JP2015060946A - Substrate bonding device and substrate bonding method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To align and bond two substrates with high accuracy.SOLUTION: A substrate bonding method comprises: measuring first and second control amounts related to positions of a stationary stage 21 for holding one of two substrates and a movable stage 31 which moves in a stage of holding the other substrate of the two substrates in a manner of opposing the one substrate and contacts the stationary stage 21 via the two substrates; calculating a third control amount by performing filter processing on the measures results; and driving the movable stage 31 by providing the mobile stage 31 (mobile stage drive part 32) with an operation amount calculated by using the third control amount. As a result, by controlling driving (controlling) of the movable stage 31 (movable stage drive part 32) regardless of a contact state between the stationary stage 21 and the movable stage 31, the two substrates can be aligned and bonded with high accuracy.

Description

  The present invention relates to a substrate bonding apparatus and a substrate bonding method for bonding two substrates.

  In recent years, semiconductor device mounting technology has progressed from two-dimensional array mounting in which a plurality of semiconductor chips are arranged in a plane to three-dimensional stacked mounting in which three-dimensional stacking is performed. As a result, the wiring between the semiconductor chips is shortened, the operation speed of the semiconductor device is improved, and the mounting area efficiency of the circuit element mounted on one semiconductor device is dramatically improved.

  Further, in order to improve the performance of the manufacturing cost, the semiconductor device assembly (packaging) technique is not a chip-level assembly technique but a wafer-level assembly technique, that is, a semiconductor substrate (wafer) on which a plurality of circuit elements are formed. ) Is not separated into chips, but the assembly process up to rewiring, resin sealing, and terminal processing is performed in the state of a wafer.

  Under such a background, a substrate bonding apparatus for bonding two substrates such as semiconductor wafers has been developed. Here, the two substrates are bonded together so that a plurality of electrodes formed on their surfaces are bonded to each other. Therefore, in order to accurately position the substrate in the substrate bonding apparatus, a precise and stable control technique for the substrate stage that holds and moves the substrate is required (see, for example, Patent Document 1).

  In the substrate bonding apparatus, the first stage holding one of the two substrates is precisely driven by the second stage that moves while holding the other substrate facing the substrate held by the first stage. By doing so, the two substrates are aligned. Here, in driving of the first and second stages, it has been clarified that resonance occurs when the two substrates come into contact with each other, which becomes an obstacle to precise and stable control of the substrate stage.

US Patent Application Publication No. 2006/0273440

  From the first viewpoint, the present invention is a substrate bonding apparatus for bonding two substrates, the first stage holding one of the two substrates, and the other of the two substrates as the one substrate. And a second stage that contacts the first stage via the two substrates, a first measuring device that calculates a first control amount related to the position of the first stage, and A second measuring device that obtains a second control amount related to the position of the second stage, and obtains a third control amount by filtering the first control amount and the second control amount. And a control unit that drives the second stage by providing the second stage with an operation amount obtained using the control amount.

  Here, the substrate includes not only a substrate such as a semiconductor wafer but also a semiconductor chip, and is not limited to a single-layer semiconductor wafer (or a single-layer semiconductor chip), but includes a plurality of semiconductor wafers (a plurality of semiconductor chips). Also includes stacked semiconductor members. In this specification, the term “substrate” is used as such a concept.

  According to this, it is possible to bond the two substrates in a state where the two substrates are accurately aligned.

  According to a second aspect of the present invention, there is provided a substrate bonding method for bonding two substrates, wherein a control amount relating to a position of a first stage holding one of the two substrates is obtained; Determining the second control amount related to the position of the second stage contacting the first stage via the two substrates, while holding and moving the other substrate opposite the one substrate; Driving the second stage by filtering the first and second control amounts to obtain a third control amount and providing the second stage with an operation amount obtained using the third control amount; , Including a substrate bonding method.

  According to this, it is possible to bond the two substrates in a state where the two substrates are accurately aligned.

It is a figure which shows roughly the structure of the board | substrate bonding apparatus which concerns on one Embodiment. It is a block diagram which shows the main structures of the control system of a board | substrate bonding apparatus. It is a figure for demonstrating the bonding process of a board | substrate. It is a figure for demonstrating the bonding process of a board | substrate. It is a figure for demonstrating the bonding process of a board | substrate. FIGS. 6A and 6B are Bode diagrams showing the frequency response characteristics of the complementary sensitivity function (amplitude and phase) of the feedback control system with one input and one output. FIGS. 7A to 7C are Bode diagrams showing frequency response characteristics of transfer functions (amplitude and phase) expressing the input / output response of the moving stage. It is a Bode diagram which shows the frequency response characteristic of the transfer function (amplitude and phase) expressing the input / output response of a moving stage and a fixed stage. It is a block diagram showing the feedback control system (FS-SRC) of the 1 input 2 output system (SIMO system) corresponding to the moving stage drive part which drives a moving stage. It is a figure which shows the mathematical model expressing the dynamic motion of a fixed stage and a movement stage. It is the table | surface which put together the various parameters in the mathematical model of FIG. It is a Bode diagram which shows the frequency response characteristic of the transfer function (amplitude and phase) expressing the input-output response of a movement stage at the time of applying a FS-SRC type control system and a conventional control system. FIG. 13A to FIG. 13C are Nyquist diagrams when a conventional control system is applied. FIG. 14A to FIG. 14C are Nyquist diagrams when the FS-SRC type control system is applied. 15 (A) and 15 (B) show the complementary sensitivity function (amplitude) when the FS-SRC type control system and the conventional type control system are applied to the bonding of the substrates with the applied pressures 5N and 20N, respectively. FIG. 6 is a Bode diagram showing frequency response characteristics of (and phase). FIGS. 16A and 16B are Nyquist diagrams when the additional gain is not provided and when the additional gain is provided, respectively. It is a block diagram showing the modification of the feedback control system (FS-SRC) of the 1 input 2 output system (SIMO system) of FIG.

  Hereinafter, an embodiment of the present invention will be described with reference to FIGS.

  FIG. 1 schematically shows a configuration of a substrate bonding apparatus 100 according to an embodiment. As will be described later, in this embodiment, microscopes 51 and 52 are provided, and their optical axes (passing through the respective detection centers) are set in the Z axis and in the plane perpendicular to the optical axis in FIG. Are the X-axis direction, the direction perpendicular to the paper surface is the Y-axis direction, and the rotation (tilt) directions around the X-axis, Y-axis, and Z-axis are the θx, θy, and θz directions, respectively.

  The board | substrate bonding apparatus 100 has the frame 10, the fixed stage apparatus 20, the moving stage apparatus 30, the interferometers 41 and 42, and a control system (refer FIG. 2).

  The frame body 10 includes a top plate portion disposed horizontally (parallel to the floor surface) above a floor surface (not shown) parallel to the XY plane, and side wall portions that support ± X end portions of the top plate portion from below. And a bottom plate portion having a surface parallel to the floor surface. A stage surface plate 11 is provided on the bottom plate portion. A guide surface for driving a moving stage 31 described later is formed on the upper surface of the stage surface plate 11. The frame 10 accommodates other components of the substrate bonding apparatus 100.

