JP2016124140A - Transfer device and transfer method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a transfer device and a transfer method for abutting two platelike bodies on each other to transfer a target article, capable of improving throughput of transfer processing by optimizing time from the abutment of a roller member on the platelike body to the start of movement.SOLUTION: A first platelike body SB and a second platelike body BL are held by setting one main surfaces close to and oppositely to each other, a roller member 431 extending along the other main surface opposite the one main surface of the second platelike body BL is brought into contact with the other main surface, the second platelike body BL is pressed to the first platelike body SB by the roller member 431 using a driving force generated by driving force generation means 436, and the roller member 431 is moved along the other main surface while the second platelike body BL is pressed to the first platelike member SB by the roller member 431. The load of the driving force generation means 436 is detected, and after the detected load of the driving force generation means 436 reaches a predetermined threshold value, the movement of the roller member 431 is started.SELECTED DRAWING: Figure 1

Description

  The present invention relates to a transfer apparatus and a transfer method for transferring a transfer object from one plate-like body to the other plate-like body by bringing two plate-like bodies into contact with each other.

  As a technique for forming a pattern or thin film on a plate such as a glass substrate or a semiconductor substrate, the two plates are brought into contact with each other, and the pattern or thin film supported on the main surface of one plate is Some transfer the transferred object to the other plate-shaped body. For example, in the technique disclosed in Patent Document 1 previously disclosed by the applicant of the present application, a blanket carrying a pattern on a surface and a substrate are arranged to face each other, and the blanket is pushed up by a long roller member and brought into contact with the substrate. Then, the roller member moves along the blanket while pushing up the blanket, whereby the pattern is transferred from the blanket to the substrate.

JP 2014-144628 A

  Thus, in the technique in which two plate-like bodies are brought into contact with each other by pressing using a roller member, two plate-like bodies are formed after the roller member pushes up one plate-like body due to elasticity of each member or the like. A time delay inevitably occurs before a constant and uniform pressing force acts between the bodies. On the other hand, in order to allow the transfer to proceed satisfactorily, the roller member needs to move while the plate-like body is pressed with a constant pressing force. Therefore, it is necessary to provide a certain waiting time after the roller member comes into contact with the plate-like body and starts to move along the surface of the plate-like body, and this causes a decrease in the throughput of the transfer process. Can be. This is because if the roller member starts moving with insufficient pressure, problems such as air bubbles being caught between the two plate-like bodies can be avoided reliably, and the characteristics of each member can vary. This is because it is necessary to provide a considerably long waiting time in order to cope with the problem.

  For this reason, it is desired to improve the processing throughput by optimizing the waiting time described above, but the above-described conventional technology does not consider this problem and does not have a configuration that can meet the above-described requirements. It was.

  The present invention has been made in view of the above problems, and in a transfer apparatus and a transfer method for transferring an object to be transferred by bringing two plate-like bodies into contact with each other, the roller member moves after contacting the plate-like body. The purpose is to optimize the time to start and improve the throughput of the transfer process.

  In order to achieve the above object, the transfer device according to the present invention has a first holding means for holding the first plate-like body and a second plate-like body, one main surface of which is one main main body of the first plate-like body. A second holding means that holds the second plate in close proximity to the surface, and extends along the other main surface opposite to the one main surface of the second plate-like body, abuts against the other main surface, and A roller member that moves along the other main surface while pressing the two plate-like members against the first plate-like body, and a driving force for moving the roller member away from and in contact with the other main surface are generated. A driving force generating means; a detecting means for detecting a load of the driving force generating means; and a moving means for moving the roller member along the other main surface, wherein the roller member is attached to the second plate-like body. From the state of being opposed to each other, the driving force generating means causes the roller member to move to the second plate-like body. Then, after the load of the driving force generating means detected by the detecting means reaches a predetermined threshold, the moving means moves the roller member. Start.

  In addition, in order to achieve the above object, the transfer method according to the present invention brings two plate-like bodies into contact with each other, and the transfer object carried on one main surface of one of the plate-like bodies is transferred to the other of the above-mentioned objects. In the transfer method for transferring to one main surface of the plate-like body, the first plate-like body and the second plate-like body, which are the two plate-like bodies, are held with the one main surface being closely opposed to each other. And a roller member extending along the other main surface opposite to the one main surface of the second plate-like body is brought into contact with the other main surface, and the driving force generating means generates the driving force. An initial abutting step of pressing the second plate-shaped body against the first plate-shaped body by a roller member; and pressing the second plate-shaped body against the first plate-shaped body by the roller member, A moving step of moving along the other main surface, and in the initial contact step, the driving force generation Detecting a load of the unit, after the load of the driving force generating means to be detected has reached a predetermined threshold value, the moving process is started.

  In the invention configured as described above, the load of the driving force generating means for generating the driving force for pressing the roller member against the second plate body and pressing it against the first plate body is detected, and the detection result Based on the above, the movement start timing of the roller member is determined. In the process in which the roller member approaches and comes into contact with the second plate-like body, the load of the driving force generating means is generally constant and relatively light. On the other hand, in the process in which the roller member comes into contact with the second plate-like body and pushes up the second plate-like body and presses it against the first plate-like body, the load of the driving force generating means gradually increases. When the second plate-like body is pressed against the first plate-like body with a constant pressing force, the load of the driving force generating means also has a constant magnitude.

  From this, it can be estimated that the pressing force between the first plate-like body and the second plate-like body has reached a desired magnitude as the load of the driving force generating means that gradually increases reaches a predetermined value. Is possible. Therefore, by setting an appropriate threshold value in advance and starting the movement of the roller member after the load of the driving force generating means reaches the threshold value, it is possible to reliably prevent transfer defects caused by insufficient pressing force. Thus, the roller member can be moved. Further, it is not necessary to provide a waiting time longer than necessary, and it is possible to optimize the waiting time and improve the throughput of the transfer process.

