JPWO2010038454A1 - Alignment apparatus and alignment method - Google Patents

Abstract

Improve the accuracy of the alignment device. A first stage that holds one of a pair of substrates facing each other; a second stage that holds the other of the pair of substrates; and a first microscope that moves to observe an alignment mark of the substrate held on the second stage; The second microscope that moves to observe the alignment mark of the substrate held on the first stage, the first position information that indicates the position of the alignment mark observed by the second microscope, and the alignment mark that is observed by the first microscope An alignment control unit that aligns the pair of substrates held on the first stage and the second stage by moving at least one of the first stage and the second stage according to a difference from the second position information indicating the position. Is provided.

Description

The present invention relates to an alignment apparatus and an alignment method. This application is related to the following Japanese application and claims priority from the following Japanese application. For designated countries where incorporation by reference of documents is permitted, the contents described in the following application are incorporated into this application by reference and made a part of this application.
Japanese Patent Application No. 2008-256803 Application Date October 1, 2008

  There is a stacked semiconductor device in which substrates each having an element formed thereon are stacked (see Patent Document 1). The manufacturing process of the stacked semiconductor device includes a step of aligning and bonding a pair of substrates held in parallel with each other while individually observing with a plurality of microscopes (see Patent Document 2).

JP 11-261000 A JP 2005-251972 A

  The alignment in the manufacturing process of the stacked semiconductor device is required to be as accurate as the line width of the element on the substrate. For this reason, in addition to optical resolution, the microscope used for alignment is required to have high accuracy with respect to the position of the microscope itself.

  Therefore, in order to solve the above problems, as a first aspect of the present invention, a first stage that holds one of a pair of substrates facing each other, a second stage that holds the other of the pair of substrates, and a second stage A first microscope that moves to observe the alignment mark of the substrate held on the substrate, a second microscope that moves to observe the alignment mark of the substrate held on the first stage, and an alignment mark observed by the second microscope. According to the difference between the first position information indicating the position and the second position information indicating the position of the alignment mark observed with the first microscope, at least one of the first stage and the second stage is moved, An alignment apparatus is provided that includes an alignment control unit that aligns a pair of substrates held on a second stage.

  Further, as a second aspect of the present invention, a step of holding one of a pair of substrates facing each other on the first stage, a step of holding the other of the pair of substrates on the second stage, and a second stage are held. Observing the alignment mark of the substrate moved by moving the first microscope to detect second position information indicating the position of the alignment mark, and secondly aligning the alignment mark of the substrate held on the first stage. Observing by moving the microscope to detect first position information indicating the position of the alignment mark, and at least one of the first stage and the second stage according to the difference between the first position information and the second position information And aligning a pair of substrates held on the first stage and the second stage.

  The above summary of the invention does not enumerate all the features of the present invention. Further, a sub-combination of these feature groups can be an invention.

1 is a plan view schematically showing the structure of a multilayer substrate manufacturing system 100. FIG. It is a figure which shows typically the transition of the state of the board | substrate 180. FIG. It is a figure which shows typically the transition of the state of the board | substrate 180. FIG. It is a figure which shows typically the transition of the state of the board | substrate 180. FIG. It is a figure which shows typically the transition of the state of the board | substrate 180. FIG. It is a figure which shows typically the transition of the state of the board | substrate 180. FIG. It is a figure which shows the form of the alignment mark 184 typically. 3 is a cross-sectional view schematically showing the structure of the alignment unit 300. FIG. It is a figure which expands and shows a part of alignment part 300 shown in FIG. It is sectional drawing which shows the structure of the reference | standard label | marker 321. FIG. It is sectional drawing which shows the other structure of the reference | standard label | marker 321. FIG. 5 is a flowchart showing an alignment procedure in the alignment unit 300. FIG. 5 is a diagram showing the operation of the alignment unit 300 in contrast to FIG. 4. It is a figure which expands and shows a part of alignment part 300 of the state shown in FIG. FIG. 10 is a diagram illustrating the next operation of the alignment unit 300. It is a figure which shows the next operation | movement of the alignment part 300. FIG. It is a perspective view which shows the structure of the other alignment part 300. FIG. 4 is a plan view of an alignment unit 300. FIG. 6 is a side view showing the operation of the alignment unit 300. FIG. FIG. 11 is a side view showing another operation of the alignment unit 300. FIG. 11 is a side view showing still another operation of the alignment unit 300. FIG. 11 is a side view showing still another operation of the alignment unit 300.

  Hereinafter, the (1) aspect of the present invention will be described through embodiments of the invention. However, the following embodiments do not limit the invention according to the scope of claims, and the features described in the embodiments are as follows. Not all combinations are essential for the solution of the invention.

  FIG. 1 is a plan view schematically showing the overall structure of the multilayer substrate manufacturing system 100. The multilayer substrate manufacturing system 100 includes a normal temperature part 102 and a high temperature part 202 formed in a common housing 101.

  The normal temperature unit 102 has a plurality of substrate cassettes 111, 112, 113 and a control panel 120 facing the outside of the housing 101. The control panel 120 also includes a calibration control unit 122, an alignment control unit 124, and a control unit that controls the overall operation of the multilayer substrate manufacturing system 100. Furthermore, the control panel 120 has an operation unit that is operated by the user from the outside when the multilayer substrate manufacturing system 100 is turned on, various settings, and the like are performed.

