TW202127512A - Substrate bonding device and method - Google Patents

Abstract

This substrate bonding device comprises: a pair of electrodes 351a disposed with at least one of substrates 211, 213 interposed therebetween; and a detection unit 353a that detects an electrostatic characteristic between the two electrodes included in the pair of electrodes. When a contact region is formed by bringing parts of the respective substrates between the substrates and the contact region expands in the planar direction, the detection unit can detect the state of the contact region, that is, a bonding process of the substrates, by detecting the electrostatic characteristic between the two electrodes included in the pair of electrodes 351a that are disposed with at least one of the substrates 211, 213 interposed therebetween.

Description

Substrate bonding device and method

The present invention relates to a substrate bonding device and method.

In the manufacture of electronic devices such as semiconductor devices, the surface of two substrates is activated, and a part of the activated surfaces is contacted to form a contact area, and the contact area is aligned along the direction of the bonding surface. The technology of laminating two substrates in an enlarged way. At this time, the progress of the bonding will vary depending on the state of the substrate, etc., so a technology for detecting the progress of the bonding will be required. Therefore, Patent Document 1 discloses the use of a plurality of light-receiving parts arranged in a line from the position of the contact area under a head-up view to receive reflected light from the other through one of the two substrates to be bonded to detect the progress state of the bonding Device. However, it is necessary to arrange a plurality of light-receiving parts in the holder holding the substrate or the holder holding the holder, which is not suitable. [Patent Document 1] JP 2012-191037 A

The first aspect of the present invention provides a substrate bonding device which is a substrate bonding device for bonding a first substrate and a second substrate, and includes a pair of electrodes that sandwich at least one of the first substrate and the second substrate. Configuration; and the detection part, which detects the electrostatic characteristics between a pair of electrodes.

The second aspect of the present invention provides a substrate bonding method, which is a substrate bonding method for bonding a first substrate and a second substrate, including: forming a contact between the first substrate and the second substrate in contact with each other. The stage of the area; the stage of expanding the contact area; and the stage of detecting the electrostatic characteristics between a pair of electrodes arranged sandwiching at least one of the first substrate and the second substrate.

In addition, the content of the above invention does not enumerate all the features of the present invention. In addition, sub-combinations of these feature groups can also become inventions.

Hereinafter, the present invention will be explained through embodiments of the invention. However, the following embodiments are not intended to limit the scope of the patent application of the inventor. In addition, it is not limited to that all combinations of the features described in the embodiments are necessary for the means of solving the invention.

FIG. 1 schematically shows the structure of the substrate bonding system 100. The substrate bonding system 100 is an apparatus group for bonding two substrates to form a multilayer device, and includes: a frame 110, a conveying device 140, a control device 150, a bonding device 300, a holder temporary storage box 400, and pre-alignment器500. In addition, the bonded substrate 210 is accommodated in the substrate cassette 120, and the bonded substrate (also referred to as a bonded substrate) 230 is accommodated in the substrate cassette 130.

The frame 110 accommodates the conveying device 140, the laminating device 300, the holder temporary storage box 400, and the pre-aligner 500 inside. The inside of the frame 110 is subjected to temperature management, for example, kept at room temperature. The substrate cassettes 120 and 130 can be individually detachably fixed from the outer side of the frame 110. A plurality of substrates 210 can be carried into the substrate bonding system 100 together by the substrate cassette 120, and the plurality of bonded substrates 230 after being bonded can be carried out from the substrate bonding system 100 by the substrate cassette 130 together.

The conveying device 140 is a device that holds the substrates 210 and 230 by telescopic arms, and conveys the substrates 210 and 230 between the substrate cassettes 120 and 130 and the respective devices in the frame 110. The conveying device 140 conveys the individual substrate 210, the holder 220, the holder 220 holding the substrate 210, the substrate 230 laminated with the substrate 210 and the like.

The control device 150 is a device that connects the various devices of the substrate bonding system 100 to each other to control the overall control. The control device 150 receives instructions from an external user and sets the manufacturing conditions when manufacturing the bonded substrate 230. Furthermore, the control device 150 has a user interface that displays the operating state of the substrate bonding system 100 toward the outside.

The bonding apparatus 300 forms a part of the contact area between the two substrates 210 in contact with each other, so that the contact area expands in the direction along the bonding surface (also referred to as the surface direction) to directly bond 2 Two substrates form a device for bonding the substrate 230. In addition, there may be cases where the contact area of the substrates 211 and 213 is enlarged and the boundary advances in the surface direction, which appears as the progress of the bonding wave. Here, the term “bonding” includes the state in which the terminals respectively provided on the two substrates 210 are electrically connected between the substrates 210; and the insulating films formed on the surfaces of the two substrates 210 are joined to each other and the substrates 210 are not connected to each other. The state of electrical connection includes both the separable and inseparable states of the two substrates 210 in any state. In order to improve the bonding strength of the two substrates 210, it is preferable to carry the substrate 210 into a heating device such as an annealing furnace for heating after bonding the two substrates 210. The structure and operation of the bonding device 300 will be described later.

The holder temporary storage box 400 contains a plurality of holders 220. The holder 220 is formed of a hard material such as alumina ceramics, and has: a holding part for adsorbing the substrate 210; and an edge part arranged on the outside of the holding part. Inside the substrate bonding system 100, the holder 220 sucks and holds the substrate 210 by the holding portion, and is processed integrally with the substrate 210. Thereby, when the suction surface of the holding portion is flat, flatness can be ensured on the substrate 210 that has been warped or deflected. After the substrate 210 is bonded, when the bonded substrate 230 is unloaded from the substrate bonding system 100, the holder 220 is separated from the bonded substrate 230, and is stored in the holder temporary storage box 400 again. In this way, a small number of holders 220 can be used repeatedly.

The pre-aligner 500 cooperates with the conveying device 140 to hold the holder 220 to carry the substrate 210 of the substrate bonding system 100. In addition, the pre-aligner 500 can also be used when separating the bonding substrate 230 carried out from the bonding device 300 from the holder 220.

In addition to the substrate 210 on which elements, circuits, terminals, etc. are formed, the substrate bonding system 100 may also bond unprocessed silicon wafers, compound semiconductor wafers, glass substrates, and the like. In addition, it is also possible to bond a circuit board on which a circuit is formed and an unprocessed board, or bond the same types of circuit boards to each other and unprocessed boards. Furthermore, the substrate 210 to be bonded may also be a bonded substrate 230 formed by laminating a plurality of substrates.

FIG. 2 shows the surface structure of the substrate 210 bonded by the substrate bonding system 100. The substrate 210 has a groove 214, a plurality of circuit regions 216, and a plurality of alignment marks 218.

The groove 214 is formed on the periphery of the substrate 210 which is generally circular as a whole and serves as an indicator for displaying the crystal orientation of the substrate 210. In addition, when processing the substrate 210, by detecting the position of the groove 214, the arrangement direction of the circuit area 216 in the substrate 210 can also be known. Furthermore, when one substrate 210 is formed with circuit regions 216 that are different from each other, the groove 214 can be used as a reference to distinguish the circuit regions 216.

The circuit area 216 is periodically arranged on the surface of the substrate 210 in the direction of the substrate 210. In each circuit region 216, a semiconductor device, wiring, protective film, etc. formed by photolithography technology or the like are provided. The circuit area 216 is also provided with pads, bumps, etc., which become connection terminals when the substrate 210 is electrically connected to other substrates 210, a lead frame, and the like.

The alignment mark 218 is arranged, for example, overlapping the scribe line 212 arranged between the circuit regions 216, and is used as an index when aligning the substrate 210 with another substrate 210, that is, a laminate target.

FIG. 3 schematically shows the structure of the bonding device 300. The substrates 211 and 213 are respectively held by the holders 221 and 223 and carried into the bonding apparatus 300. The bonding apparatus 300 includes a housing 310, a loading table 322, a downloading table 332, an interferometer 341, microscopes 324 and 334, activation devices 326 and 336, and a bonding detection device 350.

The frame 310 is a member that supports the constituent parts of the laminating device 300, and has a bottom plate 312 installed on a horizontal ground (not shown) via an anti-vibration device (not shown), and a plurality of pillars erected on the bottom plate 312 314. A top plate 316 supported by a plurality of pillars 314.

The upper stage 322 is a stage that supports the substrate 211, and is fixed to the top plate 316 of the frame 310 with the holding surface of the substrate 211 facing downward. Here, the substrate 211 is held by the holder 221, and is held on the holding surface by a vacuum chuck or an electrostatic chuck therethrough.

The download stage 332 is a stage that faces the substrate 211 held on the upper stage 322 and supports the substrate 213. The downloading table 332 has: an X-direction driving part 331 arranged on the bottom plate 312 of the frame 310; a Y-direction driving part 333 arranged on the X-direction driving part 331; Drive section 338; thereby, the download table 332 supporting the substrate 213 is driven in the XY direction, that is, in the horizontal direction and the Z axis direction, that is, in the vertical direction. Here, the substrate 213 is held by the holder 223, and is held by a vacuum chuck or an electrostatic chuck on the holding surface of the carrier through this.