  As described above, according to the present invention, the movement of the roller member after the load of the driving force generating means for generating the driving force for causing the roller member to approach the second plate-like body exceeds a predetermined threshold value. Is started. Therefore, it is possible to improve the throughput of the transfer process by optimizing the waiting time until the roller member starts to move while preventing the transfer failure.

1 is a side view schematically showing an embodiment of a transfer apparatus according to the present invention. It is a figure which shows the structure of the principal part of this transfer apparatus. It is a figure which shows a transfer roller block. It is a flowchart which shows the transfer process by this transfer apparatus. FIG. 6 is a first diagram schematically showing the position of each part in the course of transfer processing. It is a 2nd figure which shows typically the position of each part in the process of a transfer process. It is a timing chart which shows operation | movement of a transfer process. It is a figure explaining the initial contact step of a transfer roller and a blanket. It is a figure explaining the advantage of torque control. It is a figure which shows the modification of a roller unit.

  FIG. 1 is a side view schematically showing an embodiment of a transfer apparatus according to the present invention. FIG. 2 is a diagram showing the configuration of the main part of the transfer apparatus. In order to uniformly indicate the directions in each figure, XYZ orthogonal coordinate axes are set as shown in FIG. Here, the XY plane represents a horizontal plane and the Z axis represents a vertical axis. More specifically, the (+ Z) direction represents a vertically upward direction.

  The transfer device 1 has a structure in which an upper stage block 2, a lower stage block 3, and a transfer roller block 4 are attached to a main frame (not shown). In addition to the above, the transfer apparatus 1 includes a control unit 9 that controls each part of the apparatus according to a processing program stored in advance and executes a predetermined operation.

  First, the overall configuration of the apparatus 1 will be described. As the detailed structure of the upper stage block 2 and the lower stage block 3, for example, the structure described in the above-mentioned Patent Document 1 (Japanese Patent Laid-Open No. 2014-144628) can be used. I will explain only.

  The transfer device 1 is a device that performs pattern formation by bringing the blanket BL held by the lower stage block 3 and the plate PP or substrate SB held by the upper stage block 2 into contact with each other. More specifically, the pattern forming process by the apparatus 1 is as follows. First, the coated layer carried on the blanket BL is patterned by bringing a plate PP created corresponding to the pattern to be formed into contact with the blanket BL on which the pattern forming material is uniformly applied (see FIG. Patterning process). Then, by bringing the blanket BL thus patterned and the substrate SB into contact, the pattern carried on the blanket BL is transferred to the substrate SB (transfer process). As a result, a desired pattern is formed on the substrate SB.

  As described above, the transfer apparatus 1 can be used for both the patterning process and the transfer process in the pattern forming process for forming a predetermined pattern on the substrate SB, but is used in a mode in which only one of these processes is performed. May be. It can also be used for the purpose of transferring the thin film carried on the blanket BL to the substrate SB. Hereinafter, the configuration and operation of the apparatus will be described on the assumption that the pattern or thin film formed on the surface of the blanket BL is transferred to the substrate SB. However, the operation in the patterning process is also described by replacing the substrate SB with the plate PP. Is done.

  The upper stage block 2 includes an upper stage 21 whose bottom surface is a flat substrate holding surface 21a. The upper stage 21 is attached to the lower part of the beam member 22 extending in the Y direction, and is held by the beam member 22 so that the substrate holding surface 21a is in a horizontal posture. The beam member 22 is held up and down in the vertical direction (Z direction) by a pair of stage elevating mechanisms 23 and 23 arranged separately in the Y direction. Thereby, the upper stage 21 is movable in the Z direction.

  In this embodiment, a ball screw mechanism is used as an example of the stage elevating mechanism 23, but is not limited to this. The stage elevating mechanism 23 includes a ball screw 233 that is rotatably supported with respect to the main frame by support members 231 and 232, a motor 234 that rotates the ball screw 233, and a nut portion 235 attached to the ball screw 233. . The ball screw 233 and the motor 234 are connected via a coupling 236. The motor 234 is controlled by a stage lift control unit 91 provided in the control unit 9, and the upper stage 21 moves up and down by the motor 234 rotating in accordance with a control signal from the stage lift control unit 91.

  Although not shown in the drawing, suction grooves or suction holes are provided on the lower surface (substrate holding surface) 21 a of the upper stage 21, and negative pressure is applied from the suction control unit 92 provided in the control unit 9 as necessary. Supplied. Accordingly, the upper stage 21 can suck and hold the upper surface of the substrate SB that is in contact with the substrate holding surface 21a. The planar size of the substrate holding surface 21a is formed slightly smaller than the size of the substrate SB to be held.

  The upper stage block 2 configured as described above holds the substrate SB in a horizontal posture. The substrate SB is carried into the apparatus 1 so that the transfer surface onto which the pattern or thin film is to be transferred faces downward. Further, the stage elevating mechanism 23 moves the upper stage 21 up and down, so that the gap between the blanket BL and the substrate SB held on the lower stage described below is adjusted to a specified value.

  The lower stage block 3 is disposed below the upper stage 21, and includes a lower stage 31 provided with an opening 311 at the center and a blanket holding surface 31a having a flat and horizontal upper surface. The lower stage 31 is supported by a plurality of support columns 32. The planar size of the lower stage 31 is larger than the size of the blanket BL to be held, and the opening size of the opening 311 is larger than the planar size of the substrate SB. As a result, the blanket BL is held by the lower stage 31 with only the peripheral edge thereof in contact with the lower stage 31 and the central part with the lower surface opened. A suction groove 312 is provided in a region of the upper surface (blanket holding surface) 31a of the lower stage 31 in contact with the blanket BL. A negative pressure is supplied to the suction groove 312 from the suction control unit 92 of the control unit 9 as necessary. Thereby, the blanket BL is sucked and held on the lower stage 31. The blanket BL is held in a horizontal posture with the carrying surface carrying the pattern or thin film to be transferred to the substrate SB facing upward.