  The substrate cassettes 111, 112, and 113 accommodate the substrates 180 bonded in the multilayer substrate manufacturing system 100 or the substrates 180 bonded in the multilayer substrate manufacturing system 100. The substrate cassettes 111, 112, and 113 are detachably attached to the housing 101. As a result, a plurality of substrates 180 can be loaded into the laminated substrate manufacturing system 100 at once. The substrates 180 bonded in the multilayer substrate manufacturing system 100 can be collected at once.

  The room temperature unit 102 includes a pre-aligner 130, an alignment unit 300, a substrate holder rack 160, and a pair of robot arms 171 and 172 inside the housing 101. The inside of the housing 101 is temperature-controlled so that a specific temperature substantially the same as the room temperature of the environment in which the multilayer substrate manufacturing system 100 is installed is maintained.

  Since the alignment unit 300 is highly accurate, the adjustment range is narrow. Therefore, the pre-aligner 130 temporarily aligns the positions of the individual substrates 180 so that the substrates 180 are within the narrow adjustment range. Thereby, the positioning in the alignment part 300 can be ensured.

  The alignment unit 300 includes an upper stage unit 310 and a lower stage unit 320 that face each other, and a pair of measurement units 330 that are arranged orthogonal to each other. In the alignment unit 300, the upper stage unit 310 and the lower stage unit 320 each transport the substrate 180 or the substrate holder 190 that holds the substrate 180. The measuring unit 330 measures the position of the moving upper stage unit 310 or the lower stage unit 320 in the surface direction of the substrate 180.

  A heat insulating wall 142 and a shutter 144 are provided so as to surround the alignment unit 300. The space surrounded by the heat insulating wall 142 and the shutter 144 is communicated with an air conditioner or the like, and the temperature is managed, so that the alignment accuracy in the alignment unit 300 is maintained. In the alignment unit 300, the pair of substrates 180 are aligned with each other. The detailed structure and operation of the alignment unit 300 will be described later with reference to FIG.

  The substrate holder rack 160 accommodates a plurality of substrate holders 190 and makes them stand by. The substrate holder 190 holds the substrates 180 one by one to facilitate handling of the substrates 180. The substrate holder 190 holds the substrate 180 by electrostatic adsorption, for example. The substrate holder rack 160 includes a substrate removal unit. The substrate removing unit takes out the substrate 180 sandwiched between the substrate holders 190 from the substrate holder 190 carried out from the pressurizing unit 240 described later.

  The substrate 180 loaded in the multilayer substrate manufacturing system 100 may be a single silicon wafer, compound semiconductor wafer, glass substrate, or the like, in which elements, circuits, terminals, and the like are formed. In some cases, the loaded substrate 180 is a laminated substrate formed by already laminating a plurality of wafers.

  Of the pair of robot arms 171, 172, the robot arm 171 disposed on the side closer to the substrate cassettes 111, 112, 113 transports the substrate 180 between the substrate cassettes 111, 112, 113, the pre-aligner 130, and the alignment unit 300. To do. The robot arm 171 also has a function of turning over one of the substrates 180 to be joined. Accordingly, the surfaces of the substrate 180 on which circuits, elements, terminals, and the like are formed can be opposed to each other.

  The robot arm 172 disposed on the side far from the substrate cassettes 111, 112, 113 carries the substrate 180 and the substrate holder 190 between the alignment unit 300, the substrate holder rack 160 and the air lock 220. Further, the robot arm 172 is also responsible for loading and unloading the substrate holder 190 with respect to the substrate holder rack 160.

  The high temperature unit 202 includes a heat insulating wall 210, an air lock 220, a robot arm 230, and a plurality of pressure units 240. The heat insulating wall 210 surrounds the high temperature part 202 to maintain a high internal temperature of the high temperature part 202 and to block heat radiation to the outside of the high temperature part 202. Thereby, the influence which the heat of the high temperature part 202 has on the normal temperature part 102 can be suppressed.

  The robot arm 230 conveys the substrate 180 and the substrate holder 190 between any of the pressurizing units 240 and the air lock 220. The air lock 220 includes shutters 222 and 224 that open and close alternately on the normal temperature part 102 side and the high temperature part 202 side.

  When the substrate 180 and the substrate holder 190 are carried into the high temperature unit 202 from the normal temperature unit 102, first, the shutter 222 on the normal temperature unit 102 side is opened, and the robot arm 172 carries the substrate 180 and the substrate holder 190 into the air lock 220. . Next, the shutter 222 on the normal temperature part 102 side is closed, and the shutter 224 on the high temperature part 202 side is opened.

  Subsequently, the robot arm 230 unloads the substrate 180 and the substrate holder 190 from the air lock 220 and loads them into one of the pressurizing units 240. The pressurizing unit 240 heats and pressurizes the substrate 180 carried into the pressurizing unit 240 while being sandwiched between the substrate holders 190. Thereby, the substrate 180 is permanently bonded.

  When the substrate 180 and the substrate holder 190 are carried out from the high temperature unit 202 to the normal temperature unit 102, the above series of operations are executed in reverse order. Through a series of these operations, the substrate 180 and the substrate holder 190 can be carried into or out of the high temperature part 202 without leaking the internal atmosphere of the high temperature part 202 to the normal temperature part 102 side.

