JP2012182465A - Joining apparatus, joining method, and manufacturing method - Google Patents

Abstract

PROBLEM TO BE SOLVED: To efficiently and safely join substrates in a uniform condition over the entire surfaces.SOLUTION: A joining apparatus joins a pair of substrates and includes: a position control part which detects a position of one substrate and regulates the movements of the one substrate in a direction that the one substrate moves close to the other substrate and in a direction that the one substrate moves away from the other substrate based on the detected position; a proximity detection part which detects that the pair of substrates are positioned close to each other with a clearance, which is smaller than a clearance having a predetermined dimension, formed therebetween or the pair of substrates are in contact with each other; and a pressure control part which detects a pressure acting between the pair of substrates after the proximity detection part detects the proximity or the contact of the pair of substrates and pressurizes the one substrate toward the other substrate until the pressure reaches a given target pressure.

Description

  The present invention relates to a joining apparatus and a manufacturing method. More specifically, the present invention relates to a bonding apparatus used when a substrate such as a wafer is bonded and a method for manufacturing a bonded substrate using the bonding apparatus.

  One technique for improving the effective mounting density of semiconductor devices is a structure in which a plurality of chips are stacked. In particular, a laminated chip semiconductor module in which chips before packaging are stacked not only improves the mounting density of chips on a mounting substrate, but also realizes high-speed processing by shortening the wiring between chips.

  In the case of manufacturing a laminated chip semiconductor module, productivity is higher in the procedure of cutting chips after bonding in wafer units than in bonding in chip units. However, when bonding a wafer having a larger area than that of a chip, it is required that the whole wafer is pressed and bonded under uniform conditions. Therefore, there is a need for a technique that eliminates the slight inclination of the substrates to be joined, the pressure distribution, and the like.

The following Patent Document 1 describes a bonding apparatus that is provided with a copying mechanism having a spherical sliding member to autonomously level the substrate. Patent Document 2 below describes a bonding apparatus that includes a mounting table supported via cylindrical surfaces whose axes intersect with each other and autonomously leveles the mounted substrate. Further, Patent Document 3 below describes a substrate holding device that includes a stage supported by a plurality of individually operating actuators and adjusts the tilt of a semiconductor substrate.
Japanese Patent Laid-Open No. 03-179757 Japanese Patent Laid-Open No. 05-090341 JP 2007-035669 A

  However, even when a bonding apparatus having a function of adjusting the inclination or the like of the bonding target is used, it takes time to work to adjust the inclination and make the pressure distribution uniform.

  In order to solve the above problems, a first embodiment of the present invention is a bonding apparatus for bonding a pair of substrates, wherein the position of one substrate is detected, and one substrate is detected based on the detected position. A position control unit that controls movement of one substrate in a direction close to the substrate and a direction in which one substrate separates from the other substrate, and a pair of substrates at intervals of a predetermined size or less. Proximity detection unit that detects that they are close to each other or a pair of substrates are in contact with each other, and the proximity detection unit acts between the pair of substrates after detecting the proximity or contact of the pair of substrates And a pressure control unit that pressurizes one substrate toward the other substrate until the pressure reaches a given target pressure.

  According to a second aspect of the present invention, there is provided a bonded substrate manufacturing method for manufacturing a bonded substrate by bonding a pair of substrates, the position of one substrate being detected, and the position of the one substrate being a target position. Until one of the substrates is moved closer to the other substrate, the pair of substrates is detected to be sufficiently close or in contact with each other, and the proximity or contact between the pair of substrates is detected. After detection, a manufacturing method is provided in which a pressure acting between a pair of substrates is detected and one substrate is pressed toward the other substrate until the pressure reaches a given target pressure.

  The above summary of the invention does not enumerate all the necessary features of the present invention, and sub-combinations of these feature groups can also be the invention.

  Hereinafter, the present invention will be described through embodiments of the invention, but the following embodiments do not limit the invention according to the claims. In addition, not all the combinations of features described in the embodiments are essential for the solution of the invention.

  FIG. 1 is a cross-sectional view schematically showing the structure of a bonding apparatus 100 used when the wafers 162 and 164 are stacked with a uniform pressure. The bonding apparatus 100 includes a pressure unit 120, a pressure stage 130, a pressure receiving stage 140, and a pressure detection unit 150 disposed inside the frame body 110.