Here, the X-direction driving unit 331 moves on the bottom plate 312 in the X-axis direction. The Y-direction drive unit 333 moves in the Y-axis direction on the X-direction drive unit 331. By combining the actions of these driving parts, the download table 332 is moved on the bottom plate 312 in the XY direction. In this way, the substrate 213 supported on the download table 332 can be aligned with the substrate 211 supported on the upper stage 322.

In addition, the raising/lowering drive portion 338 is raised and lowered in the Z-axis direction with respect to the Y-direction driving portion 333. The download platform 332 is supported on the lifting driving part 338. Thereby, the substrate 213 supported on the download station 332 can be pressed to the substrate 211 supported on the upper stage 322.

In addition, the X-direction drive portion 331 and the Y-direction drive portion 333 may be configured as a coarse movement portion and a fine movement portion. Thereby, by combining the high output of the coarse movement part and the high precision alignment by the fine movement part, the substrate 213 supported on the loading table 332 can be aligned with high precision and high speed.

In addition, a rotary drive unit that rotates the download platform 332 around the Z axis and a swing drive unit that swings the download platform 332 can be further provided. The substrate 213 held by the download table 332 is rotated by the rotation driving part, and the download table 332 is parallel to the upper stage 322 by the swing driving part, so that the alignment accuracy of the substrates 211 and 213 can be improved.

The interferometer 341 is a measuring instrument that measures the position of the loading platform 332, and is fixed to the pillar 314 on the left side of the frame 310 as an example. The interferometer 341 projects measurement light on the mirror surface provided on the side surface of the download table 332 (here, the Y-direction drive section 333), and detects the reflected light and the reference light (not shown). The measurement download table 332 is located at Position in the horizontal direction. The measurement result is supplied to the control device 150.

The microscope 324 is a detection system for detecting the alignment mark of the substrate 213 supported on the download table 332, and is fixed to the top plate 316 of the frame 310 facing downward. The detection result of the microscope 324 is supplied to the control device 150.

The microscope 334 is a detection system that detects the alignment mark of the substrate 211 supported on the upper stage 322, and is fixed to the upper left side of the download stage 332 (here, the Y-direction driving part 333) facing upward. The detection result of the microscope 334 is supplied to the control device 150.

The activation device 326 is a device that purifies the plasma on the substrate 213 held on the download table 332, and is fixed to the top plate 316 of the frame 310 facing downward.

The activation device 336 is a device that purifies the plasma on the surface of the substrate 211 supported on the upper stage 322, and is fixed to the upper left side of the download stage 332 (here, the Y-direction driving part 333) facing upward.

In addition, the position of the downloading station 332 or the relative position of the microscopes 324 and 334 can be driven by driving the downloading station 332 to position the microscope 334 directly under the microscope 324, and focus the microscopes 324 and 334 on each other or on the common index, so as to Reset the calibration by the method of measuring the coordinates set by the optical axis of the measuring light of the interferometer 341 (refer to FIG. 13A). The relative position of the microscopes 324 and 334 is also called the baseline, and the calibration of the relative position is also called the baseline measurement.

The bonding detection device 350 is a device that detects the bonding state of the substrates 211 and 213, and includes a plurality of electrodes 351, an electrode driving device 352, and a detection unit 353.

The plurality of electrodes 351 are electrodes for detecting the position of the substrate 211 in the Z-axis direction, and include at least a pair of electrodes that are arranged to sandwich the substrates 211 and 213 without contact in the surface direction of the substrates 211 and 213. Here, at least one of the electrode surfaces of the pair of electrodes facing each other has a shape whose width changes along the XY direction, that is, the surface direction, that is, along the Z-axis direction. In this embodiment, a circle is formed, but it is not limited to this, and it may also be an ellipse, triangle, rhombus, trapezoid, or the like. Thereby, by the substrate 211 moving in the Z-axis direction, the width or area S of the electrode portion opposite to the substrate 211 is changed, whereby the electrostatic capacitance between a pair of electrodes is a positive or negative correlation with the electrostatic capacitance. (These are collectively referred to as electrostatic characteristics) will change. Here, when the electrostatic capacitance C between the electrodes is assumed to be dominantly determined by the substrate 211, using the dielectric constant ε and the separation distance D of the pair of electrodes, it can be obtained as C=εS/D. The arrangement of the plurality of electrodes 351 will be further described later.

In addition, in the case of an electrode having a polygonal electrode surface such as a triangle, a rhombus, a trapezoid, etc., the relationship between the area S(Z) of the electrode portion facing the substrate 211 and the position Z of the substrate 211 in the Z-axis direction becomes linear, so The linearity of the electrostatic characteristic C between the electrodes with respect to the Z position of the substrate 211 can be obtained. In contrast, in the case of a circular electrode, the area S(Z) of the electrode portion facing the substrate 211 has a non-linear relationship with the Z position of the substrate 211. Therefore, the Z position and the area S(Z) can also be used. The relationship linearizes the relationship between the electrostatic characteristic C between the electrodes and the Z position.

In the example shown in the figure, the electrode driving device 352 is a device that moves a plurality of electrodes 351 to the sides of the substrates 211 and 213 and retreats from the sides of the substrates 211 and 213. The electrode driving device 352 is fixed to the side of the upper stage 322 by the top plate 316 of the frame 310, and drives a plurality of electrodes 351 in the Z-axis direction by, for example, an electromagnetic motor. The electrode driving device 352 retracts the plurality of electrodes 351 to a position where the substrate 211 does not contact the substrate 211 when the substrate 211 is loaded into the upper stage 322, and retracts the plurality of electrodes 351 to a position where the loading table 332 moves during detection of the alignment mark. Contact the position of the substrate 213.

In addition, the electrode driving device 352 can also move the two electrodes of the electrode pair included in the plurality of electrodes 351 in the approaching direction, the separation direction, or the direction different from each other, and move the plurality of electrodes 351 to the substrate 211 , 213 to the side, or exit from around the base plate 211, 213. In addition, the electrode driving device 352 may only withdraw from the side without moving the plurality of electrodes 351 to the side of the substrates 211 and 213.

In addition, when the upper stage 322 is raised and lowered with a sufficient stroke and the microscope 324 has a sufficiently large focal depth, the upper stage 322 and the download stage 332 can also be raised and lowered to move the plurality of electrodes 351 to the sides of the substrates 211 and 213. And withdraw from the side to replace the electrodes 351 ascending and descending. In this case, the electrode driving device 352 may not be provided. In addition, it is also possible to move a part of the electrodes 351 of the plurality of electrodes 351, and it is not necessary to move all the electrodes 351.

The detection unit 353 detects the electrostatic characteristics between at least a pair of electrodes included in the plurality of electrodes 351. The electrostatic characteristics can be detected by, for example, inputting an AC voltage between a pair of electrodes, detecting the resulting AC current, and calculating the impedance from the ratio of the AC voltage to the current. The detection result is transmitted to the control device 150. Thereby, the position and movement of the substrate 211 in the Z-axis direction can be detected, and the state of the expansion process of the contact area of the substrates 211 and 213 during bonding can be detected. The detection unit 353 may also be provided in pairs of electrodes, or may be provided in common for all electrode pairs.

The example shown in FIG. 4A is that a plurality of electrodes 351 includes a combination of a plurality of pairs of two electrodes, and includes: an electrode pair 351A with two electrodes 351a; an electrode pair 351B with two electrodes 351b; and two electrodes The electrode pair 351C of 351c; the electrode pair 351D with two electrodes 351d; and the electrode pair 351E with two electrodes 351e. In addition, as shown in FIG. 4A, detection units 353a to 353e may be provided for each electrode pair 351A to 351E. In this case, the detection units 353a to 353e independently detect the gap between the two electrodes 351a to 351e constituting the corresponding electrode pair in the electrode pairs 351A to 351E (for example, the detection unit 353a detects the gap between the two electrodes 351a constituting the electrode pair 351A). The electrostatic characteristics of the sensor, and the detection result is transmitted to the control device 150. In addition, one detection unit 353 may be provided for a plurality of electrode pairs 351A to 351E, respectively. In this case, the detection unit 353 may use AC signals of different frequencies for each of the plurality of electrode pairs 351A to 351E to detect electrostatic characteristics. Thereby, it is possible to superimpose the respective detection signals to detect the electrostatic characteristics at one time without crosstalk. Or, as shown in FIG. 4B, a selector 354 that randomly selects two from the plurality of electrodes 351a to 351e and regroups into any one of the plurality of electrode pairs 351A to 351E can be further provided, and the selector 354 depends on A plurality of electrode pairs 351A to 351E are connected to the detection unit 353 sequentially. The detection unit 353 sequentially detects the electrostatic characteristics between the respective two electrodes 351 a to 351 e of the electrode pair 351A to 351E connected by the selector 354, and transmits the detection result to the control device 150.

In addition, the control device 150 includes: a judgment unit 150a for judging the state of the contact area based on the electrostatic characteristic detection result between each of the two electrodes 351a-351e of the electrode pair 351A-351E; and control substrates 211, 213 based on the judgment result of the judgment unit 150a The control section 150b of the inclination of the space. When the judging unit 150a determines that the expansion of the contact area 215 is not the same, the control unit 150b controls the download stage 332 to increase or decrease the distance between the substrate 213 and the substrate 211 with the expansion of the contact area 215 in a rapid or slow direction. With the slope method, the contact area 215 can be enlarged in the same way.