  The support column 32 that holds the lower stage 31 is attached to an alignment stage (not shown). The alignment control unit 93 provided in the control unit 9 drives the alignment stage, so that the lower stage 31 is in a horizontal plane (XY plane). Move in. Thereby, the relative position in the horizontal direction between the substrate SB held on the upper stage 21 and the blanket BL held on the lower stage 31 is optimized.

  The lower stage block 3 further includes a pair of elevating hand units 33 and 34 provided to face each other with an interval in the X direction. The elevating hand unit 33 and the elevating hand unit 34 have shapes symmetrical to each other with respect to the YZ plane, but their structures are basically the same.

  The lifting / lowering hand unit 33 faces the opening 311 of the lower stage 31 and is provided with a plurality of (four here as an example) lifting / lowering hands 331, 332, 333, and 334 provided in order along the Y direction. And a drive unit 335 for individually raising and lowering the hand. Similarly, the elevating hand unit 34 includes elevating hands 341, 342, 343, and 344 provided in order along the Y direction facing the opening 311 of the lower stage 31, and a drive unit that individually elevates and lowers these elevating hands. 345. The drive units 335 and 345 are controlled by a hand lifting control unit 94 provided in the control unit 9 and individually control the vertical position of each lifting hand according to a control signal from the hand lifting control unit 94.

  Each lifting hand is positioned at a position where the upper surface thereof is flush with the substrate holding surface 31a of the lower stage 31, so that the lower surface of the central portion of the blanket BL held by the lower stage 31 with the lower surface opened is removed. Support auxiliary. Thereby, it is possible to support the blanket BL flatly while suppressing the bending thereof. Further, by retracting downward as necessary, interference with the transfer roller traveling described below is avoided.

  The transfer roller block 4 is fixed to the main frame below the lower stage 31, extends in the Y direction, a ball screw mechanism 42 provided along the guide rail 41, and a nut portion 425 of the ball screw mechanism 42. And a roller unit 43 attached thereto.

  FIG. 3 is a view showing a transfer roller block. More specifically, FIG. 3A is a perspective view showing the structure of the transfer roller block 4, and FIG. 3B is a view showing the positional relationship between the transfer roller block 4 and the lifting hand units 33 and 34. is there. In the transfer roller block 4, a ball screw mechanism 42 is provided along the guide rail 41. More specifically, the ball screw 423 is supported by support members 421 and 422 provided near both ends of the guide rail 41, and the ball screw 423 is rotated by the motor 424 through the coupling 426. A nut portion 425 is attached to the ball screw 423. As the motor 424 rotates, the motor 424 moves horizontally along the nut portion 425 guide rail 41 in the Y direction.

  The roller unit 43 attached to the nut portion 425 includes a transfer roller 431 formed in a roller shape having the X direction as a longitudinal direction. The transfer roller 431 is supported by a support member 432 so as to be rotatable around a rotation axis parallel to the X direction. The surface of the transfer roller 431 is formed of an elastic body, for example, a rubber material, and the length of the transfer roller 431 in the X direction is longer than the length of the substrate SB in the X direction.

  Further, a ball screw mechanism as a roller lifting mechanism for lifting the transfer roller 431 is attached to the nut portion 425. More specifically, a ball screw 434 is rotatably supported on a frame extending upward from the nut portion 425, and the nut portion 435 is attached to the ball screw 434. The ball screw 434 is supported with the vertical direction as an axial direction, and is coupled by a motor 436 via a coupling 437 and is driven to rotate by the motor 436. That is, when the motor 436 rotates the ball screw 434, the nut portion 435 moves up and down in the vertical direction. The ball screw 434, the nut portion 435, the motor 436, and the coupling 437 together constitute a ball screw mechanism.

  A support member 432 is attached to an arm extending from the nut portion 435. The arm and the support member 432 may be integrally formed. When the motor 436 rotates the ball screw 434, the transfer roller 431 moves up and down together with the nut portion 435. As a result, the transfer roller 431 moves toward and away from the lower surface of the blanket BL held on the lower stage 31. That is, the ball screw mechanism (the ball screw 434, the nut portion 435, the motor 436, and the coupling 437) functions as a roller lifting mechanism. The motor 436 is controlled by a roller lifting control unit 95 provided in the control unit 9.

  The roller unit 43 having such a configuration moves in the Y direction by the rotation of the motor 424. The motor 424 is controlled by a roller travel control unit 97 provided in the control unit 9. When the motor 424 rotates according to a control signal from the roller travel control unit 97, the nut portion 425 of the ball screw mechanism 42 moves in the Y direction along the guide rail 41, and the roller unit 43 is moved along with the movement of the nut portion 425. Move. As a result, the transfer roller 431 provided in the roller unit 43 travels in the Y direction along the lower surface of the blanket BL. Thus, the guide rail 41 and the ball screw mechanism 42 have a function as a roller traveling mechanism that causes the transfer roller 431 to travel in the Y direction.

  As described above, the transfer roller 431 can perform the up and down operation in the Z direction by the roller lifting mechanism and the traveling operation in the Y direction by the roller traveling mechanism. When the transfer roller 431 (roller unit 43) travels in the Y direction, interference between the elevating hands 331 and the like provided in the elevating hand units 33 and 34 and the roller unit 43 is avoided as follows. Hereinafter, the positional relationship between the pair of lifting hands 331 and 341 provided in the lifting hand units 33 and 34 and the roller unit 43 will be described as an example, but the same applies to other lifting hands.