  The frame 110 includes a top plate 112 and a bottom plate 116 that are parallel to each other and a plurality of columns 114 that couple the top plate 112 and the bottom plate 116. The top plate 112, the support column 114, and the bottom plate 116 are each formed of a material having high rigidity, and deformation does not occur even when a reaction force of pressure applied to the wafers 162 and 164 in bonding described later is applied.

  On the inner side of the frame 110, the pressure unit 120 is disposed on the bottom plate 116. The pressure unit 120 includes a cylinder 122 fixed to the upper surface of the bottom plate 116 and a plunger 124 disposed inside the cylinder 122. The plunger 124 is driven by a fluid circuit (not shown), a cam, a train wheel, etc., and moves up and down in a direction perpendicular to the bottom plate 116 indicated by an arrow Z in the drawing.

  A pressure stage 130 is mounted on the upper end of the plunger 124. The pressure stage 130 includes a horizontal plate-like support portion 132 coupled to the upper end of the plunger 124, and a plate-like substrate holding portion 134 parallel to the support portion 132. The support part 132 has a spherical seat 131 formed in an upper opening at the center of the upper surface. On the other hand, the substrate holding part 134 has a spherical part 133 projecting downward at the center of the lower surface.

  The spherical seat 131 and the spherical portion 133 are fitted with shapes and dimensions complementary to each other. Thereby, the substrate holding part 134 can change the inclination angle on the support part 132. Further, even when the inclination angle of the substrate holding part 134 changes on the support part 132, the force by which the plunger 124 pushes up the support part 132 is transmitted to the substrate holding part 134. Furthermore, the support part 132 regulates the displacement of the substrate holding part 134 from below, and prevents the substrate holding part 134 from being excessively inclined.

  The substrate holding unit 134 adsorbs the wafer 162 on the upper surface by electrostatic adsorption, negative pressure adsorption or the like. As a result, the wafer 162 adsorbed on the substrate holding part 134 swings together with the substrate holding part 134, while the movement or dropping from the substrate holding part 134 is suppressed.

  The pressure receiving stage 140 includes a substrate holding part 142 and a plurality of suspension parts 144. The suspension part 144 is suspended from the lower surface of the top plate 112. The substrate holding part 142 is supported from below in the vicinity of the lower end of the suspension part 144, and is disposed to face the pressure stage 130. The substrate holding unit 142 also has an adsorption mechanism such as electrostatic adsorption or negative pressure adsorption, and adsorbs the wafer 164 to the lower surface.

  The substrate holding part 142 is supported by the suspension part 144 from below, but the upward movement is not restricted. However, a plurality of load cells 152, 154, 156 are sandwiched between the top plate 112 and the substrate holder 142. The plurality of load cells 152, 154 and 156 form a part of the pressure detection unit 150 to regulate the upward movement of the substrate holding unit 142 and detect the pressure applied upward to the substrate holding unit 142. .

  The state shown in FIG. 1 corresponds to an initial state among the operations of the bonding apparatus 100 described later. In this state, the support column 114 of the pressurizing unit 120 is drawn into the cylinder 122, and the pressurizing stage 130 is in a lowered state. Therefore, there is a wide gap between the pressure stage 130 and the pressure receiving stage 140.

  Of the pair of wafers 162 and 164 to be bonded, one wafer 162 is inserted into the gap from the side and placed on the pressure stage 130. The other wafer 164 is inserted in the same manner and held on the pressure receiving stage 140 so as to face the wafer 162. A thermosetting resin as an adhesive resin is applied to at least one of the bonding surfaces of the wafers 162 and 164 facing each other. The wafers 162 and 164 are aligned with each other in a plane orthogonal to the Z direction.

  FIG. 2 is a perspective view showing a layout of the load cells 152, 154, 156 in the pressure detection unit 150. The pressure detection unit 150 includes a plurality of load cells 152, 154 and 156 fixed to the lower surface of the top plate 112. Each of the load cells 152, 154, and 156 outputs an electrical signal proportional to the pressure when a pressure is applied upward from the top plate 112. Accordingly, when the wafer 162 comes into contact with the wafer 164 due to the rise of the pressure stage 130, any of the load cells 152, 154, 156 detects the pressure generated by the contact.