  The fixed stage device 20 includes a fixed stage 21 that is horizontally disposed below (−Z side) the top plate portion of the frame body 10 and two support members 22 that suspend and support the fixed stage 21 on the top plate portion. Prepare.

  The fixed stage 21 has a suction device (not shown) such as an electrostatic chuck or a vacuum chuck. In FIG. 1 and the like, the fixed stage 21 holds the substrate 1 in the −Z direction by sucking the substrate holder 3 holding the substrate 1 using a suction device.

  The substrate holder 3 (and a substrate holder 4 to be described later) has a holding surface in which an electrostatic chuck or the like for attracting the substrate is embedded, and a magnet piece 5a (magnetic piece 5b) arranged outside the holding surface. . As will be described later, the substrate holders 3 and 4 are bonded using the magnet piece 5a and the magnetic piece 5b in a state where the substrates 1 and 2 held by the magnet holder 5a and the magnetic material piece 5b are bonded together.

  A microscope 51 is fixed downward (toward the −Z direction) on the side of the fixed stage 21. The microscope 51 detects an alignment mark of the substrate 2 held on the moving stage 31 described later.

  On the −X side surface of the fixed stage 21 (the microscope 51 in this embodiment), the reflecting mirror 23 is fixed with its reflecting surface facing the −X direction. Further, on the −Y side surface of the fixed stage 21, a reflecting mirror (not shown) whose longitudinal direction is the X-axis direction is fixed with its reflecting surface facing the −Y direction. These reflecting mirrors are used when measuring the position of the fixed stage 21 using the interferometer 41. Instead of the reflecting mirror, the end surface of the fixed stage 21 may be mirror-finished to form a reflecting surface.

  The two support members 22 include a load cell (not shown) that detects a load applied to the substrate 1 held by the fixed stage 21. The detection result of the load cell is transmitted to the control unit 60.

  The moving stage device 30 includes, for example, an X drive unit 32a that is levitated and supported on the stage surface plate 11 via an air bearing, a Y drive unit 32b disposed thereon, an elevating unit 32c disposed thereon, and a swinging motion. A part 32d and a moving stage 31 supported substantially horizontally by these parts are provided.

  The X drive unit 32a and the Y drive unit 32b include, for example, a linear motor or the like, and move the moving stage 31 (the lifting unit 32c and the swinging unit 32d that support this) along the guide surface of the stage surface plate 11 in the X-axis direction. And it drives with a predetermined stroke in the Y-axis direction.

  The elevating unit 32c includes an actuator (not shown) such as a voice coil motor, for example, and drives the moving stage 31 (oscillating unit 32d) in the Z-axis direction using this. A concave spherical surface is formed on the upper surface of the elevating part 32c.

  The swinging part 32 d supports the moving stage 31. The oscillating portion 32d has a spherical seat formed with a convex spherical surface that abuts the concave spherical surface of the elevating portion 32c. The movable stage 31 is displaced in the θx and θy directions by displacing the spherical seat using the concave spherical surface as a guide. And tilt in the θz direction.

  The above-mentioned X drive unit 32a, Y drive unit 32b, lifting unit 32c, and swing unit 32d constitute a moving stage drive unit 32 (see FIG. 2). By controlling the moving stage driving unit 32, the moving stage 31, that is, the substrate 2 supported on the moving stage 31, is driven in the direction of six degrees of freedom (X, Y, Z, θx, θy, θz) toward the target position. .

  The moving stage 31 has a suction device (not shown) such as an electrostatic chuck or a vacuum chuck. In FIG. 1 and the like, the moving stage 31 holds the substrate 2 in the + Z direction by sucking the substrate holder 4 holding the substrate 2 using a suction device.

  A microscope 52 is fixed upward (toward the + Z direction) on the side of the moving stage 31. The microscope 52 detects the alignment mark of the substrate 1 held on the fixed stage 21.

  A reflecting mirror 33 is fixed to the −X side surface of the moving stage 31 with the reflecting surface facing the −X direction. Further, on the −Y side surface of the movable stage 31, a reflecting mirror (not shown) having the X axis direction as a longitudinal direction is fixed with the reflecting surface facing the −Y direction. These reflecting mirrors are used when measuring the position of the moving stage 31 using the interferometer 42. Instead of the reflecting mirror, the end surface of the fixed stage 21 may be mirror-finished to form a reflecting surface.

  The interferometer 41 emits the measurement beam toward the reflecting mirror 23 in parallel with the X axis, and receives the reflected light from the reflecting mirror 23. The interferometer 41 emits two length measuring beams separated in the X-axis direction toward a reflecting mirror (not shown) fixed to the −Y side surface of the fixed stage 21 in parallel with the Y-axis, and the reflecting mirror. The reflected light from is received. Thereby, the interferometer 41 measures the position (X, Y, θz) of the fixed stage 21 in the XY plane. Further, by adopting a biaxial interferometer as the interferometer 41, the inclination (θx, θy) of the fixed stage 21 is measured.

  The interferometer 42 emits a length measurement beam toward the reflecting mirror 33 parallel to the X axis, and receives the reflected light from the reflecting mirror 33. The interferometer 42 emits two length measuring beams separated in the X-axis direction toward a reflecting mirror (not shown) fixed to the −Y side surface of the moving stage 31 in parallel to the Y-axis. The reflected light from is received. Thereby, the interferometer 42 measures the position (X, Y, θz) of the moving stage 31 in the XY plane. Further, by adopting a two-axis interferometer as the interferometer 42, the inclination (θx, θy) of the moving stage 31 is measured.

  The measurement results of the interferometers 41 and 42 are transmitted to the control unit 60. The control unit 60 drives the moving stage 31 by controlling the moving stage driving unit 32 (X driving unit 32a, Y driving unit 32b, elevating unit 32c, and swinging unit 32d) according to these measurement results.

  FIG. 2 shows the main configuration of the control system of the substrate bonding apparatus 100. This control system is configured around a control unit 60 including a microcomputer (or a workstation) that controls each component in a centralized manner.

  The board | substrate bonding process in the board | substrate bonding apparatus 100 of the above-mentioned structure is demonstrated.

  Prior to the start of the bonding process, as shown in FIG. 1, the moving stage 31 is retracted to the −X side retreat area on the stage surface plate 11. The substrate holder 3 holding the substrate 1 is held on the fixed stage 21, and the substrate holder 4 holding the substrate 2 is held on the moving stage 31. In addition, search alignment is performed for each of the substrates 1 and 2. In addition, baseline measurement is performed to detect a reference mark (not shown) formed on the substrate holder 3 or the fixed stage 21 (substrate holder 4 or the moving stage 31) using the microscope 52 (or the microscope 51). . These details are omitted.

  As shown in FIG. 3, the controller 60 drives the moving stage 31 in the direction of the black arrow (+ X direction), and the microscope 52 fixed thereto faces the substrate 1 held on the fixed stage 21. Move to position. Thereby, at the same time, the microscope 51 fixed to the fixed stage 21 faces the substrate 2 held by the moving stage 31.

  The controller 60 uses the microscope 52 to measure the alignment of the substrate 1 held on the fixed stage 21. Here, a large number of shot regions (circuit pattern regions) are arranged in a matrix on the surface of the substrate 1, and a circuit pattern is formed by exposure in each region, and alignment marks are attached.

