arranged at a position where it does not overlap with the wafer 1. The control by the control unit 71 (see FIG. 5) included in the wafer transfer device 10B is simpler than the control by the control unit 71 included in the wafer transfer device 10 shown in FIG.

That is, for example, the sensor 72 attached to the fan 70 shown in FIG. 9 continuously detects whether or not the wafer 1 is held by the hand portion 22. When one wafer 1 is taken out from the containment vessel 2 and is sucked and held by the hand unit 22, the sensor 72 shown in FIG. 5 outputs a detection signal SG1 indicating that the wafer 1 is held. The control unit 71 that has received the detection signal SG1 outputs the drive signal DR1 to the fan 70. As a result, the fan 70 rotates at the first rotation speed so that a downflow to the extent that gas does not stay is formed directly under the wafer 1. Next, when the wafer 1 is handed over to the alignment unit 60 (see FIG. 1), the sensor 72 outputs a detection signal SG2 which means that the wafer 1 is not held. The control unit 71 that has received the detection signal SG2 outputs the drive signal DR2 to the fan 70. As a result, the fan 70 rotates (or stops rotating) at a second rotation speed that is slower than the first rotation speed. After the alignment process is completed, when the hand unit 22 (see FIG. 7) holds the processed wafer 1 (see FIG. 9) again, the sensor 72 outputs the detection signal SG1. Similarly thereafter, the control unit 71 outputs the drive signal DR1 when the hand unit 22 holds the wafer 1, and outputs the drive signal DR2 when the hand unit 22 does not hold the wafer 1.

In the case of the wafer transfer device 10B, by the above control, a downflow is always formed directly under the wafer 1, and when the wafer 1 is not held, the turbulence of the air flow can be prevented.

In the case of the wafer transfer device 10B, the arm portion 23 and the arm portion 26 are mounted on the support portion 25, respectively. Therefore, in the case of the wafer transfer device 10B, the separation distance between the fan 70 and the wafer 1 can be made smaller than that of the wafer transfer device 10 shown in FIG. 3 and the wafer transfer device 10A shown in FIG. 7. .. As a result, an air flow can be generated in the vicinity of the wafer 1, so that gas retention under the wafer 1 can be prevented.

In the example shown in FIG. 9, the support portion 25 of the robot 20B is a square pillar. However, similarly to the robot 20A shown in FIG. 6, the shape of the support portion 25 may be a cylinder. In this case, when the fan 70 rotates around the support portion 25 along the rotation direction 20D2, it is possible to prevent a part of the fan 70 from overlapping with a part of the support portion 25. The wafer transfer device 10B shown in FIG. 9 is the same as the wafer transfer device 10 shown in FIG. 3, except for the above-mentioned differences. Therefore, duplicate description will be omitted.

<Modification example 3>
FIG. 10 is a flow chart showing a modified example of control of a plurality of fan driving states by the control unit shown in FIG. The control method shown in FIG. 10 is different from the method shown in FIG. 5 in that the monitoring method when controlling the rotation speeds of the plurality of fans 70 shown in FIG. 1 is different.

Specifically, in the case of the control method shown in FIG. 10, a sensor 73 for detecting the position of the hand portion 22 (see FIG. 4) of the robot 20 shown in FIG. 1 and a sensor 72 for detecting the presence / absence of wafer holding by the hand portion 22. Has. In the case of this modification, one sensor 72 and one sensor 73 may be used. The sensor 73 is, for example, an image sensor, which detects the position of the hand unit 22 of the robot 20 on the traveling shaft 21 shown in FIG. 1 and transmits the position information signal SG3 to the control unit 71. Further, the sensor 72 is attached in the vicinity of the hand unit 22 shown in FIG. 4, for example, detects whether or not the wafer 1 is held by the hand unit 22, and transmits the detection signals SG1 and SG2 to the control unit 71.

The control unit 71 processes the position information signal SG3 received from the sensor 73 as data, and determines the position of the hand unit 22 (see FIG. 4) of the robot 20 shown in FIG. From this determination result, it is specified which fan 70 among the plurality of fans 70 the hand unit 22 overlaps with.

Next, the control unit 71 determines whether or not the wafer 1 (see FIG. 1) is held based on the detection signal SG1 or SG2 received from the sensor 72. Then, the drive signal DR1 or DR2 is output to each of the plurality of fans 70 based on the result of specifying the position of the hand unit 22 and the result of determining whether or not the wafer is held. Specifically, the drive signal DR1 is output to the fan 70 overlapping the wafer 1, and the drive signal DR2 is output to the other fans 70. As a result, the drive signal DR1 can be selectively output to the fan 70 that overlaps with the wafer 1 in the same manner as the control method described with reference to FIG.

In the case of this modification, it is not necessary to attach the sensors 72 to each of the plurality of fans 70, so that the number of sensors 72 can be reduced.