  As shown in FIG. 3B, the roller unit 43 moves in the Y direction so that the transfer roller 431 is along the lower surface of the blanket BL held by the lower stage 31. In the X direction, the tips of the lifting hands 331 and 341 arranged opposite to each other are separated from each other, and the roller lifting mechanism (the ball screw 434, the nut portion 435, and the motor 436) of the roller unit 43 travels through these gaps. . Therefore, the interference between the roller lifting mechanism and the lifting hands 331 and 341 is structurally avoided.

  On the other hand, when the lifting hands 331 and 341 are in contact with or close to the lower surface of the blanket BL, the lifting hands 331 and 341 may come into contact with the transfer roller 431 and the support member 432. This problem is addressed by lowering the elevating hands 331 and 341 integrally until the upper surface thereof is positioned below the lower surface of the support member 432. That is, in synchronization with the traveling of the roller unit 43 in the Y direction, the elevating hand units 33 and 34 sequentially retract the elevating hands 331 and the like downward. As a result, the transfer roller 431 and the support member 432 pass through the upper part of the lifting hand 331 and the like, and interference between the roller unit 43 and the lifting hand 331 and the like is avoided.

  Returning to FIG. 1, the description of the configuration of the transfer apparatus 1 will be continued. A torque detector 438 is connected to the motor 436 that constitutes the roller travel mechanism. The torque detector 438 detects the load torque applied to the motor 436 directly or indirectly, and the detection method is arbitrary. For example, a torque sensor built in the motor 436 may be used, and the generated torque of the motor 436 may be obtained from the amount of current flowing into the motor 436.

  The torque detection signal output from the torque detection unit 438 is input to the torque determination unit 96 provided in the control unit 9. As will be described later, the torque determination unit 96 controls the operation of the roller unit 43 according to the load torque of the motor 436 by controlling the roller lifting control unit 95 and the roller travel control unit 97 based on the detected torque value.

  Next, transfer processing by the transfer device 1 configured as described above will be described. As described above, a transfer process for transferring a pattern or a thin film from the blanket BL to the substrate SB will be described here, but the operation in the patterning process is also described by replacing the substrate SB with the plate PP.

  FIG. 4 is a flowchart showing transfer processing by this transfer apparatus. FIG. 5 and FIG. 6 are diagrams schematically showing the position of each part in the course of the transfer process. FIG. 7 is a timing chart showing the operation of the transfer process.

  In the transfer process, first, a substrate SB to which a pattern or a thin film is to be transferred is carried into the apparatus and set on the upper stage 21 (step S101). The upper stage 21 sucks and holds the substrate SB with the transfer surface onto which the pattern or thin film is transferred facing downward. Subsequently, the blanket BL carrying the pattern or thin film to be transferred to the substrate SB is carried into the apparatus and set on the lower stage 31 (step S102). The lower stage 31 sucks and holds the blanket BL with the carrying surface carrying the pattern or thin film facing upward.

  Next, each part of the apparatus is positioned at a predetermined initial position (step S103). FIG. 5A shows the initial position of each part. In the upper stage 21 and the lower stage 31, the substrate SB and the blanket BL are opposed in parallel with a predetermined gap therebetween, and the pattern PT or thin film carried on the blanket BL and the substrate SB are predetermined in the horizontal direction. It is positioned so as to be in a positional relationship. Further, the lifting hand 331 and the like rise to a position where the upper surface thereof is flush with the upper surface of the lower stage 31, and abut against the lower surface of the blanket BL to support the blanket BL in a horizontal posture. The roller unit 43 is positioned at a position immediately below one end of the substrate SB in the Y direction and at a retreat position where the transfer roller 431 is retracted sufficiently downward from the lower surface of the blanket BL.

  From this state, the transfer roller 431 rises and contacts the lower surface of the blanket BL. Specifically, as shown in FIG. 7, at time T0, the motor 436 constituting the roller raising / lowering mechanism is operated to bring the transfer roller 431 into contact with the transfer roller 431 above the retracted position and slightly below the lower surface of the blanket BL. The position is increased to a previous position at a predetermined first speed V1 (step S104). The motor control at this time is position control or speed control. At this time (time T1 in FIG. 7), the upper end of the transfer roller 431 is not in contact with the blanket BL.

  When the transfer roller 431 reaches the pre-contact position (time T1 in FIG. 7), the rotation of the motor 436 is decelerated, and the rising speed of the transfer roller 431 is changed to the second speed V2 that is lower than the first speed V1 (step). S105). Thereby, the transfer roller 431 further rises at a low speed, and the upper end thereof contacts the lower surface of the blanket BL (time T2 in FIG. 7).

  Torque detection by the torque detector 438 is started by the time when the rising speed is changed to the second speed V2 at the latest (step S106). As shown in FIG. 7, the load torque of the motor 436 detected by the torque detector 438 shows a relatively small constant value until the transfer roller 431 contacts the blanket BL, and the transfer roller 431 contacts the blanket BL. After time T2, it gradually rises. In this way, torque detection is performed at any time, and the transfer roller 431 continues to rise until the torque detection value reaches a predetermined threshold value Tth (step S107).

  As the transfer roller 431 continues to rise after contacting the lower surface of the blanket BL, as shown in FIG. 5B, the blanket BL is pushed up by the transfer roller 431, and finally the upper surface of the blanket BL is the substrate SB. Contact the lower surface. As a result, the pattern or thin film PT carried on the upper surface of the blanket BL adheres to the substrate SB. Further, the transfer roller 431 pushes up the blanket BL, whereby the pattern or the thin film PT is pressed against the substrate SB. Thus, the pattern or the thin film PT is transferred to the substrate SB. In order to satisfactorily transfer the pattern or the thin film PT to the substrate SB, the transfer roller 431 needs to press the blanket BL against the substrate SB with a constant pressing force.