  Specifically, the control unit 60 drives the moving stage 31 in the X-axis and Y-axis directions according to the measurement results of the interferometers 41 and 42 (the position of the moving stage 31 with respect to the fixed stage 21), and on the surface of the substrate 1. The alignment mark is positioned in the field of view of the microscope 52. The control unit 60 measures the positioning position of the moving stage 31 and detects the alignment mark using the microscope 52. From the measurement result of the positioning position and the detection result of the alignment mark, the XY position of the detected alignment mark is obtained. The control unit 60 performs the same measurement for two or more alignment marks.

  The controller 60 uses the microscope 51 to measure the alignment of the substrate 2 held on the moving stage 31. Here, like the substrate 1, a large number of shot regions (circuit pattern regions) are arranged in a matrix on the surface of the substrate 2, and a circuit pattern is formed by exposure in each region, and an alignment mark is attached. Has been.

  The controller 60 drives the moving stage 31 in the X-axis and Y-axis directions according to the measurement results of the interferometers 41 and 42 (position of the moving stage 31 with respect to the fixed stage 21) in the same manner as the alignment measurement of the substrate 1, and the substrate 2 An alignment mark on the surface of the microscope is positioned in the field of view of the microscope 51. The control unit 60 measures the positioning position of the moving stage 31 and detects the alignment mark using the microscope 51. From the measurement result of the positioning position and the detection result of the alignment mark, the XY position of the detected alignment mark is obtained. The control unit 60 performs the same measurement for two or more alignment marks.

  The control unit 60 uses the measurement result of the alignment measurement of the substrates 1 and 2 and the measurement result of the baseline measurement (and search alignment) to determine the target position of the moving stage 31 corresponding to the bonding position of the substrates 1 and 2. Ask. As the target position, for example, a position where the square sum of the relative distances in the XY plane between the paired alignment marks is minimized between the alignment marks of the two substrates 1 and 2 is adopted.

  When the target position is determined, as shown in FIG. 4, the control unit 60 controls the moving stage driving unit 32 (X driving unit 32a and Y driving unit 32b) to move the moving stage 31 in the direction of the black arrow (+ X The substrate 2 held on the movable stage 31 is moved to the substrate 1 held on the fixed stage 21 by tilting the moving stage 31 by controlling the swinging part 32d. Align.

  As shown in FIG. 5, the control unit 60 controls the elevating unit 32 c to drive the moving stage 31 in the direction of the black arrow (+ Z direction), thereby bringing the moving stage 31 close to the fixed stage 21, The substrates 1 and 2 held on both stages are overlapped. At this time, the magnet piece 5a on the substrate holder 3 and the magnetic piece 5b on the substrate holder 4 are fixed in a state where the substrates 1 and 2 on which the substrate holders 3 and 4 are superimposed are sandwiched therebetween.

  The controller 60 releases the suction of the substrate holder 3 by the fixed stage 21 and lowers the moving stage 31. As a result, the fixed substrate holders 3 and 4 are separated from the fixed stage 21. Further, the control unit 60 moves the moving stage 31 to the retreat area, releases the adsorption of the substrate holder 4 by the moving stage 31, and attaches the fixed substrate holders 3 and 4 to the substrate pasting using a transfer device (not shown). It is carried out of the combined device 100.

  The board | substrate holders 3 and 4 carried out from the board | substrate bonding apparatus 100 are conveyed by a heating apparatus (not shown), the board | substrates 1 and 2 are bonded together by processes, such as a heating process, and a three-dimensional lamination type is carried out. A semiconductor device is manufactured.

  In the bonding process described above, the control unit 60 controls the moving stage driving unit 32 according to the measurement results of the interferometers 41 and 42 (measurement result of the relative position of the moving stage 31 with respect to the fixed stage 21), and holds the substrate 2. The substrates 1 and 2 are aligned by precisely driving the moving stage 31 with respect to the substrate 1 held on the fixed stage 21. Here, in order to bond the substrates 1 and 2 held on the fixed and moving stages 21 and 31, respectively, when the moving stage 31 is driven and the substrate 2 is pressed against the substrate 1, the moving stage 31 is attached to the substrates 1 and 2. When the moving stage 31 is driven, resonance (resonance mode) is generated. The resonance exhibits various different behaviors depending on the state of the bonding surface depending on the materials of the substrates 1 and 2, the presence / absence and type of the pattern, and the bonding state such as a pressing force (pressing force) applied to the substrates 1 and 2. Such resonance can be an obstacle to precise and stable control of the moving stage 31.

  When a conventional feedback control system (closed loop control system) of a 1-input 1-output system (SISO system) is employed, the control unit 60 uses the interferometers 41 and 42 to control the position (control amount) of the moving stage 31 (control target). The driving force F or the excitation current amount I (operation amount) is obtained from the measurement result and the driving target of the moving stage 31, and the obtained operation amount is sent to the moving stage driving unit 32. The moving stage drive unit 32 supplies, for example, a driving force equal to the driving force F or a current equal to the exciting current amount I to the coils of the linear motor constituting them according to the received operation amount. Thereby, the moving stage 31 is driven toward the driving target.

  6 (A) and 6 (B) show complementary sensitivity when two substrates (made by I company) are pressed against each other with a pressure of 5 N and 20 N in a feedback control system of one input and one output system (SISO system), respectively. The frequency response characteristic of the function T (s) (amplitude (gain) | T (s) | and phase arg (T (s))) is shown. Here, s = jω = j2πf, j = √ (−1), and f is a frequency. The solid line indicates the actual measurement result, and the broken line indicates the result reproduced using a mathematical model described later.

  The complementary sensitivity function T (s) of the SISO feedback control system shows a complicated behavior. At any applied pressure, resonance appears in the vicinity of 20 Hz, 120 Hz, and 130 to 150 Hz. (An anti-resonance appears in the vicinity of 60 Hz.) Of these, the resonance that appears in the vicinity of 20 Hz shows almost the same behavior regardless of the pressure applied to the two substrates. Therefore, it is considered that this resonance is derived from the spring characteristics of the support member 22 that supports the fixed stage 21. The resonance appearing in the vicinity of 120 Hz is not particularly considered in the feedback control in the present embodiment, and is not considered here. It can be confirmed that the resonance appearing in the vicinity of 130 to 150 Hz is shifted in position with respect to the applied pressure of the two substrates. Therefore, this resonance is considered to originate from the joining of two substrates.

  FIGS. 7A to 7C show input / output responses of the moving stage 31 reproduced using a mathematical model to be described later for bonding different substrates (part 1 to part 3). The frequency response characteristics of the transfer function (amplitude and phase) are shown. The solid line indicates the characteristics when the two substrates are pressed against each other with the applied pressure of 5N and the broken line with the applied pressure of 20N.