  As described above, in many areas in the multilayer substrate manufacturing system 100, the substrate holder 190 is transferred to the robot arms 172 and 230, the upper stage unit 310, and the lower stage unit 320 while holding the substrate 180. When the substrate holder 190 holding the substrate 180 is transported, the robot arms 172 and 230 attract and hold the substrate holder 190 by vacuum suction, electrostatic suction or the like.

  2a, 2b, 2c, 2d, and 2e are diagrams schematically showing changes in the state of the substrate 180 in the multilayer substrate manufacturing system 100. FIG. As shown in FIG. 2a, at the beginning of the operation of the multilayer substrate manufacturing system 100, each of the substrates 180 is individually accommodated in one of the substrate cassettes 111 and 112, for example. The substrate holder 190 is also individually accommodated in the substrate holder rack 160.

  When the multilayer substrate manufacturing system 100 starts operation, the substrates 180 are carried one by one by the robot arm 171, pre-aligned by the pre-aligner 130, and then mounted on the substrate holder 190. Thus, the substrates 180 are each held by the substrate holder 190.

  Next, as shown in FIG. 2b, a pair of substrate holders 190 each holding the substrate 180 is prepared, and as shown in FIG. 2c, the substrate 180 is loaded into the alignment unit 300 so as to face each other. As shown in FIG. 2d, the substrate 180 and the substrate holder 190 aligned in the alignment unit 300 are connected and positioned by a plurality of fasteners 192 fitted in grooves 191 formed on the side surface of the substrate holder 190. Hold the state. The connected substrate 180 and substrate holder 190 are transported integrally and inserted into the pressure unit 240.

  By being heated and pressurized in the pressure unit 240, the substrates 180 are permanently bonded to each other to form a laminated substrate. Thereafter, the substrate 180 and the substrate holder 190 are unloaded from the pressure unit 240 and separated at the substrate removal unit of the substrate holder rack 160.

  The substrate 180 taken out from the substrate holder 190 is accommodated in, for example, the substrate cassette 113 by the robot arms 172 and 171 and the upper stage unit 310 and the lower stage unit 320. The substrate holder 190 from which the substrate 180 has been taken out is returned to the substrate holder rack 160 and stands by.

  FIG. 3 is a plan view schematically showing the form of the substrate 180 as a material of the laminated substrate. As illustrated, a plurality of element regions 186 are formed on the substrate 180, and alignment marks 184 are disposed in the vicinity of each of the element regions 186. Further, the substrate 180 has a notch 182 formed at a specific portion of the edge. The notches 182 are arranged corresponding to the crystal orientation of the substrate 180 and the like, and show the physical properties and the anisotropy of the arrangement in the substrate 180 having a substantially circular shape as a whole.

  The alignment mark 184 is used as an index when the element region 186 is formed on the substrate 180. For this reason, the position of the alignment mark 184 is closely related to the position of the element region 186 displaced by the deformation of the substrate 180 or the like. Therefore, when the substrates 180 are stacked, the distortion generated in each substrate 180 can be effectively compensated by using the alignment mark 184 as an alignment index.

  In the drawing, the element regions 186 and the alignment marks 184 are drawn large, but the number of element regions 186 formed on a large substrate 180 such as 300 mmφ is several hundred or more. Accordingly, the number of alignment marks 184 arranged on the substrate 180 also increases. Furthermore, the alignment mark 184 can be substituted by wiring, bumps, scribe lines, etc. formed on the substrate 180.

  FIG. 4 is a cross-sectional view schematically showing the structure of the alignment unit 300. The alignment unit 300 includes an upper stage unit 310 and a lower stage unit 320 disposed inside the frame body 301. In FIG. 4, one measurement unit 330 is also visible. The measurement unit 330 includes interferometers 332 and 334 having different heights.

  The frame 301 includes a top plate 302 and a bottom plate 306 that are parallel to each other and a plurality of columns 304 that couple the top plate 302 and the bottom plate 306. The top plate 302, the support column 304, and the bottom plate 306 are each formed of a highly rigid material, and are not deformed even when a reaction force related to the operation of the internal mechanism is applied.

  The upper stage unit 310 includes a drive unit 350, a substage 314, a spacer 311, and a main stage 312 that are sequentially suspended from the lower surface of the top plate 302. The substage 314 suspends the upper reflecting mirror 316 and the upper microscope 318. The main stage 312 sucks and holds the substrate holder 190 that holds the substrate 180.

  The drive unit 350 includes an X drive unit 351 and a Y drive unit 352 that move the substage 314 in the X direction and the Y direction indicated by arrows in the drawing, respectively. The substage 314 is integrally coupled to the main stage 312 via the spacer 311. Accordingly, the upper reflecting mirror 316 and the upper microscope 318 move in the X direction and the Y direction together with the substrate 180 while maintaining a certain relative position with respect to the substrate 180 held on the main stage 312.

  The lower stage unit 320 includes a drive unit 340, a substage 324, and a main stage 322 mounted on the upper surface of the bottom plate 306. The substage 324 includes a lower reflecting mirror 326 and a lower microscope 328. The main stage 322 sucks and holds the substrate holder 190 that holds the substrate 180. Further, a reference mark 321 is also mounted on the main stage 322.

  In the lower stage unit 320, the lower microscope 328 is mounted on the substage 324 via the vertical actuator 329. As a result, the lower microscope 328 moves up and down with respect to the substage 324 only in the vertical direction.