  In addition, the load cells 152, 154, and 156 are arranged at different positions on the lower surface of the top plate 112. Therefore, the pressure distribution in the plane parallel to the top plate 112 can also be detected. Here, as already described, the pressure unit 120 pushes up the pressure stage 130 by the plunger 124. Therefore, when the pressure distribution is detected by the pressure detection unit 150, it means that the pressure stage 130 has a different inclination with respect to the pressure receiving stage 140. In view of the function of the pressure detector 150, the number of load cells 152, 154, and 156 is not limited to three, but is preferably three or more.

  FIG. 3 is a perspective view showing the structure of the position detection mechanism 200 used in the joining apparatus 100. The position detection mechanism 200 includes a pair of imaging units 212 and 222 and a pair of illumination units 214 and 224.

  One imaging unit 212 is arranged to face one illumination unit 214 in a plane parallel to the bonding surfaces of the wafers 162 and 164. The imaging unit 212 sends out the captured image to the outside via the connector 216. The illumination unit 214 receives power supply via the power cable 218. Similarly, the other imaging unit 222 is disposed to face one illumination unit 224 in a plane parallel to the bonding surfaces of the wafers 162 and 164. The imaging unit 222 also sends out the captured image to the outside via the connector 226. The illumination unit 224 receives power supply via the power cable 228. For convenience of explanation, in the following description, the arrangement direction of the imaging unit 212 and the illumination unit 214 is described as the X direction, and the arrangement direction of the imaging unit 222 and the illumination unit 224 is described as the Y direction.

  FIG. 4 is a side view of the position detection mechanism 200. The illumination light emitted from the illumination unit 214 propagates through the gaps between the wafers 162 and 164 and is received by the imaging unit 212. Also, the illumination light emitted from the illumination unit 224 propagates through the gaps between the wafers 162 and 164 and is received by the imaging unit 222. In other words, each of the imaging units 212 and 222 captures images of the wafers 162 and 164 that block the illumination light emitted from the illumination units 214 and 224. Accordingly, the positions of the wafers 162 and 164 can be detected from the images captured by the imaging units 212 and 222.

  Further, for example, when the wafer 162 is rotated and tilted about the axis in the Y direction, an image of the tilted wafer 164 is captured by the imaging unit 212. Thereby, the inclination of the wafer 162 that may occur when the pressure stage 130 moves can be detected.

  Further, when the wafers 162 and 164 come into contact with each other, the illumination light is blocked between the wafers 162 and 164. Therefore, the contact of the wafers 162 and 164 can be detected from an image captured by any of the imaging units 212 and 222.

  However, the resolution of the imaging units 212 and 222 depends on the resolution of the optical system and the imaging device. Therefore, when the gap between the wafers 162 and 164 is smaller than the resolution of the imaging units 212 and 222, the timing at which the wafers 162 and 164 are in contact with the timing at which contact is detected may be different. However, since the gap that cannot be detected by the imaging units 212 and 222 is very narrow, if the gap between the wafers 162 and 164 cannot be imaged, it can be considered that the wafers 162 and 164 are in contact.

  3 and 4 is merely an example of the position detection mechanism 200, and the same function can be formed with other structures. For example, by using an interferometer instead of the imaging units 212 and 222, the position detection mechanism 200 with higher resolution can be formed. On the other hand, a simpler position detection mechanism 200 can be formed using a linear scale. These various structures can be appropriately selected by those skilled in the art according to the specifications of the target bonded wafer or bonded substrate.

  FIG. 5 is a diagram schematically showing the structure of the control system 300 of the bonding apparatus 100. The control system 300 includes a pressure control unit 310, a position control unit 320, a proximity detection unit 330, and a control switching unit 340 provided for the bonding apparatus 100 including the position detection mechanism 200.

  The bonding apparatus 100 holds the wafers 162 and 164 on the substrate holding portions 134 and 142 of the pressure stage 130 and the pressure receiving stage 140, respectively. The position detection mechanism 200 is disposed on the side of the wafers 162 and 164 held by the bonding apparatus 100.

  The pressure controller 310 refers to the pressure detected by the pressure detector 150 and generates a control signal for controlling the driving amount of the pressurizer 120. Therefore, under the control of the pressure control unit 310, the pressurization unit 120 can be operated until the pressure detected by the pressure detection unit 150 reaches a given target pressure.