4A and 4B show an example of the arrangement of the plurality of electrodes 351 of the bonding detection device 350 in a head-up view. An example of the substrates 211 and 213 is one in which a contact area 215 is formed by contacting a part of the center of each. In addition, the vertical direction on the drawing is the vertical direction, and the horizontal direction on the drawing is the horizontal direction.

The two electrodes 351a to 351d included in the four electrode pairs 351A to 351E are arranged to face each other across the edges of the substrates 211 and 213 respectively supported by the upper stage 322 and the download stage 332. The pair of electrodes 351a are arranged in the vertical direction to sandwich the left edges of the substrates 211 and 213 separated from the contact area 215 in the left direction. The pair of electrodes 351b are arranged in the vertical direction to sandwich the right edges of the substrates 211 and 213 separated from the contact area 215 in the right direction. The pair of electrodes 351c are arranged in a horizontal direction across the upper edges of the substrates 211 and 213 separated from the contact area 215 in the upper direction. The pair of electrodes 351d are arranged in a horizontal direction across the lower edges of the substrates 211 and 213 separated from the contact area 215 in the downward direction. By detecting the electrostatic characteristics between the respective two electrodes 351a to 351d of the electrode pairs 351A to 351D, the end of the expansion of the contact area can be detected at each edge.

The two electrodes 351e included in the electrode pair 351E are on a straight line passing through the center of the contact area 215 in the plane direction, on the sides of the substrates 211 and 213 supported by the upper stage 322 and the download stage 332, that is, on the plane Depending on the time, they are arranged opposite to each other on the upper right and lower left of each. By detecting the electrostatic characteristics of the pair of electrodes 351e, the expansion process of the contact area when the substrate is attached can be detected.

In addition, the electrode 351e has an electrode surface larger than the electrodes 351a to 351d. As shown in FIGS. 4A and 4B, when the electrode 351e is arranged outside the electrodes 351a-351d without interference with the electrodes 351a-351d in a head-up view, the signal intensity obtained by the electrode pair 351E can be maintained relative to the The signal intensity obtained by the other electrode pairs 351A to 351D will not decrease.

5A to 6B further show another example of the arrangement of a plurality of electrodes 351.

The example shown in FIG. 5A is a plurality of electrodes 351 including a plurality of pairs of two electrode groups, including: an electrode pair 351A with two electrodes 351a; an electrode pair 351B with two electrodes 351b; and an electrode pair 351B with two electrodes 351c The electrode pair 351C; and the electrode pair 351D with two electrodes 351d. The two electrodes 351a to 351d included in the four electrode pairs 351A to 351D respectively sandwich the contact area 215 in the plane direction, and are arranged opposite to each other on the sides of the substrates 211 and 213 at an angular interval of 45 degrees. By detecting the respective electrostatic characteristics of the electrode pairs 351A to 351D, it is possible to detect the expansion process of the contact area 215 in each direction when the substrate is attached. In addition, the number of electrode pairs is not limited to four, and may be a plurality of two or more.

The example shown in FIG. 5B is a modification of the example shown in FIG. 5A, and is provided with a guide 355 that rotatably supports the two electrodes 351a included in the electrode pair 351A in the circumferential direction of the substrates 211 and 213. Two The electrodes 351a are arranged on the sides of the substrates 211 and 213 opposite to each other with the contact area 215 sandwiched in the surface direction, and the positions along the guide 355 in the circumferential direction can be changed arbitrarily. By changing the circumferential position of the two electrodes 351a and detecting the electrostatic characteristics between them, it is possible to detect the expansion process of the contact area 215 in any direction during substrate bonding. In addition, the number of electrode pairs is not limited to one, and may be plural.

The example shown in FIG. 6A is a plurality of electrodes 351 including a plurality of pairs of two electrode groups, including: an electrode pair 351A having two electrodes 351a; an electrode pair 351B having two electrodes 351b; and an electrode pair 351B having two electrodes 351c The electrode pair 351C; the electrode pair 351D with 2 electrodes 351d; the electrode pair 351E with 2 electrodes 351e; the electrode pair 351F with 2 electrodes 351f; the electrode pair 351G with 2 electrodes 351g; and the electrode pair 351G with 2 electrodes 351h electrode pair 351H. The two electrodes 351a to 351h included in each of the eight electrode pairs 351A to 351H are arranged to face each other while sandwiching the substrates 211 and 213 on the sides of the substrates 211 and 213.

When the three electrode pairs 351A to 351C are viewed in a horizontal view, the two electrodes 351a to 351c included in each pair sandwich the left edge portion of the substrates 211, 213, the center contact area 215, and the right edge portion in the vertical direction However, they are arranged apart from each other in the horizontal direction. Here, one of the electrodes 351a to 351c of each pair is arranged on a straight line in the lateral direction on the substrates 211 and 213, and the other electrode 351a to 351c is arranged on a straight line in the lateral direction under the substrates 211 and 213.

In a plan view of the three electrode pairs 351D to 351F, the two electrodes 351d to 351f included in each pair sandwich the upper edges of the substrates 211 and 213, the center contact area 215, and the lower edge in the horizontal direction. The arrangement is separated from each other in the longitudinal direction. Here, one of the electrodes 351d to 351f of each pair is arranged on a straight line in the vertical direction on the left of the substrates 211 and 213, and the other electrode 351d to 351f is arranged on a straight line in the vertical direction on the right of the substrates 211 and 213.

The two electrodes 351 g included in the electrode pair 351G are arranged on the upper right and lower left of the substrates 211 and 213 with the contact area 215 sandwiched therebetween in a horizontal view.

The two electrodes 351h included in the electrode pair 351H are arranged on the upper left and lower right of the substrates 211 and 213 with the contact area 215 sandwiched therebetween in a horizontal view.

By detecting the respective electrostatic characteristics of the electrode pairs 351A to 351H, the expansion process of the contact area 215 in the longitudinal direction can be detected from the electrostatic characteristics of the electrode pair 351B, together with the detection of the end from the electrostatic characteristics of the electrode pairs 351D and 351F, In addition, the expansion process of the contact area 215 in the horizontal direction can be detected from the electrostatic characteristics of the electrode pair 351E, and the end can be detected from the electrostatic characteristics of the electrode pair 351A, 351C, and the contact area 215 can be detected from the electrostatic characteristics of the electrode pair 351G, 351H. Expansion process in each oblique direction.

The example shown in FIG. 6B is a modification of the example shown in FIG. 6A, and is provided with a pair of guides 356 that movably support the two electrodes 351a included in the electrode pair 351A in the horizontal direction; A pair of guides 357 that movably supports the two electrodes 351d included in the electrode pair 351D.

One of the two electrodes 351a is arranged on one side of the substrates 211 and 213 in the longitudinal direction, and the other is arranged on the other side, and faces each other with the substrates 211 and 213 therebetween. By moving the two electrodes 351a along the guide 356, the position of the electrode pair 351A in the horizontal direction can be arbitrarily changed. By changing the position of the electrode pair 351A in the horizontal direction, and detecting the electrostatic characteristics between the two electrodes 351a included in the electrode pair 351A, it is possible to detect the expansion process of the contact area 215 at each position in the horizontal direction when the substrate is attached. end. In addition, the number of electrode pairs 351A may be plural, and is not limited to one.

One of the two electrodes 351d is arranged on one side of the substrates 211 and 213 in the lateral direction, and the other is arranged on the other side, and faces each other with the substrates 211 and 213 therebetween. By moving the two electrodes 351d along the guide 357, the position of the electrode pair 351D in the longitudinal direction can be arbitrarily changed. By changing the position of the electrode pair 351D in the vertical direction, and detecting the electrostatic characteristics between the two electrodes 351d included in the electrode pair 351D, it is possible to detect the expansion process of the contact area 215 at each position in the vertical direction when the substrate is attached. end. In addition, the number of electrode pairs 351D may be plural, and is not limited to one.

The bonding principle of the substrates 211 and 213 will be described below.

FIG. 7A schematically shows the cross-sectional structure of the holder 221 holding the substrate 211 that has been carried into the bonding apparatus 300. The holder 221 sucks and holds the substrate 211 on the holding surface 222 by an electrostatic chuck, a vacuum chuck, or the like. Here, the holding surface 222 has a curved shape with a high central side and a low peripheral edge. Thereby, the substrate 211 sucked and held on the holding surface 222 and the holding surface 222 are brought into close contact with each other and bends into a convex shape protruding from the center side, and the shape thereof is maintained. In addition, the shape of the holding surface 222 of the holder 221 may also be a spherical surface, a parabolic surface, a cylindrical surface, or the like. In the bonding apparatus 300, the substrate 211 bent into a convex shape is supported on the upper stage 322 via the holder 221.

FIG. 7B schematically shows the cross-sectional structure of the holder 223 holding the substrate 213. The holder 223 sucks and holds the substrate 213 on the holding surface 224 by an electrostatic chuck, a vacuum chuck, or the like. Here, the holding surface 224 has a flat shape. Thereby, the substrate 213 sucked and held on the holding surface 224 and the holding surface 224 are brought into close contact with each other to form a flat surface and maintain its shape. In the bonding apparatus 300, the substrate 213 is supported by the loading table 332 via the holder 223.