  The drive unit 340 includes an X drive unit 341, a Y drive unit 342, and a Z drive unit 348 that move the substage 324 in the X direction, the Y direction, and the Z direction indicated by arrows in the drawing. Further, a θ drive unit 344 that rotates the substage 324 in a horizontal plane and a φ drive unit 346 that swings the substage 324 are included. Note that the Z drive unit 348 is disposed between the substage 324 and the main stage 322, and also has a function corresponding to the spacer 311 in the upper stage unit 310.

  The substage 324 is integrally coupled to the main stage 322 by the Z drive unit 348. Accordingly, the lower reflecting mirror 326 and the lower microscope 328 rotate and swing together with the substrate 180 while maintaining a certain relative position with respect to the substrate 180 held on the main stage 322, and in the X direction and Y direction. Move in the direction and Z direction.

  Measurement unit 330 includes a pair of interferometers 332 and 334. One interferometer 332 is disposed at the same height as the reflecting mirror 316 of the upper stage unit 310. Thereby, the interferometer 332 uses the reflecting mirror 316 to accurately measure the position of the substage 314 in the X direction. Note that the measurement unit 330 that does not appear in this figure has the same structure, and measures the position of the substage 314 in the Y direction.

  The other interferometer 334 is disposed at the same height as the reflecting mirror 326 of the lower stage unit 320. Thereby, the interferometer 334 accurately measures the position of the substage 324 in the X direction using the reflecting mirror 326. The measurement unit 330 that does not appear in this figure also has the same structure, and measures the position of the substage 324 in the Y direction.

  FIG. 5 is an enlarged view showing the vicinity of the reference mark 321 in a state where the upper stage unit 310 and the lower stage unit are moved to a position where the reference mark 321 can be observed from the upper microscope 318. As shown in the drawing, the reference marker 321 can be put into the field of view from the upper microscope 318 by appropriately moving the upper stage portion 310 and the lower stage portion 320 as shown in the drawing.

  The reference mark 321 is disposed on a through hole 323 formed in the main stage 322 immediately above the lower microscope 328. As a result, the reference mark 321 also enters the field of view of the lower microscope 328.

  Further, the height of the reference mark 321 is adjusted to be the same height as the surface of the substrate 180 mounted on the main stage 322 of the lower stage unit 320. In the state shown in FIG. 5, the lower microscope 328 is lowered by the vertical actuator 329 and is focused on the reference mark 321. The upper microscope 318 observes the substrate 180 mounted on the lower stage unit 320, as will be described later. Therefore, in the above state, both the upper microscope 318 and the lower microscope 328 are in a state of focusing on the same reference mark 321.

  FIG. 6 is a cross-sectional view showing the structure of the reference mark 321 described above. The reference mark 321 includes a support frame 421, a transparent substrate 422, and an opaque thin film 423.

  More specifically, the transparent substrate 422 can be formed using a glass substrate or the like. An example of the opaque thin film 423 is a metal film. By thinning the opaque thin film 423, the observed position does not shift both when observed from the upper microscope 318 and when observed from the lower microscope 328. Note that the effective height of the reference mark 321 can be finely adjusted by adopting a structure in which the transparent substrate 422 is mounted on the main stage 322 via the support frame 421.

  The reference mark 321 has a transparent area where the transparent substrate 422 is exposed. Thus, the alignment mark 184 and the like positioned therethrough can be observed through the reference mark 321, which will be described later with reference to FIG.

  FIG. 7 is a cross-sectional view showing another structure of the reference mark 321. This reference mark 321 is formed by an opaque substrate 425 having a knife edge 427. The knife edge 427 is formed by a pair of surfaces intersecting with a line connecting the upper microscope 318 and the lower microscope 328.

  Such an opaque substrate 425 can be manufactured, for example, by processing a silicon wafer by dry etching. Since the tip of the knife edge 427 is very thin, the observed position does not shift both when observed from the upper microscope 318 and when observed from the lower microscope 328. Since the inside of the knife edge 427 penetrates, the lower microscope 328 can also observe the other side of the reference mark 321.

  FIG. 8 is a flowchart showing a procedure when the substrate 180 is aligned using the alignment unit 300 as described above. First, as shown in FIG. 4, the upper stage unit 310 and the lower stage unit 320 are opened so that the lower side of the main stage 312 of the upper stage unit 310 and the upper side of the main stage 322 of the lower stage unit 320 are opened. Shifting to different positions, the substrate 180 held by the substrate holder 190 is loaded on each of the main stages 312, 322 (step S101).

  Next, while observing the substrate 180 with a microscope (not shown) or the like, the φ driving unit 346 of the lower stage unit 320 is operated to make the pair of substrates 180 parallel (step S102). Hereinafter, the substrate 180 is aligned exclusively in the X direction and the Y direction.

  Subsequently, as shown in FIGS. 4 and 5, the reference marker 321 is simultaneously observed by the lower microscope 328 and the upper microscope 318, thereby specifying the relative positions of the lower microscope 328 and the upper microscope 318 (step S103). In this state, the calibration control unit 122 measures the positions of the upper stage unit 310 and the lower stage unit 320, and initializes the interferometers 332 and 334 using the measured values as initial values (step S104).

  Subsequently, the upper stage unit 310 and the lower stage unit are operated, and the alignment mark 184 of the substrate 180 held on the lower stage unit 320 is aligned with the alignment mark 184 of the substrate 180 held on the lower stage unit 320 by the upper microscope 318. Are detected three or more by the lower microscope 328 (step S105).