  By using the mathematical model, in the frequency response characteristics of the transfer function, the resonance derived from the spring characteristic of the support member 22 that appears in the vicinity of 20 Hz, the anti-resonance that appears in the range of 60 to 90 Hz, and the two substrates that appear in the vicinity of 130 to 150 Hz. The resonance derived from the junction is reproduced. The transfer function keeps the amplitude and phase constant in a frequency band of 20 Hz or less, rapidly increases and decreases the amplitude due to resonance in the vicinity of 20 Hz and decreases the phase to 180 degrees, and rapidly increases the amplitude due to anti-resonance at 60 to 90 Hz. As the frequency decreases and increases, the phase is increased to 180 degrees, and further, the amplitude is rapidly increased and decreased by resonance near 130 to 150 Hz, and the phase is decreased to 180 degrees. These indicate continuous peaks, valleys, and mountain shapes and valleys and peaks in the gain diagram and the phase diagram, respectively. That is, the transfer function exhibits a resonance mode in phase with the rigid body mode.

  The resonance that appears in the vicinity of 20 Hz shows almost the same behavior with respect to the type of substrate to be bonded and the applied pressure. On the other hand, the resonance appearing in the vicinity of 130 to 150 Hz shows various behaviors with respect to the types of substrates to be bonded and the applied pressure. In particular, the position is shifted. Therefore, since resonance in the vicinity of 130 to 150 Hz shows different behavior depending on the bonding state of the two substrates, it can be expected that it can be a particularly serious obstacle to precise and stable control of the moving stage 31.

  In the frequency response characteristics of the transfer functions in FIGS. 7A to 7C, resonance behavior is also seen in the high frequency range (near 2000 Hz), but feedback control of the moving stage 31 in the substrate bonding apparatus 100. In addition, since the same behavior is always shown regardless of the bonding state of the substrate, it is not considered here.

  In order to cancel the above-described resonance mode and to precisely and stably drive and control the moving stage 31, using the interferometer 41 (second measuring instrument) in addition to the interferometer 42 (first measuring instrument), one input 2 Build a feedback control system for the output system (SIMO system). In this control system, it is obtained from the measurement result of the interferometer 41 in addition to the relative position of the moving stage 31 with respect to the fixed stage 21 obtained from the measurement result of the interferometers 41 and 42 used in the SISO feedback control system. The position of the fixed stage 21 to be used is used.

  FIG. 8 shows transfer functions P2 and P1 representing input / output responses of the moving stage 31 and the fixed stage 21 reproduced using a mathematical model to be described later with respect to the bonding of the substrate (part 1) with a pressing force of 5N. The frequency response characteristics of (amplitude and phase) are shown. Here, the behavior of the transfer function P2 is equal to that shown in FIG. When the movable stage 31 is driven and the substrate 2 held by the movable stage 31 is brought into pressure contact with the substrate 1 held by the fixed stage 21, the transfer function P1 representing the input / output response of the fixed stage 21 is the input / output of the movable stage 31. A resonance mode that is opposite in phase to the resonance mode indicated by the transfer function P2 that expresses the response (more precisely, a behavior that includes at least the resonance mode of the opposite phase) is shown. In the board | substrate bonding apparatus 100 of this embodiment, the 2nd measuring device (interferometer 41 (reflecting mirror 23)) is installed in the stationary stage 21 which shows the resonance mode (including behavior) of the reverse phase.

FIG. 9 is a block diagram showing a SIMO feedback control system. In this control system, an interferometer 42 (first measuring instrument) that measures the position (first control amount X ₂ ) of the moving stage 31 that is the first control target, and the position of the fixed stage 21 that is the second control target (the first control amount X ₂ ). the interferometer 41 measures a second control amount _{X 1)} (second measurement device), the first and second control amount _(X 2, _{X 1} synthesized and combined control amount measurement results of) a _{(X mix)} The operation amount U is calculated using the generating unit 62 to be generated, the target value R and the generation result of the combined control amount (X _mix ), and the result is transmitted to the moving stage driving unit 32 to drive control the moving stage 31. And a control unit 60. Note that the moving stage 31 is driven by applying a driving force equal to the operation amount U (for example, driving force F) received by the moving stage driving unit 32 to the moving stage 31.

Here, the target value (target trajectory), the controlled variable, the manipulated variable, and the like are defined as functions of time. In FIG. 9 and the description using the same, the Laplace transform is used. Further, the definition of an arithmetic expression U (R−X ₁ , R−X ₂ ) described later is given in the Laplace transform form. Further, hereinafter, unless otherwise specified, the description will be made using Laplace transform (Laplace transform type).

The control unit 60 includes a target generation unit 60a, a subtractor 60b, and a controller 60c. Each of these units may be configured by a microcomputer configuring the control unit 60 and software, or may be configured by hardware. The target generation unit 60a generates a target value of the moving stage 31, here a target position (target value of a position that changes from moment to moment) R, and supplies it to the subtractor 60b. The subtractor 60b calculates a deviation (R−X _mix ) between the target value R and the combined control amount X _mix from the combining unit 62, and supplies it to the controller 60c (transfer function C). The controller 60c calculates the manipulated variable U = C (R−X _mix ) by calculation (control calculation) so that the deviation (R−X _mix ) becomes zero. Here, C is a transfer function of the controller 60c. The transfer function is a Laplace transform ratio R (s) / C (s) of the Laplace transform between the input signal r (t) and the output signal C (t), that is, a Laplace transform function of an impulse response function. The calculated operation amount U is transmitted to the moving stage drive unit 32. Thereby, the moving stage 31 is driven and controlled.

The synthesizer 62 includes a subtractor 62g, proportional devices 62a and 62b, an adder 62c, a high-pass filter 62d, a low-pass filter 62e, and an adder 62f. Subtractor 62g is the interferometer 41 of the measurement results _{X 1} and interferometer 42 the difference between the measurement results _{X 2,} that generates a relative position _X 21 of the movable stage 31 with respect to the fixed stage 21 ₍₌ X 2 -X ₁₎ , And supplied to the proportional device 62b and the low-pass filter 62e. Proportional device (proportional gain beta) 62a is a measurement result _{X 1} of interferometer 41 by multiplying proportional gain beta (.beta.X _1), sent to the adder 62c. Proportional device (proportional gain alpha) 62b is a signal _{X 21} from the subtracter 62g proportional gain alpha times to (.alpha.X _21), sent to the adder 62c. The adder 62c generates the sum (βX ₁ + αX ₂₁ ) of the outputs from the proportional devices 62a and 62b and supplies it to the high-pass filter 62d. The high-pass filter 62d and the low-pass filter 62e have the same cut-off frequency fc, and frequency components F _H (βX ₁ + αX ₂₁ ) higher than the cut-off frequency fc in the signal (βX ₁ + αX ₂₁ ) from the adder 62c, respectively. ) And the frequency component F _L (X ₂₁ ) lower than the cut-off frequency fc in the signal X ₂₁ from the subtractor 62 g is supplied to the adder 62 f. The adder 62f synthesizes signals from the high-pass filter 62d and the low-pass filter 62e to generate a synthesis control amount (also simply referred to as a synthesis amount) X _mix = F _H (βX ₁ + αX ₂₁ ) + F _L (X ₂₁ ) It supplies to the control part 60 (subtractor 60b).

  Specific examples of the high-pass filter 62d and the low-pass filter 62e include a primary filter given by the following equation (1a), a secondary filter given by the equation (1b), and a quaternary filter given by the equation (1c).

However, ω _f = 2πfc.