  The position control unit 320 includes a target position setting unit 322 and a target position update unit 324. The target position setting unit 322 refers to the positions of the wafers 162 and 164 detected by the position detection mechanism 200 and sets the target position closer to the wafer 164 than the position of the wafer 162 detected by the position detection mechanism 200. To do. The position control unit 320 operates the pressure unit 120 to raise the wafer 162 until the wafer 162 reaches the target position.

  When the wafer 162 that has already reached the target position is not yet in contact with the wafer 164, the target position update unit 324 sets a new target position at a position closer to the wafer 164 than the already set target position. . As a result, the position controller 320 continues to operate the pressure unit 120 until the wafer 162 reaches the updated target position. Thus, until the wafers 162 and 164 come into contact with each other, that is, until the position where the wafer 162 contacts the wafer 164 and the target position coincide with each other, the target position update unit 324 updates the target position, and the position control unit 320 adds the target position. The pressure unit 120 is operated to raise the wafer 162.

  The proximity detection unit 330 refers to the output of the position detection mechanism 200 via the position control unit 320 and detects contact of the wafers 162 and 164. Specifically, the proximity detection unit 330 determines the distance between the central portions of the wafers 162 and 164 and the inclination angle of the wafer 162 with respect to the wafer 164 based on images output from the imaging units 212 and 222 of the position detection mechanism 200. And the distance between the portion of the edge of the wafer 162 closest to the wafer 164 and the wafer 164 is calculated from the detected distance and inclination angle, and the calculated distance is less than or equal to a predetermined size. If the distance is not larger than a predetermined size, it is determined that the wafers 162 and 164 are close to each other. When the proximity detection unit 330 detects proximity, the proximity detection unit 330 notifies the control switching unit 340 to that effect. However, “proximity” detected by the proximity detection unit 330 is, for example, a case where the interval between the wafers 162 and 164 becomes narrower than the resolution of the position detection mechanism 200. In this case, the case where the wafers 162 and 164 are in contact with each other is also included.

  For example, the resolution when a CCD camera is used as the imaging units 212 and 222 of the position detection mechanism 200 is about 0.6 μm. In addition, the surfaces of the wafers 162 and 164 to be bonded have undulations corresponding to TTV (total film thickness dispersibility) that has been known in advance. Therefore, when the distance between the wafers 162 and 164 approaches the detection limit of the position detection mechanism 200 considering these factors, it is preferable to reduce the speed at which the wafer 162 is raised.

  Specifically, an interval slightly larger than the resolution limit of the imaging units 212 and 222 is set as a threshold value, and when the interval between the wafers 162 and 164 becomes narrower than the threshold value, the position control unit 320 Thus, the rising speed of the wafer 162 by the pressurizing unit 120 may be decreased. Thereby, the impact which arises when the wafers 162 and 164 contact can be relieved.

  The control switching unit 340 selectively enables one of the control signals output from the pressure control unit 310 and the position control unit 320 to control the operation amount of the pressurizing unit 120. The timing at which the control signal is switched depends on the notification received from the proximity detection unit 330 by the control switching unit 340. Thereby, the control switching unit 340 switches the operation control of the pressurizing unit 120 from the control by the position control unit 320 to the control by the pressure control unit 310 after the proximity detection unit 330 detects the contact of the wafers 162 and 164.

  FIG. 6 is a cross-sectional view showing a state of the bonding apparatus 100 in the next operation stage. In this state, the pressure unit 120 operates and the pressure stage 130 is raised. Thereby, the wafers 162 and 164 are in contact with each other.

  However, in this example, the wafer 162 is inclined together with the pressure stage 130. For this reason, the wafers 162 and 164 are in contact with each other at a part of the edge and are not in close contact with each other. Note that even if the wafer 162 is adjusted to be horizontal when the wafer 162 is placed on the pressure stage 130, there may be a tilt when the pressure unit 120 is operated.

  FIG. 7 is a cross-sectional view showing a state of the bonding apparatus 100 in the next operation stage. In this state, the pressure stage 130 is further raised from the position shown in FIG. 6, and the wafers 162 and 164 are in close contact with each other. Therefore, the pressure stage 130 does not move upward.