  FIG. 9 is a diagram showing the state of the alignment unit 300 that executes step S105 in contrast to FIG. As illustrated, the surface of the substrate 180 held by the lower stage unit 320 is brought into the field of view of the upper microscope 318 by operating the driving unit 350 of the upper stage unit 310 and the driving unit 340 of the lower stage unit 320, respectively. The surface of the substrate 180 held on the upper stage unit 310 can be put into the field of view of the lower microscope 328, respectively.

  FIG. 10 is an enlarged view showing the vicinity of the lower microscope 328 in the state shown in FIG. As shown in the drawing, the focus of the lower microscope 328 is moved to the surface of the substrate 180 held by the upper stage unit 310 by operating the vertical actuator 329. Accordingly, the lower microscope 328 can accurately observe the surface of the substrate 180 held on the upper stage unit 310 through the reference mark 321.

  Although not shown, the alignment unit 300 includes a low-power microscope for observing a wide range of the surface of the substrate 180 separately from the upper microscope 318 and the lower microscope 328. The resolution of the low-magnification microscope is less than the alignment accuracy of the substrate 180, but the approximate positions of the alignment mark 184 and the element region 186 on the substrate 180 can be recognized. By using such a low-magnification microscope in combination, the upper microscope 318 and the lower microscope 328 can efficiently detect the alignment mark 184.

  Returning to the procedure shown in FIG. 8 again, when the upper microscope 318 and the lower microscope 328 detect the alignment mark 184 of the opposing substrate 180, the positions of the main stages 312 and 322 at that time are interferometers 332 and 334, respectively. The relative position of the alignment mark 184 with respect to the initial value can be determined by measuring at The relative position of the detected alignment mark 184 is stored by the alignment control unit 124 (step S106).

  Thus, when the alignment control unit 124 acquires the position information of the three or more alignment marks 184 for each of the pair of substrates 180, the drive unit required when aligning the substrate 180 based on the position information. The movement amounts of 340 and 350 can be calculated (step S107).

  In other words, the substrate 180 used for bonding is formed with elements and the like through a lot of processing and processing. For this reason, various distortions are generated in the substrate 180. Further, the strain distribution on one substrate 180 is not uniform. For this reason, when aligning the substrates 180, even if the positions of the specific alignment marks 184 corresponding to the pair of substrates 180 are matched, misalignment may increase in other portions of the substrate 180.

  However, as for the relative position information of each of the three or more alignment marks 184 corresponding to each other between the pair of substrates 180, the error between the corresponding alignment marks is statistically reduced between the plurality of alignment marks as follows. By executing such processing, the positional deviation of the alignment mark 184 that occurs in the entire substrate 180 can be minimized.

Hereinafter, the alignment method will be described. In a pair of wafers, a translation amount (T _x , T _y ) that one of the wafers should translate relative to the other and a rotation amount θ that should be rotated are calculated as follows. The following relationship exists between the position coordinates (A _xi , A _yi ) of the measured alignment mark with respect to the reference coordinate system and the converted position coordinates (M _xi , M _yi ). “I” indicates the number of the alignment mark.

Next, assuming that the position coordinate of one substrate 180 with respect to the reference coordinate system is (D _xi , D _yi ), the movement amount (T _x , T _y ) of the other substrate 180 and the following function F are _minimized. The rotation amount θ is determined.

FIG. 11 is a diagram illustrating the next operation of the alignment unit 300. As illustrated, the alignment control unit 124 uses the initial values based on the relative positions of the upper microscope 318 and the lower microscope 328 as a reference, and the driving unit 340 according to the calculated movement amount (T _x , T _y ) and the rotation amount θ. , 350 can be operated to align the pair of substrates 180 (step S108).

  In order to further improve the alignment accuracy, a plurality of reference markers 321 may be provided and the step of calibrating the relative positions of the upper microscopes 318 and 328 (step S104) may be executed several times. In particular, when the upper stage unit 310 or the lower stage unit 320 moves greatly, when the operation direction is switched to the X direction or the Y direction, the procedure from the stage 104 may be repeated.

  FIG. 12 is a diagram showing the alignment unit 300 and the next operation. As illustrated, the Z driving unit 348 can be operated to bond the substrates 180 that are aligned in the X direction and the Y direction and face each other. That is, the substrate 180 can be temporarily joined by raising the main stage 322 of the lower stage unit 320 to contact the pair of substrates 180 and further increasing the driving force of the Z driving unit 348 (step S109). .

  The pair of substrates 180 that have been aligned and bonded in this way are unloaded from the alignment unit 300 (step S110) and transferred to the pressurizing unit 240, as already described. While being conveyed from the alignment unit 300 to the pressurizing unit 240, as described with reference to FIG. 2b, the aligned state is held by the substrate holder 190 and the fastener 192.

  In the above example, the upper stage unit 310 and the lower stage unit 320 both have the driving units 350 and 340 to move the main stages 312 and 322. In this case, it is also preferable to distribute the operation amounts of the drive units 350 and 340 so that the movement amounts of both the upper stage unit 310 and the lower stage unit 320 are equal. As a result, the wear of the members can be made uniform, and the life of the device can be extended.

  The alignment of the substrate 180 can be performed even when either the upper stage part 310 or the lower stage part 320, for example, the drive part 350 of the upper stage part 310 is omitted and the main stage 312 is fixed. For example, the Y driving unit 352 of the upper stage unit 310 may be omitted, and the upper stage unit 310 may be aligned exclusively in the X direction, and the lower stage unit 320 may be aligned exclusively in the Y direction.