FIG. 8A shows a state in which two substrates 211 and 213 are aligned in the substrate bonding process. The substrate 211 is held by the holder 221, the center is bent into a convex shape, and is supported downward on the upper stage 322 via the holder 221, and the substrate 213 is held flat on the holder 223, and is supported on the download stage 332 via the holder 223 upward. , And drive the download stage 332 in the surface direction to position the substrate 213 directly below the substrate 211. In addition, at least one surface of the substrates 211 and 213 is activated by plasma exposure using activation devices 326 and 336. At this time, the plurality of electrodes 351 of the bonding detection device 350 are arranged on the sides of the substrates 211 and 213 by the electrode driving device 352.

FIG. 8B shows a state in which a contact area 215 is formed between the two substrates 211 and 213 in the substrate bonding process. With the center of the substrate 211 supported on the upper stage 322 via the holder 221 bent into a convex shape, the loading stage 332 is approached toward the upper stage 322 by the lift drive 338, and the download stage 332 is flatly supported by the holder 223. The substrate 213 of the stage 332 is pressed against the substrate 211 so that the centers of the substrates 211 and 213 are in close contact. Thereby, a contact area 215 serving as a starting point for bonding is formed in the center of the substrates 211 and 213. At this time, the periphery of the substrate 211 is separated from the substrate 213.

FIG. 8C shows a state in which the bonding wave is progressing in the substrate bonding process. The holder 221 held by the upper stage 322 is released, and the substrate 211 is released from the upper stage 322. At this time, in such a way that at least one of the surfaces of the substrates 211 and 213 is activated, the contact area 215 will be enlarged due to the intermolecular force between the substrates 211 and 213 in a manner that the adjacent areas of the respective substrate surfaces are automatically attracted to each other. To the surroundings. As a result, the bonding wave 232, that is, the boundary between the contact area of the substrates 211, 213 and the non-contact area that has not been in contact, moves from the center of the substrates 211, 213 to the surroundings, and the contact area 215 expands to perform the substrates 211, 213. The fit.

FIG. 8D shows the state where the substrate bonding is completed in the substrate bonding process. The bonding wave 232 moves to the periphery of the substrates 211 and 213, and when the contact area 215 expands to the entire substrates 211, 213, the substrates 211, 213 are bonded to each other to form a bonded substrate 230.

In the bonding principle of the substrates 211, 213, the contact area 215 of the substrates 211, 213 expands from the center of the substrates 211, 213 toward the periphery. As a result, the ambient gas sandwiched between the substrates 211 and 213 before bonding, such as the atmosphere, is extruded to the outside in the process of expanding the contact area of the substrates 211 and 213, thereby preventing the bonding of the substrates 211, 211 and 213. Air bubbles remain among 213.

In addition, in this embodiment, the case where the substrate 211 deformed into a convex shape and the flat substrate 213 are bonded together is exemplified. For example, when both the substrates 211 and 213 are deformed into a convex shape, the substrates 211 and 213 are transformed into each other. In the case of convex and concave shapes with different curvatures, and in the case of deforming the substrates 211 and 213 into a cylindrical shape with a non-parallel central axis, the contact area 215 can be formed between the substrates 211 and 213 and enlarged. The way it fits.

9A and 9B show the electrode shape of the electrode 351 and the principle of displacement detection of the substrate 211. As explained using FIGS. 8A to 8D, in the substrate bonding process, the substrates 211, 213 are performed so that the bonding wave 232 moves from the center of the substrates 211, 213 to the surroundings, and the contact area 215 between the substrates 211, 213 is enlarged. fit. Here, the electrode surface of the electrode 351 has a circular shape, and the electrode 351 is arranged such that the end surface of the substrate 211 is opposed to the upper half of the circular electrode surface. Thereby, the end surface of the substrate 211 _{moves from the position Z 1 in the} Z-axis direction to a lower position Z ₂ , and accordingly, the area of the electrode portion opposite to the end surface of the substrate 211 _{increases from S 1} to S ₂ , and the electrodes 351 and The electrostatic capacitance between the other electrodes 351 facing this _{increases from C 1 =εS 1} /D to C ₂ =εS ₂ /D. Here, ε is the dielectric constant of the substrate 211, the separation distance of the D-type electrodes, and the electrostatic capacitance between the electrodes are assumed to be dominated by the substrate 211. Therefore, it is possible to detect the position of the substrate 211 in the Z-axis direction by detecting the change of the electrostatic capacitance between the two electrodes 351, thereby detecting the expansion process of the contact area 215 formed between the substrates 211 and 213.

FIG. 9C shows an example of the displacement detection result of the substrate 211 during the bonding process of the substrates 211 and 213. This example shows the time-dependent change of the electrostatic capacitance detection result of a pair of electrodes 351e in FIG. 4A. This time change reflects the movement of the substrate 211 in the electric field between the two electrodes 351e. The bonding of the substrates 211 and 213 is started at time 10 seconds by releasing the holding of the substrate 211 by the upper stage 322. Along with this, the electrostatic capacitance _{increases from the value C 1} , and is substantially constant during the period T from 12 to 18 seconds at the time of lamination, and then increases again to saturate to C ₂ . By this, the lamination is completed in 24 seconds at time. From the time change of the electrostatic capacitance, the expansion of the bonding wave 232, that is, the expansion process of the contact area 215 can be read.

FIG. 9D shows another example of the detection result of the displacement of the substrate 211 during the bonding process of the substrates 211 and 213. This example shows the change of the electrostatic capacitance detection result of the pair of electrodes 351a in FIG. 4A with time. The bonding of the substrates 211 and 213 starts at time 16 seconds when the holding of the substrate 211 by the upper stage 322 is released. Along with this, the electrostatic capacitance _{increases from the value C 1} , and is substantially constant during the period T from 18 to 26 seconds at the time of bonding, and then increases again to saturate to C ₂ . Thereby, the bonding wave 232 expands at time 35 seconds, which can be interpreted as the expansion of the contact area 215 reaching the left edges of the substrates 211 and 213 and the bonding is completed.

10A and 10B show another principle of the electrode shape of the electrode 351 and the displacement detection of the substrate 211. In this example, the electrode surface of the electrode 351 has a circular shape, and the electrode 351 is arranged such that the end surface of the substrate 211 is opposed to the lower half of the circular electrode surface. Thereby, the end face of the substrate 211 _{moves from the position Z 1 in the} Z-axis direction to a lower position Z ₂ , and accordingly, the area of the electrode portion opposite to the end face of the substrate 211 is _{reduced from S 1} to S ₂ , and the electrodes 351 and The electrostatic capacitance between the opposite electrode 351 is _{reduced from C 1} =εS ₁ /D to C ₂ =εS ₂ /D. Here, ε is the dielectric constant of the substrate 211, the separation distance of the D-type electrodes, and the electrostatic capacitance between the electrodes are presumably determined by the substrate 211. It is understood that even according to the arrangement of the electrodes, it is possible to detect the change of the electrostatic capacitance between the two electrodes 351, and to detect the position of the substrate 211 in the Z-axis direction, thereby detecting the contact area 215 formed between the substrates 211 and 213 The expansion process.

FIG. 10C shows an example of the detection result of the displacement of the substrate 211 during the bonding process of the substrates 211 and 213. In this example, the result of the electrostatic capacitance detection of a pair of electrodes 351e in FIG. 4A is shown as a function of time. The bonding of the substrates 211 and 213 starts at time 12 seconds by releasing the holding of the substrate 211 by the upper stage 322. Along with this, the electrostatic capacitance _{decreases from the value C 1} , and is substantially constant during the period T from 17 to 23 seconds at the time of lamination, and then decreases again to saturate to C ₂ . With this, the bonding ends at time 37 seconds. From the time change of the electrostatic capacitance, it can be interpreted as the expansion of the bonding wave 232, that is, the expansion process of the contact area 215.

In addition, even in any of the examples in FIG. 9C, FIG. 9D, and FIG. 10C, there is still a period in which the change in capacitance is extremely small, regardless of the bonding process. Therefore, the judging unit 150a judges that the bonding has started from the beginning of the change in the electrostatic capacitance, and sets a specified period including a period in which the electrostatic capacitance change is extremely small, for example, about 10 seconds, as the mask period, and after the end of the mask period The end of bonding is determined by the saturation of the electrostatic capacitance.

In addition, as shown in the example shown in FIGS. 9C and 10C, by detecting the change of the electrostatic capacitance between the pair of electrodes 351e, it is possible to understand the expansion of the junction wave 232 related to the direction in which the electrodes 351e are arranged, that is, the contact area 215 Expand it. Therefore, by bonding the detection device 350 (also an example of an uneven detection mechanism for the expansion of the contact area 215), for example, the electrode pairs 351A to 351D arranged as shown in FIG. During the bonding process of the test substrates, the electrostatic capacitance detection results change with time, and the way to grasp the relationship with the expansion of the contact area 215 can be determined by the capacitance of the electrode pairs 351A to 351D in the bonding process of the substrates 211 and 213. As a result of the detection, the progress speed of the expansion of the contact area 215 in the arrangement direction of the individual electrode pairs, especially the uneven progress of the expansion, is detected.