<Modification example 4>
Further, although not shown, as another modification of the control method, the control unit 71 may control the driving state of the fan 40 shown in FIGS. 3, 7, or 9. In the case of the control method shown in FIGS. 5 and 10, the control unit 71 controls only the driving state of the fan 70. In the case of this modification, the control unit 71 controls the driving state of the fan 40 in addition to the driving state of the fan 70. Although each of FIGS. 2, 3, 7, and 9 shows an example in which one fan is mounted on the filter 50, a plurality of fans 40 may be arranged on the filter 50. In this case, the airflow in the clean chamber 30 can be finely controlled by individually controlling the rotation speeds of the plurality of fans 40.

In the case of this modification, based on the detection signals SG1 and SG2 shown in FIGS. 5 and 10 or the position information signal SG3 shown in FIG. 10, the control unit 71 drives the fan 70 and the fan 40 (rotational speed, or , Can be rephrased as the unit time air flow). As a result, the airflow in the clean chamber 30 can be finely controlled according to the presence / absence of holding the wafer by the hand unit 22 and the position of the wafer 1.

Further, although various modification examples have been described above, each modification example can be appropriately combined and applied.

Although typical modifications of the present embodiment have been described above, the present invention is not limited to the above-mentioned examples and typical modifications, and various modifications can be made without departing from the spirit of the invention. Applicable.

The present invention can be used in a wafer transfer device.

1 Wafer 1t upper surface (first main surface)
1b lower surface (second main surface)
2 Containment vessel 3 Processing chamber 4 Processing equipment 10, 10A, 10B Wafer transfer equipment 20, 20A, 20B Robot (conveyance mechanism, transfer robot)
20D1,22D1 Direction 20D2 Rotational direction 21 Traveling shaft 22 Hand part 23,26 Arm part 23j Joint part 23m Plate-shaped member 24 Rotating table 25 Support part (stage)
30 Clean room (clean room)
31 Ceiling 31H, 32H, 34, 35 Opening 32 Bottom 40, 70, 70A, 70B, 70C Fan 50 Filter 60 Alignment unit (alignment mechanism)
71 Control units 72, 72A, 72B, 72C, 73 Sensors DR1, DR2 Drive signal SG1, SG2 Detection signal SG3 Position information signal

Claims (6)

A transport mechanism unit for transporting a wafer having a first main surface and a second main surface opposite to the first main surface, and
A clean room having a ceiling and a bottom facing the ceiling,
A first blower mechanism unit that is attached to the ceiling portion and forms an air flow from the ceiling portion side to the bottom portion side of the clean room.
Have,
The transport mechanism unit
A hand portion that holds the wafer with the first main surface of the wafer facing the ceiling portion, and a hand portion.
A first arm portion that supports the hand portion and operates the hand portion,
A support portion that supports the first arm portion and
When the hand portion holds the wafer, the second blower mechanism portion that forms an air flow from the second main surface side of the wafer toward the bottom portion of the clean chamber, and
A control unit that controls the driving state of the second blowing mechanism unit according to the presence or absence of the wafer being held by the hand unit, and a control unit.
A wafer transfer device. In the wafer transfer device according to claim 1,
The first arm portion is supported on the support portion so as to be rotatable in the horizontal direction.
The second blower mechanism portion has a plurality of fans attached to the support portion, and has a plurality of fans.
The control unit is a wafer transfer device that transmits a drive signal so that the rotation speed of the fan overlapping the wafer among the plurality of fans is faster than the rotation speed of the fan not overlapping the wafer. In the wafer transfer device according to claim 2,
A wafer transfer device in which each of the plurality of fans is attached to a position closer to the hand portion than the bottom portion of the clean chamber. In the wafer transfer device according to claim 1,
The first arm portion is supported on the support portion so as to be rotatable in the horizontal direction.
The second blower mechanism portion has a fan that is attached to the support portion and is supported in a rotatable state following the rotational operation of the first arm portion.
The control unit is a wafer transfer device that transmits a drive signal so that the rotation speed increases when the fan overlaps the wafer and the rotation speed decreases when the fan does not overlap the wafer. In the wafer transfer device according to claim 4,
A wafer transfer device in which the fan is attached at a position closer to the hand portion than the bottom portion of the clean chamber. In the wafer transfer device according to claim 1,
The first arm portion is supported on the support portion so as to be rotatable in the horizontal direction.
The second blower mechanism unit
A second arm that is supported on the support portion and between the first arm portion and the support portion so as to be rotatable in the horizontal direction.
A fan as the second blowing mechanism supported by the second arm, and
With
The control unit is a wafer transfer device that transmits a drive signal so that the rotation speed increases when the fan overlaps the wafer and the rotation speed decreases when the fan does not overlap the wafer.

Images