  However, by moving both the main stages 312, 322, the time required to move the required amount of movement can be reduced by half. Therefore, by providing the drive units 350 and 340 in both the upper stage unit 310 and the lower stage unit 320, the throughput in the alignment unit 300 can be improved.

  In the above example, the reference mark 321 is fixed and the lower microscope 328 is moved up and down. However, in addition to a structure in which the lower microscope 328 is fixed and the focal length is optically changed, various modifications can be made such as a structure in which the reference marker is advanced and retracted from the field of view of the upper microscope 318 or the lower microscope 328. Furthermore, it is also possible to employ a structure in which the measurement of each alignment mark 184 of the substrate 180 and the alignment of the pair of substrates 180 are performed by separate facilities.

  FIG. 13 is a perspective view showing an alignment unit 300 having another structure. The alignment unit 300 includes a measurement unit 360, a pair of microscope units 370, and a joint unit 380 mounted on the bottom plate 303. Further, although not shown in FIG. 13 for the purpose of avoiding complicated drawing, a robot arm 390 is disposed between the measurement unit 360 and the joint unit 380 (see FIG. 14).

  The measurement unit 360 is formed inside a rectangular frame formed by a pair of support columns 361 standing upright from the bottom plate 303 and a pair of horizontal guide units 363 that respectively connect the upper end and the lower end of the support column 361. Each of the guide units 363 suspends or supports the X drive unit 362, the Z drive unit 364, and the main stages 312, 322, respectively.

  In the measurement unit 360, the X drive unit 362 individually connects the Z drive unit 364 and the main stages 312 and 322, and the substrate holder 190 and the substrate 180 mounted on the main stages 312 and 322 along the guide unit 363. Move. The Z drive unit 364 moves the main stages 312 and 322 and the substrate holder 190 and the substrate 180 mounted on the main stages 312 and 322 vertically up and down.

  A substrate holder 190 holding the substrate 180 is mounted on each of the main stages 312 and 322. Each of the substrates 180 has a pair of alignment marks 184.

  Further, a reference mark 321 is also mounted on one main stage 322. The reference mark 321 is fixed at the same height as the surface of the substrate 180 held by the substrate holder 190. Since the main stage 322 has a through hole penetrating in the thickness direction under the reference mark 321, the reference mark 321 can be observed from above and below the main stage 322. Note that the reference mark 321 may adopt any of the structures shown in FIGS.

  The pair of microscope units 370 are arranged with the measurement unit 360 interposed therebetween. Each of the microscope units 370 includes a Y driving unit 372, a support column 374, and microscopes 376 and 378. The Y drive unit 372 moves the support column 374 in a direction intersecting with the extending direction of the guide unit 363 of the measurement unit 360. The support columns 374 support a pair of microscopes 376 and 378, respectively.

  That is, the pair of microscopes 376 and 378 are fixed to be opposed to each other vertically inside the notch formed in the middle of the support column 374. The focal points F of the microscopes 376 and 378 are connected to a common point located in the middle of the microscopes 376 and 378.

  On the other hand, the joint portion 380 includes an X drive portion 381, a Y drive portion 382, a θ drive portion 384, a Z drive portion 388, a pair of flat plates 389, and a pair of main stages, which are arranged in the stacking direction inside the frame 383. 312 and 322. Each of the main stages 312 and 322 carries a substrate holder 190 that holds a substrate 180.

  The X drive unit 381 and the Y drive unit 382 drive the main stages 312 and 322 in the X direction or the Y direction indicated by arrows in the drawing. The Z drive unit 388 can move the main stage 312 in the Z-axis direction, and can also swing the main stage 322 by individually operating.

  The bonding unit 380 is mounted on the main stage 312 by moving the substrate 180 mounted on the main stage 322 in an arbitrary direction by operating the X driving unit 381, the Y driving unit 382, and the θ driving unit 384. Alignment with respect to the substrate 180 is possible. By operating the Z driving unit 388, the pair of substrates 180 aligned with each other can be brought into contact with each other and bonded.

  FIG. 14 is a plan view of the alignment unit 300 shown in FIG. As illustrated, the alignment unit 300 further includes a robot arm 390 between the measurement unit 360 and the joint unit 380.

  The robot arm 390 has a fork portion 392 and an arm portion 394. The fork unit 392 sucks and holds the substrate holder 190 that holds the substrate 180. The arm part 394 moves the fork part 392 holding the substrate holder 190 in an arbitrary direction. Thus, the robot arm 390 transports the substrate 180 and the substrate holder 190, which have been measured later in the measurement unit 360, from the main stages 312 and 322 of the measurement unit 360 to the main stages 312 and 322 of the joint unit 380. Can be transferred.

  Depending on the layout of the multilayer substrate manufacturing system 100, a robot arm 172 that carries the substrate 180 and the substrate holder 190 into and out of the alignment unit 300 may be used. In this case, the robot arm 390 of the alignment unit 300 can be omitted.

  FIGS. 15a, 15b, 15c, and 15d are diagrams illustrating the operation of the measurement unit 360 in the alignment unit 300 having the above-described structure. As shown in the figure, the alignment unit 300 is arranged on the side surfaces of the main stages 312 and 322 facing the interferometers 366 and 368 and the interferometers 366 and 368 which are hidden in the support column 361 in FIGS. It further includes a pair of reflecting mirrors 367 mounted. The operation of these interferometers 366 and 368 and the reflecting mirror 367 will be described later.