11A and 11B show the other electrode shape of the electrode 351 and the principle of displacement detection of the substrate 211. In this example, the electrode surface of the electrode 351 has a rectangular shape and is arranged obliquely with respect to the Z-axis direction. As a result, the end surface of the substrate 211 _{moves from the position Z 1 in the} Z-axis direction to a lower position Z ₂ , and accordingly, the area of the electrode portion opposite to the end surface of the substrate 211 remains S unchanged, but it is replaced by the electrode and the substrate The separation distance of the end face of 211 is _{reduced from D 1} to D ₂ , and the electrostatic capacitance between the electrode 351 and the opposite electrode 351 _{increases from C 1} =ε ₀ S/D ₁ to C ₂ =ε ₀ S/D ₂ . Here, ε ₀ is the dielectric constant of the atmosphere, and it is assumed that the change of the electrostatic capacitance between the electrodes is dominated by the change of the distance of the atmosphere. It is understood that even according to the arrangement of the electrodes, it is possible to detect the change of the electrostatic capacitance between the two electrodes 351, and to detect the position of the substrate 211 in the Z-axis direction, thereby detecting the contact area 215 formed between the substrates 211 and 213 The expansion process.

In addition, even when an electrode having a circular shape as shown in FIG. 9A is used, it can be arranged on the side of the substrate inclined with respect to the Z axis, and it is not limited to the case of the rectangular electrode shown in FIG. 11A. Thereby, the detection sensitivity of the electrostatic characteristics between the two electrodes 351 can be improved.

FIG. 12 shows the flow of the substrate bonding step by the bonding device 300. In addition, the board bonding system 100 constitutes various parts and operates under the control of the control part 150b of the control device 150. Prior to the substrate bonding, the substrate cassette 120 for accommodating the bonded substrate 210 and the substrate cassette 130 for accommodating the bonded substrate 230 are fixed to the frame 110. In addition, the plurality of electrodes 351 are raised by the electrode driving device 352 and retracted to the side of the upper stage 322.

In step S101, the substrate 210 is carried into the bonding apparatus 300. As shown in FIG. 13A, the holder 221 is taken out from the holder temporary storage box 400 by the transport device 140 and transported to the pre-aligner 500, and the substrate 211 is taken out from the substrate cassette 120 and transported to the pre-aligner 500, so that the substrate 211 is held by the holder 221. The holder 221 holding the substrate 211 is carried into the bonding apparatus 300, and the substrate 211 is fixed to the upper stage 322 facing downward. In addition, the holder 223 is taken out from the holder temporary storage box 400 by the transport device 140 and transported to the pre-aligner 500, and the substrate 213 is taken out from the substrate cassette 120 and transported to the pre-aligner 500, so that the substrate 213 is held in Holder 223. The holder 223 holding the substrate 213 is carried into the bonding apparatus 300, and the substrate 213 is fixed to the download table 332 with the substrate 213 facing upward.

Then, the position of the download station 332, that is, the relative position of the microscopes 324 and 334, is calibrated. The detailed steps are as described above.

In step S102, the respective alignment marks of the substrates 211 and 213 are detected using microscopes 324 and 334. As shown in FIG. 13B, under the control of the control device 150, the interferometer 341 measures the position of the download platform 332, and according to the measurement result, drives the download platform 332 in the horizontal direction by the X-direction drive unit 331 and the Y-direction drive unit 333 , And the alignment marks of the substrate 213 are successively positioned in the field of view of the microscope 324 and detected by the microscope 324. In addition, under the control of the control device 150, the interferometer 341 measures the position of the download table 332, and drives the download table 332 in the horizontal direction by the X-direction drive unit 331 and the Y-direction drive unit 333 according to the measurement result, and the substrate 211 The alignment marks are successively positioned in the field of view of the microscope 334 and detected by the microscope 334. From the measurement results of the interferometer 341 and the inspection results of the microscopes 324 and 334, the mutual positional relationship of the alignment marks of the substrates 211, 213, that is, the positional relationship of the substrates 211, 213, is determined.

In step S103, the surfaces of the substrates 211 and 213 are activated by the activation devices 326 and 336. As shown in FIG. 13C, the surface of the substrate 213 is exposed to plasma by the activation device 326, and the surface of the substrate 211 is exposed to the plasma by the activation device 336, which is driven by the X-direction driving portion 331 and the Y-direction drive. The part 333 drives the download stage 332 in the direction of the arrow S, and activates it by cleaning the entire substrates 211 and 213. Thereby, when the substrates 211 and 213 are brought into contact, the substrates 211 and 213 are bonded to each other and integrated.

In addition, the substrates 211 and 213 may also be activated by mechanical treatment such as polishing and chemical treatment such as cleaning. In addition, the substrates 211 and 213 may also be activated by sputter etching using inert gas, ion beam, or high-speed atomic beam. When an ion beam or a high-speed atomic beam is used, the bonding device 300 can be produced under reduced pressure. In addition, the substrates 211 and 213 may also be activated by irradiating ultraviolet rays, an ozone ashing machine, or the like. In addition, for example, a liquid or gas etchant can also be used to chemically purify the surfaces of the substrates 211 and 213 for activation. In addition, multiple types of activation methods can also be used in combination.

In addition, the activation devices 326 and 336 may also be provided outside the laminating device 300 instead of inside. At this time, the surfaces of the substrates 211 and 213 may be activated before the substrates 211 and 213 are carried into the bonding apparatus 300, and then the activated substrates 211 and 213 may be carried into the bonding apparatus 300.

In step S104, the substrate is corrected in such a way that at least one of the temperature-regulated substrates 211 and 213 compensates for the difference in magnification with respect to the design specifications. The warpage of the substrates 211 and 213 may be deformed by methods other than temperature adjustment, for example, a correction method of deforming at least one of the substrates 211 and 213 by using an actuator provided on the loading stage 322 or the downloading stage 332. Thereby, even under the inherent strain on the respective substrates 211, 213, the substrates 211, 213 can still be accurately aligned.

In addition, the order of step S103 of activating the substrates 211 and 213 and step S104 of the temperature adjusting substrates 211 and 213 may be exchanged. In addition, before step S102 of detecting the respective alignment marks of the substrates 211 and 213, step S104 of correcting at least one of the temperature-regulating substrates 211 and 213 may be performed.

In step S105, the bonded substrates 211 and 213 are aligned with each other. As shown in FIG. 13D, according to the predetermined positional relationship of the substrates 211 and 213, the X-direction driving part 331 and the Y-direction driving part 333 drive the download table 332, and the substrate 211 is positioned in the horizontal direction so that the gap between the alignment marks The position deviation is the smallest statistically or below the threshold. Here, the enhanced global alignment (Enhanced Global Alignment) can be used as the statistical alignment method.

In step S106, the plurality of electrodes 351 of the bonding detection device 350 are arranged on the sides of the substrates 211 and 213. As shown in FIG. 13E, the download table 332 is driven upward so that the lift drive part 338 is raised. Thereby, the substrate 213 supported by the download station 332 approaches the substrate 211 supported by the upload station 322. In this state, as explained using FIG. 8A, the electrode driving device 352 lowers the plurality of electrodes 351 of the bonding detection device 350, and the substrates 211 and 213 are sandwiched in the surface direction and arranged on these sides. square.

In step S107, parts of the substrates 211 and 213 are brought into contact with each other to form a starting point for bonding. As shown in FIG. 13F, the loading table 332 supporting the substrate 213 is driven upward in such a manner that the lifting driving portion 338 is raised. Thereby, as explained using FIG. 8B, the center of the substrate 213 is pressed to the substrate 211, and the ambient gas sandwiched between the substrates 211 and 213 is extruded, and the respective parts of the substrates 211 and 213 are in contact with each other to form a contact area. 215, and form the starting point for bonding. The starting point may also be a region having an area.

By this contact, the contact areas of the activated substrates 211, 213 are bonded by chemical bonding such as hydrogen bonding. After contacting a part of the substrates 211 and 213, the state where the substrates 211 and 213 are in contact with each other is maintained. At this time, the contact area can also be enlarged by pressing the substrates 211 and 213 to increase the area of a part of the contact area. When a specified time elapses while maintaining the contact state, a bonding force is maintained between the substrates 211 and 213 so as not to cause positional deviation between the substrates 211 and 213 during the bonding process of the substrates 211 and 213. Thereby, a starting point for bonding is formed at a portion where the substrates 211 and 213 are in contact with each other.

In step S108, a contact area is formed between the substrates 211 and 213, and it is checked whether the above-mentioned predetermined magnitude of bonding force is maintained between the two substrates 210. When it is detected that the substrates 211 and 213 have been bonded at this stage, it is investigated whether a bonding starting point has been formed, which becomes an opportunity for the substrates 211 and 213 to start bonding. Therefore, in step 107, it is investigated whether an area that presses a part of the substrates 211 and 213 has been formed, or an area that becomes a starting point for bonding has been formed at a position close to the area.