The composite amount X _mix generated in the feedback control system having the above-described configuration is relative to the fixed stage 21 generated from the position of the mobile stage 31 (first control amount X ₂ ) in the low frequency band without resonance. The position X ₂₁ is βX ₁ + αX _{21 that} is unobservable with respect to resonance in the middle and high frequency bands where resonance exists. Thereby, the transfer characteristics of the moving stage 31 and the combining unit 62 from the input of the manipulated variable U to the output of the combined amount X _mix can be expressed using an ideal rigid body model. Further, since the composite amount X _mix is equal to X ₂₁ in the low frequency band, the controller is used to remove the offset between the reference positions (positions where the reflecting mirrors 23 and 33 are installed) of the position measurement of the interferometers 41 and 42. There is no need to connect a high-pass filter. Furthermore, the control unit 60 can be configured using only the controller 60c designed based on the rigid body model.

  The closed-loop control system (feedback control system) configured as described above is called a frequency separation SRC (FS-SRC) type control system.

  In order to design the proportional devices 62a and 62b constituting the frequency separation SRC (FS-SRC) type control system of the present embodiment, that is, to determine the proportional gains β and α, a simplified mathematical model is used. The dynamic motion of the fixed stage 21 and the moving stage 31 is expressed. For simplicity, translation of the moving stage 31 and the fixed stage 21 in the Y-axis direction is not considered.

  FIG. 10 shows a mathematical model that expresses the dynamic motion of the fixed stage 21 and the movable stage 31. FIG. 11 summarizes various parameters in the mathematical model of FIG.

  The fixed stage 21 is expressed as a rigid body having a mass m0 and an inertia moment J0 that are suspended and supported on the top plate portion of the frame 10 by two springs that simulate the two support members 22. Here, X0 is the position of the center of gravity of the fixed stage 21 in the X-axis direction, 2w0 is the distance between the two support members 22 (springs), LXU is the distance between the center of gravity of the fixed stage 21 and the reflecting mirror 23, and L0U is the fixed stage 21. L0L is the distance from the center of gravity of the fixed stage 21 to the overlapping surface (the surface of the substrate 1 supported by the fixed stage 21).

  Each of the two springs is supported at one point of the top plate portion of the frame 10 and swings in a pendulum shape around the fulcrum. Therefore, the rigid body representing the fixed stage 21 moves not only in the Z-axis direction but also in the X-axis direction by being supported by being suspended by two springs. Correspondingly, the two springs are expressed by using the frictional rigidity k0z and the frictional viscosity C0z relating to the movement in the Z-axis direction and the frictional rigidity k0x and the frictional viscosity C0x relating to the movement in the X-axis direction.

  The moving stage 31 is a rigid body having a mass m2 and an inertia moment J2 supported by a movable stage having a mass m1 simulating the moving stage device 30 via a link having a stiffness kθ and a viscosity Cθ corresponding to the oscillating portion 32e so as to be tiltable. Is expressed as Here, X1 is the position of the center of gravity of the movable stage (swinging part 32e) in the X-axis direction, θ2 is the inclination of the moving stage 31 (tilting angle of the swinging part 32e), and Lx2 is the center of gravity of the moving stage 31 and the swinging axis. L2 is the distance from the center of gravity of the moving stage 31 to the measurement position (the surface of the substrate 2 held by the moving stage 31), and Lx is the distance between the swing axis (link center) and the measurement position. Distance. The movable stage (swinging part 32e) moves in the X-axis direction, and viscosity Cx acts on the movement.

  The moving stage device 30 (lifting part 32 c) drives the moving stage 31 (swing part 32 d) in the Z-axis direction so that the substrate 2 held on the moving stage 31 is pressed against the substrate 1 held on the fixed stage 21. Then, the moving stage 31 contacts the fixed stage 21 through the substrates 1 and 2. This state is expressed as a rigid body simulating the fixed stage 21 and a rigid body simulating the moving stage 31 coupled via a spring and a damper (both not shown). The friction stiffness kwx and friction viscosity Cwx in the X-axis direction acting between the substrates 1 and 2 (between the lower surface of the rigid body simulating the fixed stage 21 and the upper surface of the rigid body simulating the moving stage 31) at this time are expressed. Note that the center of gravity L of the combined body of the fixed stage 21 and the movable stage 31 is used.

  In the mathematical model described above, the moving stage 31 that holds the substrate 2 is driven in the X-axis direction by a driving force (thrust force) Fm. (It is also swung around the swinging shaft (center of the link) by the swinging torque Tty.) D is the height between the center of gravity of the moving stage 31 and the driving position (position where the driving force Fm acts). The difference in height, XU and X2d are the positions of the reflecting mirrors 23 and 33 in the X-axis direction, respectively.

  The values of the various parameters described above are, for example, such that the complementary sensitivity function derived using a mathematical model reproduces the actual measurement result of the frequency response characteristic of the complementary sensitivity function shown in FIG. The transfer function derived using the model is determined using a least square method or the like so as to reproduce the frequency response characteristics of the transfer function shown in FIG.

Note that the frictional stiffness acting between the substrates 1 and 2 is reproduced by reproducing the complementary sensitivity function when the two substrates are pressed against each other with the applied pressures 5N and 20N shown in FIGS. 6A and 6B, respectively. The kwx and the friction viscosity Cwx are determined as kwx = 4 × 10 ⁷ , Cwx = 4500, kwx = 5 × 10 ⁷ , and Cwx = 5500, respectively. It can be seen that the mathematical model parameters (friction stiffness kwx and friction viscosity Cwx) vary depending on the pressure applied to the two substrates.

Using the above mathematical model, input-output response, i.e., the position X ₁ and the moving stage 31 of the fixed stage 21 is a control amount for the thrust Fm acting on the moving stage 31 is an operation amount of the fixed stage 21 and the moving stage 31 The transfer functions P ₁ and P ₂ representing the responses at the position X ₂ are derived. XU = X0−LXU · θ2, X2d = X1 + Lx · θ2 (see FIG. 10). The transfer functions P ₁ and P ₂ can be given in the following general form in the Laplace transform form.

The coefficients b ₁₂ , b ₁₁ , b ₁₀ , b ₂₂ , b ₂₁ , b ₂₀ , a ₀ , a ₁ , a ₂ , a ₃ , a ₄ are derived by deriving the equation of motion using the Lagrange method. .

  In brief, the position X0 of the fixed stage 21 and the position X2d of the moving stage 31 are taken as generalized coordinates x. Using these, the Lagrangian function L (x, v) is derived based on the mathematical model. Where v is the time derivative dx / dt of the generalized coordinate x. By substituting the Lagrangian function L (x, v) into the lower Lagrangian equation (3), a motion equation expressing the mechanical motion of the fixed stage 21 and the moving stage 31 is obtained.

Since the specific form of the coefficient is complicated, in this embodiment, it is determined by simulation or the like, and details are omitted.

In the above-described dynamic model, there are two resonances (frequencies f _p1 and f _p2 ).

As described above, in FIG. 7 (A) ~ FIG 7 (C), the frequency response characteristic of the transfer function P ₂ representing the input-output response of the moving stage 31, which is reproduced using the mathematical model is shown. Details are as described above.