  As shown in FIG. 7, the transfer roller 431 rises at a relatively high speed from the retracted position to the pre-contact position, and rises toward the blanket BL at a relatively low speed after passing through the pre-contact position. It is necessary to move the transfer roller 431 from the retracted position to the pre-contact position by raising the transfer roller 431 at a relatively high speed by position control or speed control until the pre-contact position where the transfer roller 431 and the blanket BL do not contact. Time can be shortened. Further, by lowering the rising speed after the pre-contact position, problems such as the transfer roller 431 violently colliding with the blanket BL or pressing the blanket BL or the substrate SB with excessive pressing force can be avoided. Thus, by setting the rising speed to two stages, it is possible to appropriately proceed the transfer process while shortening the processing time.

  In the process in which the transfer roller 431 contacts and pushes up the blanket BL and further contacts the blanket BL, the load torque of the motor 436 gradually increases. When the detected torque value reaches threshold value Tth (YES in step S107, time T3 in FIG. 7), control of motor 436 is changed to torque control (step S108). Thereafter, the roller lifting control unit 95 controls the motor 436 based on the output from the torque determination unit 96 so that the load torque of the motor 436 becomes a constant target value Ttgt. Thereby, the pressing force between the blanket BL and the substrate SB can be kept constant.

  At time T3 or later, the motor 424 constituting the roller travel mechanism is turned on, and travel of the transfer roller 431 in the Y direction is started (step S109). As a result, the transfer roller 431 travels in the Y direction while being driven and rotated in contact with the lower surface of the blanket BL.

  As shown in FIGS. 5C and 6A, the transfer roller 431 moves in the Y direction while pressing the blanket BL against the substrate SB, so that the blanket BL and the substrate SB pass through the pattern or the thin film PT. The contact area spreads in the Y direction. In this way, the pattern or the thin film PT is sequentially transferred to the substrate SB (transfer process). The transfer roller 431 rises to a pressing position where the blanket BL can be pressed with a constant pressing force, and travels in the Y direction in this state.

  At this time, in order to avoid interference with the traveling roller unit 43, the elevating hand mechanisms 33 and 34 move the elevating hands 331 (341), 332 (342), 333 (343), and 334 (344) to the roller unit 43. As it moves, it will descend sequentially.

  The roller unit 43 continues to travel until the transfer roller 431 reaches the end position immediately below the other end of the substrate SB (step S110). As a result, the entire substrate SB contacts the blanket BL, and the transfer of the pattern or the thin film PT to the substrate SB is completed. At this time, the movement of the roller unit 43 is stopped, and as shown in FIG. 6C, the roller unit 43 is separated from the blanket BL and retracts downward (step S111). The blanket BL and the substrate SB that are brought into close contact with each other are integrally carried out (step S112), and the transfer process in the transfer device 1 is completed.

  Next, the meaning of the threshold value Tth determined for the torque detection value will be described. This threshold value Tth is set in order to define the timing at which the roller traveling mechanism operates and the roller unit 43 starts traveling in the Y direction. That is, in this embodiment, the roller unit 43 starts running after the load torque of the motor 436 detected by the torque detector 438 reaches the threshold value Tth. As will be described below, in the initial contact stage where the transfer roller 431 starts to contact the blanket BL, the roller unit 43 travels after the pressing force of the transfer roller 431 to the blanket BL becomes constant in the X direction. This is to get started.

  FIG. 8 is a diagram illustrating an initial contact stage between the transfer roller and the blanket. As exaggeratedly shown in FIG. 8 (a), the transfer roller 431 is formed on the support member 432 in the form of an upwardly convex bow so that the central portion in the X direction slightly protrudes toward the blanket BL compared to the end portion. It is supported. This is because the contact between the blanket BL and the substrate SB pushed up by the transfer roller 431 in the initial contact stage starts from the central portion in the X direction and spreads to the end portion. This is to prevent bubbles from entering between the gaps (more precisely, between the pattern supported on the blanket BL or the thin film PT and the substrate SB).

  In the initial contact stage, the transfer roller 431 starts to contact the blanket BL from the vicinity of the center in the X direction as shown in FIG. As the transfer roller 431 rises, the contact range widens toward both ends, and finally the blanket BL is pressed evenly in the entire area in the X direction as shown in FIG. 8B.

  A pressing force received from the transfer roller 431 between a central point Pa that contacts the transfer roller 431 at a relatively early stage on the lower surface of the blanket BL and a point Pb near the end that contacts the transfer roller 431 later. Compare (surface pressure). As shown in FIG. 8 (c), at the point Pa, the increase of the surface pressure starts at a relatively early timing and approaches a constant value as the contact range widens with time, whereas at the point Pb, the surface pressure increases. The rise of the rise and the asymptotic approach to a constant value are more delayed.

  In order to start the movement of the transfer roller 431 in a state where a uniform surface pressure is applied to the blanket BL in the X direction, it is necessary to wait for the surface pressure at the point Pb near the end to sufficiently increase. However, it is difficult to determine this timing from the position of the transfer roller 431 in the Z direction and the rising speed of the transfer roller 431. In particular, when the surfaces of the transfer roller 431 and the blanket BL are elastic, there is a time delay for the pressing force to be transmitted to the contact point between the blanket BL and the substrate SB, so that the transfer roller 431 reaches the pressing position. It becomes more difficult to grasp the timing from when the contact pressure is equalized.

  In a simple manner, it is possible to equalize the surface pressure by providing a relatively long time interval from when the transfer roller reaches the pressing position to when it starts running. However, this increases the processing waiting time and decreases the throughput. Further, the surface pressure may not be an appropriate value due to variations in the thickness of the blanket BL or the substrate SB.