When it is judged that the bonding starting point has been formed on the substrate 210, that is, when it is judged that the predetermined magnitude of the bonding force is maintained between the contacting parts of the two substrates 211 and 213, the process proceeds to the next step S109. When it has not been confirmed that the starting point has been formed on the substrates 211 and 213, both the substrates 211 and 213 are maintained, and a part of the substrates 211 and 213 is continuously pressed to form the bonding starting point.

In step S109, the holding of the substrate 211 by the holder 221 is released. As a result, the substrate 211 is released. As described with reference to FIG. 8C, the area adjacent to the contact area is automatically adsorbed by the intermolecular force between the substrates 211 and 213, resulting in a bonding wave in which the contact area expands sequentially in the surface direction. As a result, the substrate 211 is strained and the substrates 211 and 213 are bonded.

In addition, the so-called bonding of the substrates 211 and 213 means that the main surfaces of the substrates 211 and 213 are superimposed parallel to each other, and their relative positions are fixed by hydrogen bonding, Van der Waals bonding, covalent bonding, and the like. On the other hand, the so-called overlapping substrates 211 and 213 refer to a state where the main surfaces of the substrates 211 and 213 are in contact with each other, but it is not limited to a state where the relative positions of the substrates 211 and 213 are fixed. In addition, sometimes "stacked" is used and synonymous with "overlap". In addition, although the substrates 211 and 213 may start to be joined at the place where they are laminated, they may also be carried out from the joining area (in this embodiment, the area directly under the upper stage 322) during the joining process, and are aligned with the substrate. The location of different locations is joined together. In addition, there are cases where the substrates 211 and 213 are bonded by heating, pressing, or the like at a location other than the alignment location.

In step S110, the bonding detection device 350 is used to determine the state of the contact area. For example, it is possible to detect the respective electrostatic characteristics of a plurality of electrode pairs 351A to 351E in the configuration shown in FIG. 4A. The determination unit 150a is used to determine the time change of the detection results of the respective electrostatic characteristics as explained using FIGS. 9A to 10C. The state of the contact area.

Step S111 is to investigate whether the contact area of the substrates 211, 213 is expanding from the starting point of bonding formed on the substrates 211, 213. When it has been confirmed that the contact area of the substrates 211 and 213 is expanding, the judgment unit 150a judges that the substrates 211 and 213 are being bonded, and proceeds to the next step S112. When it cannot be confirmed, the judgment unit 150a judges that the substrates 211 and 213 are The bonding is blocked for some reason, and the process proceeds to step S114.

Here, the inclination between the substrates 211 and 213 can also be controlled based on the detection results of the electrostatic characteristics of the plurality of electrode pairs 351A to 351E. For example, from the detection results of the respective electrostatic characteristics of the plurality of electrode pairs 351A to 351E in the configuration shown in FIG. 4A, the change in the electrostatic characteristics of the electrode pair 351A with time is relative to the electrostatic characteristics of the other electrode pairs 351B to 351E. When the change is early or delayed, the determining unit 150a determines that the progress of the expansion of the contact area is uneven, and the expansion of the contact area in this direction is earlier or delayed compared to the expansion in other directions. The control unit 150b controls the download station 332 according to the judgment of the judgment unit 150a to further increase or decrease the slope of the substrate 213 relative to the left of the substrate 211. Thereby, the contact area 215 can be expanded uniformly.

In addition, when at least one of the upper stage 322 and the download stage 332 is provided with an actuator that mechanically deforms the substrates 211 and 213, the control unit 150b can also control the driving amount of the actuator according to the judgment of the judgment unit 150a to adjust The amount of deformation of the substrates 211 and 213. In addition, when at least one of the upper stage 322 and the download stage 332 is provided with heaters for the temperature adjustment substrates 211 and 213, the control unit 150b may also control the temperature adjustment amount of the heater based on the judgment of the judgment unit 150a to adjust the substrate The amount of deformation of 211 and 213. In addition, the upper stage 322 is provided with a vent hole penetrating in the thickness direction, and a communicating vent hole is also provided in the holder 221 holding the substrate 211. When the structure is configured to pass fluids such as dry air and inert gas from the outside of the laminating device 300 When the grooves are sprayed to the substrate 211 through the vent holes of the upper stage 322 and the holder 221, the control section 150b can also adjust the flow rate from the vent holes corresponding to the slow or accelerated area of the contact area according to the judgment of the judgment section 150a. Fluid pressure. In addition, the holding surface of the holder 221 can also be divided into a plurality of partitions along at least one of the radial direction and the circumferential direction, and the suction force of vacuum adsorption or electrostatic adsorption can be controlled according to the partitions. At this time, it is also possible to control the time point of releasing the substrate 211 from the holder 221 in accordance with the speed of the expansion of the expansion area according to the zone. In this way, when the holding of the substrate 211 by the holder 221 can be released inconsistently, the control unit 150b can also control according to the judgment of the judgment unit 150a to absorb the suction of the partition corresponding to the slow expansion area in the contact area. The adsorption release of the partition corresponding to the expanded acceleration area is released at an earlier time. In addition, the holding surface of the holder 223 can also be divided into a plurality of partitions along at least one of the radial direction and the circumferential direction, and the suction force of vacuum adsorption or electrostatic adsorption can be controlled according to the partitions, and corresponding to the expansion speed of the contact area , Control the expansion of the contact area by zone. In this way, when the holding of the substrate 213 by the holder 223 can be released inconsistently, the control part 150b can also control according to the judgment of the judgment part 150a, and the adsorption force of the partition corresponding to the slow expansion area of the contact area is lower than The adsorption force of the partition corresponding to the accelerated expansion area is still weak. In addition, it is also possible to adjust the gap between the substrates 211 and 213 by driving the download table 332 supporting the substrate 213 to the upper or lower side by the lifting driving part 338.

In addition, when the expansion speed of the contact area is faster than the predetermined speed, the control unit 150b can correct the control of the expansion speed of the contact area of the substrates 211 and 213 and the magnification non-linear correction even during the bonding process of the substrates 211 and 213. control. For example, it is only necessary to detect that the magnification generated in the bonding process is different from the predetermined one by the individual differences of the substrate and the changes in the environment, and then correct it. The predetermined speed can be set according to the detection result of the expansion speed of the contact area obtained in the substrate bonding. The relationship between the magnification (non-linear) generated in the substrate bonding process and the expansion speed of the contact area is grasped in advance based on the data of the same type of substrate. Set the expansion speed in the same way that the magnification (non-linear) that occurs during the substrate bonding process is the same as that of the previously bonded substrate. In addition, when it is necessary to predict changes in the magnification rate and the expansion speed of the contact area under environmental factors, etc., they will also be predicted to set the predetermined speed.

The control unit 150b can also control the download station 332 immediately, or when the next substrate is attached. In addition, it can also be implemented for each batch of substrates and whenever the bonding treatment plan is changed.

In addition, in step S111, the judging unit 150a may further detect the expansion speed or degree of expansion of the contact area 215 of the substrates 211, 213 to predict the time for the completion of the bonding of the substrates 211, 213. The expansion speed or degree of expansion of the contact area 215 can be calculated, for example, from the topography of the electrostatic characteristics between the two electrodes 351 shown in FIG. 9C, FIG. 9D, and FIG. 10C over time.

In addition, the detection results of the respective electrostatic characteristics of the plurality of electrode pairs 351A to 351D in the configuration shown in FIG. 5A or FIG. shape. The shape of the contact area 215 changes along with its expansion. Therefore, when the contact area 215 maintains a circular shape, the judgment unit 150a judges that the bonding of the substrates 211 and 213 is normally performed, and proceeds to the next step S112. When the deviation from the circular shape becomes large and the circular shape cannot be maintained, it is judged The part 150a judges that the bonding of the substrates 211 and 213 has not been performed normally, and proceeds to step S114.

In step S112, it is checked whether the bonding of the substrates 211 and 213 has been completed. The judgment unit 150a can confirm that the bonding is completed by disappearing the respective electrostatic characteristics of the plurality of electrode pairs 351A to 351E over time and saturating to a certain value. Here, as the use of 9C, the to Figure 9D, the description and 10C, two electrode pairs 351A ~ 351E of the respective detection results contained between 351a ~ 351e of the capacitance increases from C _1, through minimal changes _{It saturates into C 2 for} a certain period of time. Here, the judging unit 150a may also when the detection result of the electrostatic capacitance begins to change, after a mask period longer than a certain period, the detection result of the electrostatic capacitance converges to a certain ratio of _{|C 2} | or |C ₂ -C _{1 | When the difference with C 2} is below the threshold value within the range of, confirm that the bonding is completed. Thereby, even if the time required for the bonding of the substrates 211 and 213 is different, the completion of the bonding can be confirmed surely. In addition, when the completion of the bonding of the substrates 211 and 213 cannot be confirmed after the predetermined threshold time is exceeded, the determination unit 150a may determine that the completion of the bonding of the substrates cannot be confirmed. When it is confirmed that the substrate bonding is completed, the process proceeds to the next step S113, and if it cannot be confirmed, the process proceeds to step S114.