The proportional functions 62a and 62b are designed using the transfer functions P ₁ and P ₂ , that is, the proportional gains β and α (and the transfer function C) are determined. For convenience, the transfer functions P ₁ , P ₂ , C are represented in the fractional form P ₁ = N _P1 / D _P D _R , P ₂ = N _P2 / D _P D _R , C = 1 / D _C. However, it is as follows.

N _P1 = b ₁₂ s ² + b ₁₁ s + b ₁₀ (4a)
N _P2 = b ₂₂ s ² + b ₂₁ s + b ₂₀ (4b)
_{D P D R = a 4 s} 4 + a 3 s 3 + a 2 s 2 + a 1 s 1 + a 0 s 0 ... (4c)
In this case, the characteristic equation A _CL of the closed-loop transfer function for the feedback control system when Fm = 1 is given by the numerator part of the fractional expression of 1 + CβP ₁ + CαP ₂ . That is,
A _CL = D _C D _P D _R + βN _P1 + αN _P2 (5)
In the characteristic equation A _CL , β and α are determined so as to satisfy the following expression (6) using an arbitrary analysis function γ.

βN _P1 + αN _P2 = γD _R (6)

Thus, the open-loop transfer function _{βP 1 + αP 2 = γ /} D C D P are _obtained, P 1, resonant mode indicated by the respective poles (i.e. _P 1, _{P 2} gives the resonance behavior included in each of _{P 2} ) Is zero-zero canceled. Further, D _C and γ are determined so that the characteristic equation A _CL has a stable pole (in this description, it is assumed to be a multiple root for convenience), that is, the following equation (7) is satisfied.

A _CL = (D _C D _P + γ) D _R = (s + ω ₁ ) (s + ω ₂ ) (s + ω _n ) D _R (7)

Next, the proportional gain beta, alpha is, so as not to include _{D R} having singularities (poles), is determined from equation (4a) ~ formula (4c) and (6).

Here, β = β ₁ β ₂ is given, and the coefficients β ₁ and α are determined so as to satisfy the condition β ₁ + α = 1 (β ₂ = 1). However, it is not easy to determine specific forms of the coefficients β ₁ and α for a complicated model such as the mathematical model (see FIG. 10) employed in the present embodiment. In this case, for example, the mass ratio between the fixed stage 21 and the moving stage 31 is given as an initial value to the coefficients β ₁ and α (β ₁ = M ₁ / (M ₁ + M ₂ ), and α = M ₂ / (M ₁ + M _2). )), It may be optimized by a trial and error method so as to improve the stability of the control system.

On the other hand, in the substrate bonding apparatus 100 of the present embodiment, the moving stage 31 is configured to translate by the moving stage apparatus 30 (the X driving unit 32a and the Y driving unit 32b) and to be tilted by the swinging unit 32d. The amplitude (gain) of the transfer function P2 of the moving stage 31 changes according to the distance from the center of the inclination of the measurement points of the total 42 (irradiation point of the length measurement beam on the reflecting mirror 33). Therefore, the coefficient β ₂ (referred to as additional gain) is fixed in the gain of the transfer function P2 of the moving stage 31 in the frequency response characteristics of the gains of the transfer functions P2 and P1 shown in FIG. It is determined so as to match the gain of the transfer function P1 of the stage 21. The effect will be described later.

Some freedom remains in the determination of the remaining D _C , γ. Therefore, for example, a PID controller is designed from the proportional devices 62a and 62b and the controller 60c.

The proportional gains β and α depend only on fixed parameters such as the mass M0 of the fixed stage 21 and the mass M2 of the moving stage 31, and depending on the states of the fixed stage 21 and the moving stage 31, such as the friction stiffness kwx and the friction viscosity Cwx. It does not depend on parameters that can change. This means that the resonance modes of P ₁ and P ₂ are canceled in the closed loop transfer function and are invariant to changes in the state of the fixed stage 21 and the movable stage 31.

  FIG. 12 shows the case where the FS-SRC control system designed as described above is applied (FSSRC) and the case where the conventional control system is applied to the bonding of the substrate (part 3) with a pressure of 5 N. The frequency response characteristic of the transfer function (amplitude and phase) expressing the input / output response of the (non SRC) moving stage 31 is shown. By applying the FS-SRC type control system, it can be confirmed that the resonance appearing in the vicinity of 130 to 150 Hz caused by the bonding of the substrates and the anti-resonance are almost canceled at 60 to 90 Hz.

  The stability of the FS-SRC type control system designed as described above is analyzed by simulation with respect to the bonding of the substrates (No. 1 to No. 3) with the applied pressure of 5N and 20N. Here, the mechanical motions (response characteristics) of the fixed stage 21 and the movable stage 31 are reproduced using the mathematical model described above.

  FIGS. 13A to 13C show Nyquist diagrams in the case where a conventional control system is applied to bonding of three substrates (part 1 to part 3), respectively. For any condition (substrate and applied pressure), the Nyquist locus includes two loops derived from resonance. One of them shows only a part of it in the figure, and it passes through the vicinity of the point (1, 1), the point (0, 0), and the point (0, -1) for each condition. Since the trajectory is traced, it is determined that the resonance is caused by the spring characteristic of the support member 22 that appears in the vicinity of 20 Hz. The other appears at the lower right in the figure, and since the size of the loop varies significantly depending on the applied pressure, it is determined that the resonance is caused by the joining of the two substrates.

  For any of the conditions, the Nyquist trajectory does not surround the point (−1, 0) and passes through the right side thereof, and therefore satisfies the Nyquist stability condition. However, the Nyquist trajectory changes the size of the loop due to resonance originating from the joining of two substrates depending on the conditions, and in particular, for substrate 1 or 3 thereof, it approaches from a point (-1, 0) to a distance of 0.5. To do. In FIG. 13A and other figures, a circle with a radius of 0.5 centering on the point (−1, 0) is drawn as an index of stability. Therefore, although the conventional control system is stable, it is evaluated that its degree is low.

  FIGS. 14A to 14C show Nyquist diagrams when the FS-SRC type control system of this embodiment is applied to bonding of three substrates (part 1 to part 3), respectively. It is shown. However, in any of the figures, the two Nyquist loci for the applied pressures 5N and 20N almost overlap. For any condition (substrate and pressure), the Nyquist locus does not surround the point (−1, 0) and passes through the right side thereof, and thus satisfies the Nyquist stability condition. In any condition, a resonance loop derived from the joining of the two substrates does not appear, and the Nyquist trajectory passes sufficiently far from the point (−1, 0). (In other words, the gain can be increased until the Nyquist trajectory is close to the point (-1, 0).) Therefore, the stability is evaluated to be sufficiently high.

  FIGS. 15A and 15B show the case where the FS-SRC control system and the conventional control system of this embodiment are applied to the bonding of the substrates with the applied pressures 5N and 20N, respectively. The frequency response characteristics of the complementary sensitivity function (amplitude and phase) are shown. By applying the FS-SRC type control system of the present embodiment, the complementary sensitivity function shows a gradual frequency response characteristic for any applied pressure, and the gain is improved by about 5 times.