  On the other hand, paying attention to the load torque of the motor 436 that generates a driving force for raising and lowering the transfer roller 431, the load torque increases in the process from the start of pressing to the point Pa until the surface pressure is equalized to the point Pb. Continue. From this, if the value of the load torque of the motor 436 when the surface pressure at the point Pb reaches a predetermined value is obtained in advance, it is possible to know the timing at which the predetermined surface pressure is applied to the point Pb from the detected value of the load torque. It becomes possible. In other words, by determining the travel start timing of the transfer roller 431 based on the detected value of the load torque, it is possible to start the travel of the transfer roller 431 with an equal pressing force applied between the blanket BL and the substrate SB. it can.

  The threshold value Tth of the detected torque value is experimentally determined in advance as the magnitude of the load torque of the motor 436 when a sufficient pressing force is applied to the end portion Pb of the blanket BL in the initial contact stage. Therefore, in the transfer device 1, the transfer roller 431 can start running with an equal pressing force applied between the blanket BL and the substrate SB in the initial contact stage. Thereby, the transfer quality can be improved. Further, if the running of the transfer roller 431 is started immediately after the detected torque value reaches the threshold value Tth, useless waiting time can be shortened and processing throughput can be improved.

  After the detected torque value reaches the threshold value Tth, the motor 436 is torque-controlled. By controlling the motor 436 so that the load torque becomes constant, it is possible to prevent an excessive pressing force from being applied to the blanket BL and the substrate SB. Torque control may be started before the detected torque value reaches the threshold value Tth. For example, as indicated by a dotted arrow in FIG. 7, the torque control is performed at time T1 when the transfer roller 431 reaches the pre-contact position. May be started. In this way, the transfer roller 431 rises at a relatively high speed until the load torque approaches the threshold value Tth, and the time until the transfer roller 431 starts to travel can be further shortened.

  On the other hand, when the rising speed of the transfer roller 431 after the pre-contact position is set to a low speed as in this embodiment, it is possible to prevent application of excessive pressing force due to overshoot of the control system. Also in this case, the subsequent pressing force can be kept constant by performing torque control without delay when the detected torque value reaches the threshold value Tth.

  The target value Ttgt in the torque control is set as a torque value necessary for applying a predetermined pressing force between the blanket BL and the substrate SB. The target value Ttgt and the threshold value Tth may be the same value, or the threshold value Tth may be set as a value slightly smaller than the target value Ttgt. For example, in a system in which some overshoot is allowed in the pressing force between the blanket BL and the substrate SB, the target value Ttgt and the threshold value Tth can be made the same. On the other hand, in a system in which overshoot is not allowed, the threshold value Tth can be slightly smaller than the target value Tgt, for example, 90% of the target value Tgt.

  Further, the following advantages can be obtained by controlling the torque of the motor 436 while the transfer roller 431 is running.

  FIG. 9 is a diagram illustrating the advantage of torque control. As shown in FIG. 9A, a case is considered where the lower surface of the blanket BL is not flat, and the position fluctuates in the Z direction. Such a case can actually occur due to the flatness of the substrate holding surface 21a of the upper stage 21, the thickness variation of the substrate SB and the blanket BL, warpage, and the like. In such a case, position control that keeps the height (Z-direction position) of the transfer roller 431 constant cannot follow such position fluctuations as shown by the dotted line in FIG. 9B. As a result, the pressing force fluctuates.

  On the other hand, when torque control is performed, as shown by a solid line in FIG. 9B, the height of the transfer roller 431 changes corresponding to the position fluctuation of the blanket BL, but the torque detection value is constant. Thus, the pressing force is kept constant by controlling the motor 436. Thereby, the blanket BL and the substrate SB are pressed with a constant pressing force, and the transfer of the pattern or the like from the blanket BL to the substrate SB can be favorably progressed. This means that the processing accuracy required for the upper stage 21 is lower than that in the form in which position control is performed, which is advantageous in reducing the apparatus cost.

  As described above, in the transfer device 1 of this embodiment, the load torque of the motor 436 that generates the driving force for raising and lowering the transfer roller 431 that pushes up the blanket BL and contacts the substrate SB is detected. Based on the detection result, the travel start timing of the transfer roller 431 along the blanket BL is determined. Specifically, the transfer roller 431 is controlled to start running when the detected torque value that increases as the blanket BL is pushed up exceeds a predetermined threshold value Tth. The threshold value Tth is determined in advance as a load torque value when the pressing force (surface pressure) applied from the transfer roller 431 to the blanket BL in the initial contact stage becomes substantially constant in the X direction.

  Therefore, the transfer roller 431 can be started to run with a uniform and sufficient pressing force applied from the transfer roller 431 to the blanket BL, and the transfer quality can be maintained well. In addition, it is possible to improve the throughput of processing by eliminating unnecessary waiting time.

  As described above, in the above embodiment, the substrate SB corresponds to the “first plate-like body” of the present invention, the lower surface thereof corresponds to “one main surface”, and the upper surface corresponds to “the other main surface”. . The blanket BL corresponds to the “second plate-like body” of the present invention, the upper surface thereof corresponds to “one main surface”, and the lower surface corresponds to “other main surface”. Further, the pattern or the thin film PT corresponds to the “transfer object” of the present invention.

  In the above embodiment, the upper stage 21 functions as the “first holding means” of the present invention, and the substrate holding surface 21a corresponds to the “contact surface” of the present invention. Further, the lower stage 31 functions as the “second holding means” of the present invention. The transfer roller 431 functions as the “roller member” of the present invention, and the motor 436 functions as the “driving force generating means” and the “motor” of the present invention. The torque detector 438 functions as the “detecting means” of the present invention. Further, the guide rail 41 and the ball screw mechanism 42 constituting the roller traveling mechanism are integrated to function as the “moving means” of the present invention.