In step S113, the bonded substrate 230 formed by bonding the substrates 211 and 213 is carried out. As shown in FIG. 13G, a plurality of electrodes 351 are raised by the electrode driving device 352 and retracted to the side of the upper stage 322, the temperature control of the substrates 211 and 213, etc. are ended, and the download stage 332 is lowered by the raising and lowering driving part 338. The bonding substrate 230 is carried out from the bonding apparatus 300 by the conveying device 140. The bonded substrate 230 is separated from the holders 221 and 223 and is contained in the substrate cassette 130.

In step S114, the operation of stopping the bonding apparatus 300, issuing an alarm to the outside, and carrying out the bonding apparatus 300 of the substrates 211, 213, and the like are performed.

Thereby, the substrate bonding step of the substrates 211 and 213 is completed.

In the substrate bonding apparatus 300 of this embodiment, a contact area 215 is formed between the substrates 211 and 213, respectively, in which a part of the contact area 215 is in contact with each other, so that the contact area 215 is expanded in the direction along the bonding surface to directly bond the substrate The device of 211 and 213, and includes: at least a pair of electrodes 351 arranged with the substrates 211 and 213 sandwiched therebetween in the plane direction; 353. A contact area 215 is formed by contacting a part of each of the substrates 211 and 213. When the contact area 215 is expanded in the surface direction, the detection unit 353 detects the surface direction by sandwiching the substrates 211 and 213 therebetween. The electrostatic characteristics of the at least one pair of electrodes 351 can be configured to detect the state of the contact area 215, that is, the bonding process of the substrates 211 and 213.

In the substrate bonding method of this embodiment, a contact area 215 is formed between the substrates 211 and 213, each of which is in contact with each other, and the substrate 211 is directly bonded to the substrate 211 so that the contact area 215 expands in the direction along the bonding surface. The method of 213, and includes: a stage of arranging at least a pair of electrodes 351 with the substrates 211 and 213 sandwiched therebetween in the plane direction; The contact area 215 is expanded in the surface direction along the bonding surface, and the electrostatic characteristics between the two electrodes included in the at least one pair of electrodes 351 are detected. A contact area 215 is formed by contacting a part of each of the substrates 211 and 213. When the contact area 215 is expanded in the surface direction, at least a pair of electrodes are arranged by sandwiching the substrates 211 and 213 in the surface direction. The electrostatic characteristics of the 351 can detect the state of the contact area 215, that is, the bonding process of the substrates 211 and 213.

In addition, in the bonding apparatus 300 of this embodiment, the substrates 211, 213 are held on the loading table 322 and the downloading table 332 via the holders 221, 223. However, instead of using the holders 221, 223, 223, and directly hold the substrates 211 and 213 on the loading station 322 and the download station 332. At this time, it is sufficient to form the holding surface of the upper stage 322 into a curved shape with a high central side and a low peripheral edge. The substrate 211 is sucked and held on the holding surface of the upper stage 322, and is curved into a convex shape protruding from the center side in close contact with the holding surface, and maintains its shape.

In the bonding apparatus 300 of this embodiment, in order to detect the progress state of the expansion of the contact area 215 of the substrates 211 and 213 by the bonding detection device 350, it is arranged as shown in FIGS. 9A and 9B or FIGS. 10A and 10B The electrode 351, but in order to only detect the end of the expansion of the contact area 215, the electrode 351 may be arranged. 14A and 14B show a variation of the electrode configuration and the principle of displacement detection of the substrate.

In the modified example shown in FIG. 14A, at least one of the pair of electrodes 351 is arranged on the back side of the substrate 211 after being bonded to the substrate 213 with respect to the Z-axis direction. As a result, the expansion of the contact area of the substrates 211 and 213 is in progress. Because the end face of the substrate 211 is opposed to the electrode 351, the electrostatic capacitance of the substrate 211 can be detected from the electrode 351. When the end of the substrate 211, 213 ends, because the end surface of the substrate 211 does not face the electrode 351, the electrode 351 cannot detect the electrostatic capacitance of the substrate 211, but the electrostatic capacitance of the ambient gas. Therefore, when the judging unit 150a detects the electrostatic capacitance of the ambient gas from the result of detecting the electrostatic characteristics between the electrodes 351, it can be judged that the expansion of the contact area 215 is completed, that is, the bonding of the substrate is completed.

In the modified example shown in FIG. 14B, at least one of the pair of electrodes 351 is arranged at a position opposite to the end surface of the substrate 211 after the substrate 213 is bonded with respect to the Z-axis direction. As a result, during the expansion of the contact area of the substrates 211 and 213, since the end surface of the substrate 211 is not opposed to the electrode 351, the electrode 351 detects the electrostatic capacitance of the substrate 211 and the ambient gas mixture. This is regarded as the substrate 211, When the expansion of the contact area of 213 proceeds to the ends of the substrates 211 and 213 and ends, since the end surface of the substrate 211 faces the electrode 351, the electrode 351 detects the electrostatic capacitance of the substrate 211. Therefore, when the judging unit 150a detects the electrostatic capacitance of the substrate 211 from the detection result of the electrostatic characteristics between the electrodes 351, it can be judged that the expansion of the contact area 215 is completed, that is, the bonding of the substrate is completed.

In this embodiment, the plurality of electrodes 351 of the bonding detection device 350 are arranged on the sides of the end faces of the substrates 211 and 213 facing each other. When a plurality of electrodes 351 are opposed to the surfaces of the substrates 211 and 213 to detect these electrostatic characteristics, the electrostatic characteristics of the oxide films formed on the surfaces of the substrates 211 and 213 will vary for each substrate or each position on the same substrate. With the change, it is difficult to uniformly detect the expansion of the contact area of the substrates 211 and 213 using a plurality of electrodes 351 for all substrates or for all positions of a single substrate. In this regard, when a plurality of electrodes 351 are opposed to the end faces of the substrates 211 and 213, since the oxide film on the surfaces of the substrates 211 and 213 hardly affects the electrostatic characteristics, a plurality of electrodes can be used for all the substrates or for all positions of a single substrate 351 uniformly detects the expansion of the contact area of the substrates 211 and 213.

In addition, in this embodiment, one of the two electrodes 351a to 351e included in each of the plurality of electrode pairs 351A to 351E of the bonding detection device 350 may be shared. At this time, the bonding detection device 350 is provided with a rotating mechanism that rotates the common electrode to change its direction so that it is opposed to the other electrode of the two electrodes 351a to 351e included in the plurality of electrode pairs 351A to 351E; And while the common electrode is opposed to the other electrode of the two electrodes 351a to 351e included in any one of the plurality of electrode pairs 351A to 351E by a rotating mechanism, the pair of electrodes 351a to 351e are connected to the detection unit 353 Selector. Thereby, a plurality of electrode pairs 351A-351E can be arranged without interference.

In addition, in the bonding detection device 350 of this embodiment, the centers of the substrates 211 and 213 are brought into contact with each other to form a contact area 215 that becomes the starting point for bonding. However, the starting point for bonding is not limited to the center of the substrates 211 and 213, and may be Any position, such as the edges of the substrates 211 and 213.

In the bonding detection device 350 of this embodiment, the two electrodes included in the plurality of electrodes 351 are arranged by sandwiching the substrates 211 and 213 without contact in the surface direction, but they can be replaced or combined with them. The substrates 211 and 213 are sandwiched and arranged in the direction in which they overlap.

15A and 15B schematically show the configuration of the bonding detection device 350A of the first modification as viewed from the top and side, respectively. Here, FIG. 15B is a cross-sectional view about the reference line BB in FIG. 15A. In addition, the holder 221 and the upper stage 322 are omitted in FIG. 15A. The holders 221 and 223 are omitted in FIG. 15B. The bonding detection device 350A includes an electrode pair 351A, and two electrodes 351a included therein are respectively arranged at the center of the lower surface of the loading platform 322 and the center of the upper surface of the downloading platform 332. By detecting the electrostatic characteristics of the electrode pair 351A, it can be detected whether the center of the substrates 211 and 213 respectively held on the upper stage 322 and the download stage 332 is formed with a contact area 215 serving as a starting point for bonding.

16A and 16B schematically show the configuration of the bonding detection device 350B of the second modification example viewed from the top and the side, respectively. Here, FIG. 16B is a cross-sectional view about the reference line BB in FIG. 16A. In addition, the holder 221 and the upper stage 322 are omitted in FIG. 16A. The holders 221 and 223 are omitted in FIG. 16B. The bonding detection device 350B includes a plurality of electrode pairs 351B to 351E. One of the two electrodes 351b to 351e included in the respective electrode pairs 351B to 351E is provided on the four edges of the lower surface of the upper stage 322, and the other is provided on the four edges of the upper surface of the download stage 332. By detecting the electrostatic characteristics of each electrode pair 351B to 351E, the four edges of the substrates 211 and 213 held by the respective upper stage 322 and the download stage 332 can be used to detect the contact area formed between the substrates 211 and 213 The enlargement process of 215 and the bonding are over.

In addition, the examples shown in FIGS. 15B and 16B show an example in which one electrode pair 351A or a plurality of electrode pairs 351B to 351E are provided on the respective uploading station 322 and the downloading station 332, but when the holders 221, 223 are used Next, one electrode pair 351A or a plurality of electrode pairs 351B-351E may also be provided on the holders 221 and 223.