FIG. 16A and FIG. 16B show the present embodiment in the bonding of the substrates when the additional gain is not provided (β ₂ = 1) and when the additional gain is provided (β ₂ ≠ 1), respectively. The Nyquist diagram in the case of applying the FS-SRC type control system is shown. However, in any of the figures, the two Nyquist loci for the applied pressures 5N and 20N almost overlap. In any case, the Nyquist trajectory does not surround the point (−1, 0) and passes through the right side thereof, and therefore satisfies the Nyquist stability condition. However, when an additional gain is provided (FIG. 16B), when not provided (FIG. 16A), the Nyquist locus is very close to a circle having a radius of 0.5 from the point (−1, 0). Is approaching. In other words, by providing the additional gain, the phase margin is sufficiently improved and a high bandwidth can be added.

  As described above, according to the substrate bonding apparatus 100 according to the present embodiment, the fixed stage 21 that holds one of the two substrates and the other of the two substrates that are held opposite to the one substrate are moved. At the same time, the first and second control amounts related to the positions of the movable stage 31 that contacts the fixed stage 21 via the two substrates are measured, and the third control amount is obtained by filtering these measurement results. The moving stage 31 is driven by giving the moving stage 31 (moving stage driving unit 32) the operation amount obtained using the third control amount. As a result, the two substrates are accurately aligned and bonded together by controlling the driving of the moving stage 31 (moving stage driving unit 32) regardless of the contact state between the fixed stage 21 and the moving stage 31. It becomes possible.

Further, the combined amount X _mix = F _H (βX ₁ + αX) used to obtain the operation amount using the measurement results of the positions (second and first control amounts) X ₁ and X ₂ of the fixed stage 21 and the moving stage 31. ₂₁ ) + F _L (X ₂₁ ), the poles corresponding to the resonance modes included in the transfer functions P ₁ and P ₂ representing the responses of the fixed stage 21 and the moving stage 31 are represented as open loops. It is determined so as to cancel out in the transfer function βP ₁ + αP ₂ . Further, the specific shapes of the transfer functions P ₁ and P ₂ are given using a dynamic model (rigid body model) that expresses the motion of the fixed stage 21 and the movable stage 31 as the motion of two rigid bodies connected by a spring and a damper. As a result, the resonance behaviors (resonance modes) of P ₁ and P ₂ are canceled in the closed-loop transfer function (the resonance mode of P ₂ is canceled by the resonance mode of P ₁ ), and the contact state between the fixed stage 21 and the moving stage 31. Regardless of this, it becomes possible to drive and control (control) the moving stage 31 (moving stage driving unit 32) accurately and stably.

  In addition, the position (first control amount) of the movable stage 31 is measured, and the fixed stage 21 and the movable stage 31 are moved when they are brought into contact with each other in order to bond the substrates held by the fixed stage 21 and the movable stage 31, respectively. The position (second control amount) of the portion of the fixed stage 21 showing the behavior including the resonance mode opposite to the rigid mode indicated by the stage 31 is measured, and the control calculation is performed based on the measurement result and the target value. The operation amount is obtained and the obtained operation amount is given to the moving stage 31 (moving stage driving unit 32), so that the moving stage 31 is driven and controlled. Accordingly, it is possible to accurately and stably drive control (control) the moving stage 31 (moving stage driving unit 32) regardless of the contact state between the fixed stage 21 and the moving stage 31.

  Moreover, since the board | substrate bonding apparatus 100 which concerns on this embodiment is provided with the drive system of the movement stage 31 (movement stage drive part 32) designed as mentioned above, it can drive the movement stage 31 precisely and stably. This makes it possible to improve the bonding accuracy. As a result, for example, large-diameter wafers can be superposed with high accuracy, for example, on the order of 100 nm, and as a result, a three-dimensional stacked semiconductor device with high mounting area efficiency can be efficiently manufactured. .

In the substrate bonding apparatus 100 of the present embodiment, since the position _X 1, _{X 2} each independently fixed stage 21 and the moving stage 31 with the interferometer 41 employs the configuration for measuring, for a fixed stage 21 to constitute a combining unit 62 with a subtractor 62g which generates a relative position _{X 21} of the movable stage 31 (see FIG. 9). Alternatively, for example, such as by irradiating a measurement beam reflector provided on the moving stage 31 from the fixed stage 21, the interferometer for measuring the relative position X ₂₁ by receiving the reflected light (the encoder, the gap sensors, etc. ) was employed, it is also possible to configure the combining unit 62 so as to supply on the measurement result directly proportional device 62b and the low-pass filter 62e to X _21. Further, the combining unit 62 may be configured to process the measurement results X ₁ and X ₂ of the interferometers 41 and 42 to generate a combined amount X _mix = F _H (βX ₁ + αX ₂₁ ) + F _L (X ₂₁ ). Good. Such a case, for example, the interferometer 41 is fed back to the control unit 60 a measurement result _{X 1} of the controller 60c in the operation amount corresponding to the relative positions _{X 21} of the movable stage 31 relative to the fixed stage 21 = C (R- (X _mix -X ₁₎₎ is calculated.

Moreover, it is good also as employ | adopting instead of the synthetic | combination part 62 (refer FIG. 9), and the synthetic | combination part 62 'in the modification of the feedback control system shown by FIG. The synthesizer 62 ′ includes proportional devices 62a and 62b, an adder 62c, a high-pass filter 62d, a low-pass filter 62e, and an adder 62f. Compared with the synthesizer 62, the synthesizer 62 'is configured without the subtractor 62g. In combining unit 62 'of this configuration, the proportional device (proportional gain beta) 62a is a measurement result _{X 1} of interferometer 41 by multiplying proportional gain beta (.beta.X _1), sent to the adder 62c. Proportional device (proportional gain alpha) 62b is the interferometer 42 the measurement result _{X 2} are multiplied proportional gain alpha of (.alpha.X _2), sent to the adder 62c. The adder 62c generates the sum (βX ₁ + αX ₂ ) of the outputs from the proportional devices 62a and 62b and supplies it to the high-pass filter 62d. The high-pass filter 62d and the low-pass filter 62e have the same cut-off frequency fc, and each has a frequency component F _H (βX ₁ + αX ₂ ) higher than the cut-off frequency fc in the signal (βX ₁ + αX ₂ ) from the adder 62c. ) And the frequency component F _L (X ₂ ) lower than the cut-off frequency fc in the measurement result X ₂ of the interferometer 42 is supplied to the adder 62 f. The adder 62f synthesizes the signals from the high-pass filter 62d and the low-pass filter 62e to generate a composite amount X _mix = F _H (βX ₁ + αX ₂ ) + F _L (X ₂ ), and the control unit 60 (subtractor 60b). To supply. Thus, even in the case of adopting the interferometer 41 and 42 of the measurement results _X 1, _{X 2} combining unit 62 of the configuration using the 'without producing relative position _{X 21} of the movable stage 31 with respect to the fixed stage 21, the synthesis Similarly to the case where the unit 62 is employed, it is possible to construct a feedback control system that can precisely and stably drive (control) the moving stage 31 (moving stage driving unit 32).