  In this embodiment, the retracted position of the transfer roller 431 corresponds to the “first position” of the present invention, and the pre-contact position corresponds to the “second position” of the present invention. In FIG. 7, the distance D1 between the retracted position and the lower surface of the blanket corresponds to the “first distance” of the present invention, and the distance D2 between the position before contact and the lower surface of the blanket corresponds to the “second distance” of the present invention. ing.

  In the transfer process shown in FIG. 4, steps S101 and S102 correspond to the “holding step” of the present invention, and steps S103 to S107 correspond to the “initial contact step” of the present invention. Steps S109 to S111 correspond to the “movement process” of the present invention.

  The present invention is not limited to the above-described embodiment, and various modifications other than those described above can be made without departing from the spirit of the present invention. For example, the torque detection unit 438 detects the load torque of the motor 436 that functions as the “driving force generating means” of the present invention, but the means for detecting the magnitude of the load of the driving force generating means is not limited to this. . For example, the following may be performed.

  FIG. 10 is a view showing two modified examples of the roller unit. In these modified examples, instead of detecting the load torque of the motor 436 by the torque detector 438, means for detecting the pressure when the transfer roller 431 presses the blanket BL is provided. In FIG. 10, the same or corresponding components as those of the roller unit 43 of the above embodiment shown in FIG. The configurations other than those described below are the same as those in the above embodiment, and thus the description thereof is omitted.

  In the first modification shown in FIG. 10A, a pressure sensor 441 is disposed between the support member 432 that supports the transfer roller 431 and the nut portion 435 of the roller lifting mechanism. In the second modified example shown in FIG. 10B, a pressure sensor 442 is disposed between the frame 433 of the roller lifting mechanism and the nut portion 425 of the roller traveling mechanism. Outputs of these pressure sensors 441 and 442 are input to a pressure determination unit 98 provided in the control unit 9. The pressure determination unit 98 is provided in place of the torque determination unit 96 of the above-described embodiment, and controls the roller lifting control unit 95 and the roller travel control unit 97 based on outputs from the pressure sensors 441 and 442.

  In these modified examples, the load amount of the motor 436 is represented by the magnitude of the pressure detected by the pressure sensors 441 and 442. Also with these configurations, detection values of the pressure sensors 441 and 442 when a uniform surface pressure is applied to the blanket BL in the initial contact stage are obtained in advance, and a threshold value is set, and increases as the transfer roller 431 rises. By starting the running of the transfer roller 431 when the detected pressure value to be reached reaches the threshold value, the same effect as in the above embodiment can be obtained. In these aspects, the pressure sensors 441 and 442 function as the “detecting means” of the present invention.

  In addition, the “driving force generating means” in the above embodiment is a motor that generates a rotational force, but the source of the driving force for driving the transfer roller 431 to move up and down is not limited to such a rotational motor. Various power sources whose output can be appropriately adjusted based on the reference signal can be used as the “driving force generating means” of the present invention. For example, a linear motor can be used.

  Moreover, in the said embodiment, when the transfer roller 431 raises toward the blanket BL, the raising speed is changed in two stages, but this is not an essential requirement. For example, if the torque control is performed when the transfer roller 431 reaches the pre-contact position, it is not necessary to control the rising speed. Further, torque control with speed limitation may be performed. When a means for detecting that the transfer roller 431 is in contact with the blanket BL is provided, the start timing of the torque control may be set as time T2 when the transfer roller 431 is in contact with the blanket BL.

  The above embodiment is a transfer device for transferring a transfer object such as a pattern carried on the blanket BL to the substrate SB. However, the technical idea of the present invention is limited to the transfer device for transferring such a pattern or the like. For example, the present invention can also be applied to a technique of bonding two plate-like bodies without using a pattern or the like.

  As described above, the specific embodiment has been described by way of example. In the present invention, for example, the driving force generating means is a motor that generates a rotational force, and the detecting means is configured to detect the load torque of the motor. May be. By converting the rotational motion of the motor into motion in an appropriate direction by the conversion mechanism, the roller member can be moved up and down using the rotational force of the motor as a driving force. Various methods for detecting the load torque of the motor have been established, and using such a technique, it is possible to optimize the movement start timing of the roller member.

  For example, after the moving unit starts moving the roller member, the output of the driving force generating unit may be controlled so that the load of the driving force generating unit becomes constant. By controlling the output of the driving force generating means so that the magnitude of the load becomes constant, the roller member can be pressed against the second plate-like body with a constant pressing force. Thereby, the first plate-like body and the second plate-like body are pressed against each other with a constant pressing force, and transfer defects due to fluctuations in the pressing force can be prevented, and the transfer object can be transferred well. it can.

  Further, for example, the driving force generating means moves the roller member from the first position where the interval between the roller member and the second plate-like body is the first interval to the second position where the interval is a second interval smaller than the first interval. A configuration may be adopted in which the roller member is moved at a first speed toward the second plate-like body, and the roller member is moved at a second speed lower than the first speed when the second position is reached. When the roller member comes into contact with the second plate-like body, it is necessary to move the roller member at a relatively low speed in order to prevent the roller member from violently colliding with the second plate-like body. On the other hand, by moving the roller member at a relatively high speed at a stage where the distance from the second plate-like body is relatively large, the time until the roller member comes into contact with the second plate-like body can be shortened. By switching the speed of the roller member in this way, the roller member can be brought into contact with the second plate-like body in a short time, and collision with the second plate-like body can be avoided.