Above, the present invention has been explained using the embodiments, but the technical scope of the present invention is not limited to the scope described in the above embodiments. Those skilled in the art understand that various changes or improvements can be added to the above-mentioned embodiment. It is clear from the description of the scope of the patent application that the form of adding such changes or improvements may also be included in the technical scope of the present invention.

Please pay attention to the execution order of various processes such as actions, procedures, steps, and stages in the device, system, program, and method shown in the scope of patent application, specification, and drawings, as long as it is not specifically stated as "earlier" in advance , "In advance", etc., or as long as the output of the previous processing is not used in the subsequent processing, it can be implemented in any order. Regarding the scope of patent application, the description, and the flow of action in the drawings, even if the expedient use "first", "second", etc. for explanation, it does not necessarily mean that they must be implemented in this order.

100: Substrate bonding system 110: Frame 120, 130: substrate cassette 140: Conveying device 150: control device 150a: Judgment Department 150b: Control Department 210, 211, 213: substrate 212: underline 214: Groove 215: contact area 216: circuit area 218: Counterpoint Mark 220, 221, 223: Holder 222, 224: Keep the face 230: Laminated substrate 232: Conjugation Wave 300: Fitting device 310: Frame 312: Floor 314: Pillar 316: top plate 322: upload platform 324, 334: Microscope 326, 336: Activation Device 331: X direction drive unit 332: download station 333: Y direction drive unit 336: Activating Device 338: Lifting drive 341: Interferometer 350, 350A, 350B: bonding detection device 351: Electrode 351A～351H: Electrode pair 351a～351h: Electrode 352: Electrode drive device 353, 353a～353e: Detection section 354: selector 355, 356, 357: guide 400: Holder temporary storage box 500: Pre-register

Figure 1 schematically shows the structure of the substrate bonding system. Figure 2 shows the surface structure of the substrate bonded by the substrate bonding system. Figure 3 schematically shows the structure of the laminating device. Fig. 4A schematically shows the structure of the bonding detection device. Fig. 4B schematically shows another configuration of the bonding detection device. Fig. 5A shows an example of the arrangement of electrode pairs. Fig. 5B shows a variation of the configuration of the electrode pair in Fig. 5A. Fig. 6A shows another example of arranging electrode pairs. Fig. 6B shows a variation of the configuration of the electrode pair in Fig. 6A. Fig. 7A schematically shows the cross-sectional structure of the holder for holding the substrate. Fig. 7B schematically shows the cross-sectional structure of another holder for holding the substrate. FIG. 8A shows the state of the substrate in the substrate bonding process (the state where the two substrates are aligned). Fig. 8B shows the state of the substrate in the substrate bonding process (the state in which the contact area is formed). FIG. 8C shows the state of the substrate in the substrate bonding process (the state in which the bonding wave is in progress). Fig. 8D shows the state of the substrate in the substrate bonding process (the state where the bonding is completed). Figure 9A shows the electrode shape and the principle of detecting substrate displacement. Fig. 9B shows the electrode shape and the principle of detecting the displacement of the substrate. Fig. 9C shows an example of the result of substrate displacement detection in the substrate bonding process. FIG. 9D shows another example of the result of substrate displacement detection in the substrate bonding process. Figure 10A shows another principle of electrode shape and substrate displacement detection. Figure 10B shows another principle of electrode shape and substrate displacement detection. FIG. 10C shows an example of the result of detecting the displacement of the substrate in the substrate bonding process. Fig. 11A shows the electrode shape and the principle of substrate displacement detection in a modified example. Fig. 11B shows the electrode shape and the principle of substrate displacement detection of the modified example. Figure 12 shows the flow of the substrate bonding step. FIG. 13A shows one process (carrying in the substrate) of the substrate bonding step in the bonding apparatus. FIG. 13B shows a process (detection of alignment marks) of the substrate bonding step in the bonding device. FIG. 13C shows a process (activation of the substrate surface) of the substrate bonding step in the bonding device. Fig. 13D shows a step (aligning the substrate) of the substrate bonding step in the bonding apparatus. Fig. 13E shows a step (arrangement of electrode pairs) of the substrate bonding step in the bonding device. Fig. 13F shows a step of the substrate bonding step in the bonding device (forming a bonding starting point). Fig. 13G shows one step of the substrate bonding step in the bonding apparatus (carrying out the bonded substrate). Fig. 14A shows a variation of the arrangement of electrodes and the principle of substrate displacement detection. Figure 14B shows a variation of the electrode configuration and the principle of substrate displacement detection. Fig. 15A schematically shows the configuration of the bonding detection device of the first modification. Fig. 15B schematically shows the configuration of the bonding detection device of the first modification. Fig. 16A schematically shows the configuration of the bonding detection device of the second modification. Fig. 16B schematically shows the configuration of the bonding detection device of the second modification.

150: control device

150a: Judgment Department

150b: Control Department

211, 213: substrate

215: contact area

350: Fitting detection device

351A~351H: Electrode pair

351a~351h: Electrode

353a~353e: Detection Department

Claims (20)

A substrate bonding device is for bonding a first substrate and a second substrate, and includes: A pair of electrodes, which are arranged to sandwich at least one of the first substrate and the second substrate; and The detection part detects the electrostatic characteristics between the aforementioned pair of electrodes. The substrate bonding apparatus according to claim 1, wherein the pair of electrodes are arranged in a plane direction of bonding surfaces of the first substrate and the second substrate, sandwiching the first substrate and the second substrate. The substrate bonding device of claim 2, wherein at least one of the pair of electrodes has an electrode surface opposed to an end surface of at least one of the first substrate and the second substrate, The electrode surface has a shape whose width changes along the direction in which the first substrate and the second substrate overlap. The substrate bonding apparatus according to claim 2, wherein at least one of the pair of electrodes is arranged obliquely with respect to the direction intersecting the plane direction. The substrate bonding device of claim 2, wherein the pair of electrodes are arranged on the first substrate and the second substrate opposite to each other in the direction of the surface, sandwiching the contact area between the first substrate and the second substrate The side. The substrate bonding device of claim 5, wherein the detection portion has a guide member that can move the pair of electrodes in the circumferential direction of the first substrate and the second substrate. The substrate bonding device of claim 2, wherein the pair of electrodes sandwich the first substrate separated from the contact area between the first substrate and the second substrate in a first direction parallel to the surface direction And the edges of the second substrate are arranged opposite to each other in a second direction intersecting the first direction. According to the substrate bonding device of claim 7, wherein the detection part has a guide which can move the pair of electrodes in the first direction. A substrate bonding device according to claim 2, which includes: a pair of first electrodes which are disposed opposite to each other on the first substrate and the second substrate, sandwiching the contact area between the first substrate and the second substrate The side of the substrate; and a pair of second electrodes, which are sandwiched between the edges of the first substrate and the second substrate and are arranged opposite to each other on the sides of the first substrate and the second substrate; The pair of first electrodes have larger electrode surfaces than the pair of second electrodes. Such as the substrate bonding device of claim 1, which is provided with a plurality of electrode pairs, which includes the aforementioned pair of electrodes, The detection unit detects the electrostatic characteristics of each of the plurality of electrode pairs using AC signals of different frequencies. The substrate bonding device of claim 1, which is further provided with a selector, which selects the aforementioned pair of electrodes from a plurality of electrode pairs to recombine. The substrate bonding device according to claim 1, which includes an electrode driving device for retracting the pair of electrodes from the sides of the first substrate and the second substrate. For example, the substrate bonding device of claim 1 further includes a judgment unit that judges the state of the contact area between the first substrate and the second substrate based on the detection result of the electrostatic characteristic. The substrate bonding apparatus of claim 1, which further includes a control unit that controls the slope of at least one of the first substrate and the second substrate based on the detection result of the electrostatic characteristic. The substrate bonding device according to any one of claims 1 to 13, wherein at least one of the pair of electrodes is arranged on the back side of the first substrate after the first substrate is bonded to the second substrate, Or, it is arranged at a position where the first substrate is bonded to the second substrate and faces the first substrate, and before the first substrate is bonded to the second substrate, the first substrate is not opposed to the first substrate. A substrate bonding method is a substrate bonding method of bonding a first substrate and a second substrate, and includes: A stage of forming a contact area between the first substrate and the second substrate, each part of which is in contact with each other; The stage of expanding the aforementioned contact area; and The stage of detecting the electrostatic characteristics between a pair of electrodes arranged sandwiching at least one of the first substrate and the second substrate. The substrate bonding method according to claim 16, wherein the pair of electrodes are arranged by sandwiching the first substrate and the second substrate in the plane direction of the bonding surfaces of the first substrate and the second substrate. The substrate bonding method of claim 16, wherein before the stage of arranging the pair of electrodes, a stage of detecting the respective alignment marks of the first substrate and the second substrate is further provided. The substrate bonding method of claim 16, which further includes a stage of judging the state of the contact area according to the detection result of the electrostatic characteristic. The substrate bonding method according to any one of claims 16 to 19, which further includes a stage of controlling the slope of at least one of the first substrate and the second substrate according to the detection result of the electrostatic characteristic.

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