  Moreover, in the board | substrate bonding apparatus 100 of this embodiment, although the single-axis interferometer which inject | emits one length measuring beam was employ | adopted as the interferometers 41 and 42, it is not restricted to this but two spaced apart in a Z-axis direction ( Alternatively, a multi-axis interferometer that emits parallel measurement beam may be employed. Thereby, the rotation angle (tilt angle) θy around the Y axis of the fixed stage 21 and the movable stage 31 can be further measured. Correspondingly, the moving stage 31 may be driven and controlled using the swing torque Tty (see FIG. 10) around the Y axis of the moving stage 31 as an operation amount.

  In this embodiment, the position is selected as the control amount of the fixed stage 21 and the movable stage 31 that are the control targets. Instead, the measurement amount related to the position, such as speed and acceleration, is selected as the control amount. Also good. In such a case, the speed and acceleration may be calculated and used from the first floor difference or second floor difference calculation of the measurement results of the interferometers 41 and 42. Alternatively, a speed measuring device, an acceleration measuring device, and the like independent from the interferometers 41 and 42 are installed, and speed, acceleration, and the like are measured using them.

  Moreover, in the said embodiment, although the feedback control system of 1 input 2 output system (SIMO system) was constructed | assembled in the board | substrate bonding apparatus 100 which bonds the board | substrates 1 and 2 which each hold | maintains the fixed stage 21 and the movement stage 31, respectively, Not only the bonding device, but the control object physically contacts (or is connected to) another member, and the device whose state can change can also be used for the feedback control system of the 1-input 2-output system (SIMO system) of this embodiment. It is also possible to construct. As a result, the drive control of the control target that is robust in a high band is possible regardless of the contact state (or connected state) of the control target.

  1, 2 ... Substrate, 3, 4 ... Substrate holder, 10 ... Frame, 20 (21, 22, 23) ... Fixed stage device (fixed stage, support member, reflector), 30 (31, 32, 33) ... Moving stage device (moving stage, moving stage drive unit, reflecting mirror), 41 ... interferometer, 42 ... interferometer, 51,52 ... microscope, 60 (62a, 62b, 62d, 62e) ... control unit (proportional unit, proportional Device, high-pass filter, low-pass filter), 100 ... substrate bonding apparatus.

Claims (20)

A substrate bonding apparatus for bonding two substrates,
A first stage for holding one of the two substrates;
A second stage that moves while holding the other of the two substrates opposite to the one substrate, and that contacts the first stage via the two substrates;
A first measuring device for obtaining a first control amount relating to the position of the first stage; and a second measuring device for obtaining a second control amount relating to the position of the second stage, wherein the first control amount and A control unit that drives the second stage by filtering the second control amount to obtain a third control amount, and giving the second stage an operation amount obtained by using the third control amount;
A substrate bonding apparatus comprising: The substrate bonding according to claim 1, wherein the control unit processes the second control amount (X ₂ ) as an amount (X ₂ −X ₁ ) based on the first control amount (X ₁ ). apparatus.   The substrate bonding apparatus according to claim 1, wherein the second measuring device obtains the second control amount based on a position of the first stage.   The first measuring instrument is a portion of the first stage that exhibits a behavior including a resonance mode having a phase opposite to a rigid body mode indicated by the second stage when the second stage contacts the first stage. The board | substrate bonding apparatus as described in any one of Claims 1-3 arrange | positioned. The control unit uses the first and second control amounts (X ₁ , X ₂ ) obtained by the first and second measuring instruments and the first transfer function (β, α) as a composite amount ( X _c = βX ₁ + αX ₂ ) is obtained, and the third control amount is obtained by filtering the combined amount and the measurement result of the second control amount (X ₂ ) by the second measuring instrument. The board | substrate bonding apparatus of description. The first transfer function (β, α) has a pole corresponding to the resonance mode included in each of the second transfer functions (P ₁ , P ₂ ) corresponding to the first and second stages. The substrate bonding apparatus according to claim 5, wherein the substrate bonding apparatus is determined so as to cancel out in a transfer function βP ₁ + αP ₂ of 3. The second transfer function (P ₁ , P ₂ ) uses a dynamic model that expresses the motion of the first and second stages as a motion of at least two or more rigid bodies connected by a spring or a spring and a damper. The board | substrate bonding apparatus of Claim 6 given.   The control unit performs filtering on the combined amount and the second control amount obtained by the second measuring instrument, respectively, and a frequency band in which the resonance mode of the combined amount exists and the second controlled amount. The board | substrate bonding apparatus as described in any one of Claims 5-7 which synthesize | combines with the frequency band in which the said resonance mode does not exist, and calculates | requires the said 3rd control amount.   The substrate bonding according to claim 8, wherein the control unit performs a filtering process on the synthesis amount and the second control amount using a high-pass filter and a low-pass filter having the same cutoff frequency as the high-pass filter, respectively. apparatus.   The substrate bonding apparatus according to claim 5, wherein the first transfer function (β, α) is represented by a gain. A substrate laminating method for laminating two substrates,
Obtaining a control amount relating to the position of the first stage holding one of the two substrates;
The other of the two substrates is moved while being held opposite to the one substrate, and a second control amount related to the position of the second stage contacting the first stage via the two substrates is obtained. And
Driving the second stage by filtering the first and second control amounts to obtain a third control amount and providing the second stage with an operation amount obtained using the third control amount; ,
A substrate bonding method including: The filtering process includes processing the second control amount (X ₂ ) as an amount (X ₂ −X ₁ ) based on the first control amount (X ₁ ). Substrate bonding method.   The substrate bonding method according to claim 11, wherein the second control amount is obtained based on a position of the first stage.   The first control amount is a value of a portion of the first stage that exhibits a behavior including a resonance mode that is opposite in phase to the rigid body mode indicated by the second stage when the second stage contacts the first stage. The board | substrate bonding method as described in any one of Claims 11-13 which is the control amount regarding a position. The third control amount is obtained as a composite amount (X _c = βX ₁ + αX ₂ ) using the first and second control amounts (X ₁ , X ₂ ) and the first transfer function (β, α). The substrate bonding method according to claim 14, which is obtained by filtering the synthesis amount and the second control amount (X ₂ ). The first transfer function (β, α) has a pole corresponding to the resonance mode included in each of the second transfer functions (P ₁ , P ₂ ) corresponding to the first and second stages. The substrate bonding method according to claim 15, wherein the substrate bonding method is determined so as to cancel out at a transfer function βP ₁ + αP ₂ of 3. The transfer function (P ₁ , P ₂ ) is given using a dynamic model that expresses the movement of the first and second stages as a movement of at least two rigid bodies connected by a spring or a spring and a damper. The substrate bonding method according to claim 16. The third control amount is obtained by filtering the composite amount and the second control amount (X ₂ ), respectively, and the frequency band in which the resonance mode of the composite amount exists and the second control amount (X ₂ ). The substrate bonding method according to any one of claims 15 to 17, which is obtained by synthesizing a frequency band in which the resonance mode does not exist as a measurement result. The substrate bonding method according to claim 18, wherein the synthesis amount and the second control amount (X ₂ ) filter processing are performed using a high-pass filter and a low-pass filter having the same cutoff frequency as the high-pass filter, respectively. .   The substrate bonding method according to claim 15, wherein the first transfer function (β, α) is represented by a gain.