  For example, the 2nd holding means may be the composition which holds the peripheral part of the 2nd plate-like object in the state where the central part of the other principal surface of the 2nd plate-like object was opened. By doing so, the second plate-like body can be held by the second holding means while the roller member moves in contact with the other main surface of the second plate-like body. As a result, it is possible to perform the transfer satisfactorily while keeping the posture of the second plate-like body properly.

  Further, for example, the second holding unit may be configured to hold the second plate-like body in a horizontal posture with one main surface of the second plate-like body facing upward. In this case, the roller member comes into contact with the lower surface (the other main surface) of the second plate-like body, and the second plate-like body is pushed up and brought into contact with the first plate-like body. When the lower surface side is opened to receive the contact of the roller member, the second plate-like body may bend downward. However, since the second plate-like body is bent in a direction in which the interval with the first plate-like body is widened, There is no unexpected contact between the first plate-like body and the second plate-like body. Therefore, it is possible to prevent occurrence of transfer failure due to unexpected contact, and it is possible to reduce a predetermined interval between the first plate and the second plate, so that the first plate at the time of transfer The positional deviation between the sheet-like body and the second plate-like body can be suppressed, and the transfer position accuracy can be improved.

  Further, for example, the first holding means may have a flat contact surface that contacts the other main surface opposite to the one main surface of the first plate-like body. The first plate member receives pressure from the roller member via the second plate member. By bringing the first plate-like body into contact with the flat surface, it is possible to prevent the first plate-like body from being bent by pressing from the roller member, and to proceed the transfer favorably.

  For example, the surface of the roller member may be formed of an elastic body. According to such a configuration, a uniform pressing force can be applied to the second plate-like body by the elasticity of the roller member. However, due to the elasticity, there is a time delay from when the roller member is pressed until the pressing force is equalized. By applying the present invention in such a case, the movement of the roller member can be started after the pressing force is equalized.

  The present invention can be suitably applied to a process of transferring an object to be transferred such as a pattern or a thin film onto various substrates such as a glass substrate and a semiconductor substrate.

1 Transfer device 21 Upper stage (first holding means)
21a Substrate holding surface (contact surface)
31 Lower stage (second holding means)
41 Guide rail (moving means)
42 Ball screw mechanism (moving means)
43 Roller unit 431 Transfer roller (roller member)
436 motor (driving force generating means, motor)
438 Torque detection unit (detection means)
441,442 Pressure sensor (detection means)
BL blanket (second plate)
PT pattern or thin film (transferred material)
SB substrate (first plate)
S101, S102 Holding process S103-S107 Initial contact process S109-S111 Movement process

Claims (11)

First holding means for holding the first plate-like body;
A second holding means for holding the second plate-like body in a state in which one main surface thereof is closely opposed to one main surface of the first plate-like body;
The second plate-like body extends along the other main surface opposite to the one main surface, contacts the other main surface and presses the second plate-like body against the first plate-like body while A roller member that moves along the main surface;
Driving force generating means for generating a driving force for moving the roller member away from and in contact with the other main surface;
Detecting means for detecting a load of the driving force generating means;
Moving means for moving the roller member along the other main surface,
From a state in which the roller member is spaced apart from and opposed to the second plate-like body, the driving force generating means moves the roller member toward the second plate-like body to contact the second plate-like body,
A transfer device in which the moving unit starts moving the roller member after the load of the driving force generating unit detected by the detecting unit reaches a predetermined threshold.   The transfer device according to claim 1, wherein the driving force generation unit is a motor that generates a rotational force, and the detection unit detects a load torque of the motor.   3. The control unit according to claim 1, further comprising a control unit configured to control an output of the driving force generation unit so that a load on the driving force generation unit becomes constant after the movement unit starts moving the roller member. Transfer device.   The driving force generating means includes the roller from a first position where a distance between the roller member and the second plate-shaped body is a first distance to a second position where the distance is a second distance smaller than the first distance. 4. The member according to claim 1, wherein the member is moved toward the second plate-like body at a first speed, and when the second position is reached, the roller member is moved at a second speed lower than the first speed. The transfer apparatus according to 1.   5. The transfer device according to claim 1, wherein the second holding unit holds a peripheral portion of the second plate-like body in a state where a central portion of the other main surface is opened.   The transfer device according to claim 1, wherein the second holding unit holds the second plate-like body in a horizontal posture with the one main surface facing upward.   The transfer device according to claim 1, wherein the first holding unit has a flat contact surface that contacts the other main surface opposite to the one main surface of the first plate-like body.   The transfer device according to claim 1, wherein a surface of the roller member is formed of an elastic body. In a transfer method in which two plate-like bodies are brought into contact with each other and a transfer object carried on one main surface of one of the plate-like bodies is transferred to one main surface of the other plate-like body,
A holding step of holding the first plate body and the second plate body, which are the two plate bodies, with the one main surfaces being closely opposed to each other;
A roller member extending along the other main surface opposite to the one main surface of the second plate-like body is brought into contact with the other main surface, and is driven by the roller member by the driving force generated by the driving force generating means. An initial contact step of pressing the second plate-like body against the first plate-like body;
A moving step of moving the roller member along the other main surface while pressing the second plate-like member against the first plate-like member by the roller member,
In the initial contact step, a transfer method is performed in which the load is applied to the driving force generation unit and the moving step is started after the detected load of the driving force generation unit reaches a predetermined threshold.   The transfer method according to claim 9, wherein in the moving step, an output of the driving force generation unit is controlled so that a load of the driving force generation unit is constant.   The roller member is moved at a first speed from a first position where a distance between the roller member and the second plate-like body is a first distance to a second position where the distance is a second distance smaller than the first distance. The transfer method according to claim 9 or 10, wherein the roller member is moved toward a second plate-like body, and when the roller reaches the second position, the roller member is moved at a second speed lower than the first speed.

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