  First, as shown in FIG. 15 a, the X driving unit 362 is operated, and the main stages 312 and 322 are moved to positions close to different columns 361. Thereby, the lower surface of the main stage 312 and the upper surface of the main stage 322 are opened. In this state, a substrate holder 190 holding the substrate 180 is mounted on each of the main stages 312 and 322.

  Next, as shown in FIG. 15 b, under the control of the calibration control unit 122, the Z drive unit 364 of the lower main stage 322 is operated to raise the main stage 322. Thereby, the reference mark mounted on the main stage 322 becomes the same height as the focal point F of the microscopes 376 and 378.

  Subsequently, the X drive unit 362 is operated to move the main stage 322 to a position where the reference mark 321 enters the field of view of the microscopes 376 and 378. In this state, by observing the common reference mark 321 with the pair of microscopes 376 and 378, the calibration control unit 122 can accurately detect the positions of the pair of microscopes 376 and 378.

  Note that the microscopes 376 and 378 are fixed to the column 374, respectively, but their positions may change depending on environmental conditions such as temperature, inclination of the column 374 due to tolerance of the Y driving unit 372, and the like. However, as described above, the positional relationship between the microscopes 376 and 378 can be grasped by observing the common reference mark 321 prior to measuring the position of the alignment mark 184.

  Next, as shown in FIG. 15 c, the X driving unit 362 is further operated to move the main stage 322, and the alignment mark 184 of the substrate 180 is placed in the field of view of the upper microscope 376. Since the reference mark 321 and the surface of the substrate 180 are located at the same height, the surface of the substrate 180 passes through the focal plane of the upper microscope 376.

  Further, while the main stage 322 moves, the moving amount of the main stage 322 is accurately measured using the reflecting mirror 367 and one interferometer 368. Thereby, the position of the alignment mark 184 on the substrate 180 can be measured with reference to the position of the microscope 378 configured in the reference mark 321. The measured position information of the alignment mark 184 is stored in the alignment control unit 124.

  Subsequently, as shown in FIG. 15d, the lower main stage 322 is returned to the original position, while the upper main stage 312 is moved. That is, first, the Z driving unit 364 is operated to move the surface of the substrate 180 to the same height as the focal point F of the microscopes 376 and 378. Subsequently, the X driving unit 362 is operated to move the substrate 180 between the pair of microscopes 376 and 378.

  At this time, the amount of movement of the main stage 312 can be accurately measured using the reflecting mirror 367 and the interferometer 366 provided on the upper main stage 312 side. Therefore, the position of the alignment mark 184 on the substrate 180 can be accurately detected by observing with the lower microscope 378. The measured position information of the alignment mark 184 is stored in the alignment control unit 124.

  Thus, when the alignment control unit 124 acquires the position information of the alignment mark 184 for each of the pair of substrates 180, the substrate holder 190 that holds the substrate 180 is moved by the robot arm 390 to the main stages 312 and 322 of the bonding unit 380. Respectively. On the other hand, the alignment control unit 124 calculates an operation amount of the bonding unit 380 obtained when the substrate 180 is aligned based on the position information.

  First, the bonding unit 380 in which the substrate holder 190 holding the substrate 180 is inserted operates the Z driving unit 388 individually to make the pair of substrates 180 parallel to each other. Subsequently, the X driving unit 381, the Y driving unit 382, and the θ driving unit 384 are operated based on an instruction from the alignment control unit 124, and the pair of substrates 180 are moved so that the positions of the corresponding alignment marks 184 coincide with each other. Align. Further, the Z driving unit 388 is operated simultaneously to bring the pair of substrates 180 into contact with each other, and by applying a higher pressure, the pair of substrates 180 is joined.

  Note that the alignment unit 300 in this aspect includes a measurement unit 360 and a bonding unit 380, and individually performs the position measurement of the alignment mark 184 and the bonding of the substrate 180. With such a structure, in the measurement unit 360, the X drive unit 362 and the Z drive unit 364 can be downsized, and the movement range of the microscopes 376 and 378 can be expanded. In addition, in the bonding portion 380, it is possible to execute accurate alignment and bonding of the substrates 180 with high pressure using a large member having high strength. However, if the strength of the member can be ensured, it is possible to add the Y drive unit 382, the θ drive unit 384, and the like to the structure of the measurement unit 360 and execute the alignment and joining.

  In the embodiment shown in FIGS. 1 to 15d, a microscope for observing the substrate 180 held on the upper stage portion 310 or the like is disposed on the lower stage portion 320 or the like facing the substrate 180, and the substrate 180 held on the lower stage portion 320 or the like. The microscope to be observed is disposed on the upper stage unit 310 or the like facing the microscope. However, the arrangement of the microscope is not limited to this. A microscope for observing the substrate 180 held on the upper stage unit 310 or the like is arranged on the same upper stage unit 310 or the like, and a microscope for observing the substrate 180 held on the lower stage unit 320 or the like is arranged on the same lower stage unit 320 or the like May be. In this case, the microscope lens arranged on the upper stage unit 310 is arranged to face upward, and the microscope lens arranged on the lower stage unit 320 is arranged to face downward.

  In the embodiment shown in FIGS. 1 to 15d, the upper stage unit 310 and the lower stage unit 320 are movable, but one of them may be fixed and the other may be movable. Further, the microscope may be movable independently with respect to the upper stage unit 310 and the lower stage unit 320. In this case, the space required for the movement of the upper stage part 310 and the lower stage part 320 can be saved by moving the microscope while stopping the upper stage part 310 and the lower stage part 320 when the alignment mark 184 is observed.

  As mentioned above, although this invention was demonstrated using embodiment, the technical scope of this invention is not limited to the range as described in the said embodiment. It will be apparent to those skilled in the art that various modifications or improvements can be added to the above embodiment. Further, it is apparent from the scope of the claims that the embodiments added with such changes or improvements can be included in the technical scope of the present invention.

  The execution order of each process such as operations, procedures, steps, and stages in the apparatus, system, program, and method shown in the claims, the description, and the drawings is particularly “before” or “prior”. It should be noted that they can be implemented in any order unless the output of the previous process is used in the subsequent process. Regarding the operation flow in the claims, the description, and the drawings, even if it is described using “first”, “next”, etc. for the sake of convenience, it means that it is essential to carry out in this order. is not.

100 laminated substrate manufacturing system, 101 housing, 102 room temperature section, 111, 112, 113 substrate cassette, 120 control panel, 122 calibration control section, 124 alignment control section, 130 pre-aligner, 142, 210 heat insulation wall, 144, 222, 224 Shutter, 160 Substrate holder rack, 171, 172, 230, 390 Robot arm, 180 Substrate, 182 Notch, 184 Alignment mark, 186 Element area, 190 Substrate holder, 191 Groove, 192 Fastener, 202 High temperature part, 220 Air lock , 240 Pressure unit, 300 Alignment unit, 301 Frame body, 302 Top plate, 303 Bottom plate, 304, 374 Column, 306 Bottom plate, 310 Upper stage unit, 311 Spacer, 312, 322 Main stage, 314, 324 Sub Stage, 316, 326, 367 Reflector, 318, 328, 376, 378 Microscope, 320 Lower stage, 321 Reference mark, 323 Through hole, 329 Vertical actuator, 330 Measuring unit, 332, 334, 366, 368 Interferometer, 340, 350 drive unit, 341, 351, 362, 381 X drive unit, 342, 352, 372, 382 Y drive unit, 344, 384 θ drive unit, 346 φ drive unit, 348, 364, 388 Z drive unit, 360 Measurement unit, 361 support column, 363 guide unit, 370 microscope unit, 380 joint unit, 383 frame, 389 flat plate, 392 fork unit, 394 arm unit, 421 support frame, 422 transparent substrate, 423 opaque thin film, 425 opaque substrate, 427 knife Edge

Claims (11)

A first stage for holding one of a pair of substrates facing each other;
A second stage for holding the other of the pair of substrates;
A first microscope that moves to observe the alignment marks of the substrate held on the second stage;
A second microscope that moves to observe the alignment marks of the substrate held on the first stage;
The first stage and the second stage according to the difference between the first position information indicating the position of the alignment mark observed with the second microscope and the second position information indicating the position of the alignment mark observed with the first microscope. An alignment apparatus comprising: an alignment control unit configured to align a pair of substrates held on the first stage and the second stage by moving at least one of the stages.   The alignment apparatus according to claim 1, wherein the alignment control unit moves the first stage and the second stage with an equal movement amount.   The alignment apparatus according to claim 1, wherein the alignment control unit moves the first stage and the second stage in different directions. A calibration marker commonly observed from the first microscope and the second microscope;
The alignment apparatus according to claim 1, further comprising: a calibration control unit that causes the first microscope and the second microscope to observe the calibration mark and calibrates the relative positions of the first microscope and the second microscope.   The alignment apparatus according to claim 4, wherein the calibration control unit moves the first stage and the second stage with an equal movement amount.   The alignment according to claim 4, wherein the calibration control unit observes the calibration marker that has entered the field of view of the first microscope with the second microscope, and detects a relative position between the first microscope and the second microscope. apparatus. The calibration marker is disposed on one focal plane of the first microscope and the second microscope;
The alignment apparatus according to claim 4, wherein the calibration control unit moves the other of the first microscope and the second microscope to focus the microscope on the calibration mark.   5. The alignment apparatus according to claim 4, wherein either the first microscope or the second microscope observes an alignment mark of a substrate held on either the second stage or the first stage through the calibration mark.   The alignment apparatus according to claim 1, wherein the first microscope moves together with the first stage, and the second microscope moves together with the second stage. The first microscope observes a plurality of alignment marks on the substrate held on the second stage,
The second microscope observes a plurality of alignment marks corresponding to the plurality of alignment marks of the substrate held on the second stage in the substrate held on the first stage,
The alignment control unit includes the first stage and the first stage so that an error between the corresponding alignment marks observed with the first microscope and the second microscope is statistically small between the plurality of alignment marks. The alignment apparatus according to claim 1, wherein the second stage is moved. Holding one of a pair of opposing substrates on a first stage;
Holding the other of the pair of substrates on a second stage;
Observing the alignment mark of the substrate held on the second stage by moving the first microscope, and detecting second position information indicating the position of the alignment mark;
Observing the alignment mark of the substrate held on the first stage by moving the second microscope to detect first position information indicating the position of the alignment mark;
A pair of substrates held on the first stage and the second stage is moved by moving at least one of the first stage and the second stage according to a difference between the first position information and the second position information. An alignment method comprising:

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