  However, the achieved target pressure is maintained until the state of the adhesive resin sandwiched between the wafers 162 and 164 is stabilized. For this reason, even after the raising of the pressurizing stage 130 is finished, the operation of the pressurizing unit 120 that maintains the target pressure is continued.

  The wafers 162 and 164 bonded in this manner are mounted with a holder or the like that maintains the bonded state, and sent to the next process as a semi-finished product of bonded wafers. In the next step, the wafers 162 and 164 are heated while maintaining the bonded state by pressurization, whereby the adhesive resin is cured and the bonded wafer is completed. Note that a heating device may be incorporated in the substrate holding portions 134 and 142 of the bonding apparatus 100 so that the adhesive resin can be cured following the bonding.

  FIG. 8 is a flowchart showing the procedure of the bonding process using the bonding apparatus 100. At the beginning of the bonding of the wafers 162 and 164 by the bonding apparatus 100, the control switching unit 340 operates the pressure unit 120 under the control of the position control unit 320. Thereby, the pressurization part 120 drives the pressurization stage 130 by position control.

  That is, the position control unit 320 detects the positions of the wafers 162 and 164 with reference to the images detected by the imaging units 212 and 222. The target position setting unit 322 refers to the detected positions of the wafers 162 and 164, and the position of the wafer 164 held by the pressure receiving stage 140 with respect to the current position of the wafer 162 mounted on the pressure stage 130. A target position closer to is set (step S101). The position control unit 320 operates the pressure unit 120 to move the pressure stage 130 to the set target position.

  When the wafer 164 reaches the target position (step S103), in the position control unit 320, the target position update unit 324 refers to the output of the proximity detection unit 330. If the wafers 162 and 164 are still separated (step S104; NO), the target position update unit 324 causes the target position setting unit 322 to set a new target position. The new target position is closer to the wafer 164 than the position of the wafer 162 at that time.

  In the position control described above, the position control unit 320 preferably decreases the speed of the proximity movement as the pair of wafers 162 and 164 approach each other. This prevents a large impact from occurring at the moment when the wafers 162 and 164 come into contact with each other.

  On the other hand, when the distance between the wafer 162 and the wafer 164 is close to the resolution limit of the imaging units 212 and 222 (step S104; YES), the proximity detection unit 330 notifies that and the control switching unit 340 Enables the pressure control unit 310 (step S105). Thereby, thereafter, the pressurizing unit 120 operates under pressure control. Since the position control becomes invalid after the pressure control unit 310 becomes valid, the operation of the position control unit 320 may be stopped.

  The pressure control unit 310 uses the pressure that the pressurization unit 120 is required to apply to the wafer 162 when bonding the wafers 162 and 164 as a target pressure, and refers to the pressure detected by the pressure detection unit 150 while referring to the pressure. 120 is operated to pressurize the wafer 162 (step S106). In other words, when the detected pressure does not reach the target pressure (step S107; NO), the pressurizing unit 120 is continuously operated.

  Here, the pressurizing unit 120 does not apply the pressure required for bonding from the beginning, but the pressure control unit 310 refers to the output of the pressure detecting unit 150 to determine the pressing force applied to the wafers 162 and 164. When the pressure is small, the degree of increase in the pressing force may be reduced, and the operation of the pressurizing unit 120 may be controlled so that the pressing force increases greatly as the pressing force increases. By controlling the pressure increase amount as described above, when the wafers 162 and 164 are not in close contact as shown in FIG. 6, it is possible to prevent a large pressing force from being applied to a part of the wafers 162 and 164 from being applied. The

  When the target pressure is detected by the pressure detection unit 150 (step S107; NO), the pressure control unit 310 causes the pressure unit 120 to adjust the pressure until the state of the adhesive resin sandwiched between the wafers 162 and 164 is stabilized. Control is performed so as to maintain (step S108).

  In this way, a manufacturing method for manufacturing a bonded wafer by bonding a pair of wafers 162 and 164, the position of one wafer 164 is detected, and the wafers until the position of the other wafer 162 reaches the target position. 162 is moved close to the other wafer 164 to detect that the pair of wafers 162 and 164 are sufficiently close or in contact with each other, and are sufficiently close to or in contact with each other. If it is detected that the pressure is applied, the pressure acting between the pair of wafers 162 and 164 is detected, and one wafer 162 is moved to the other wafer 164 until the pressure reaches a given target pressure. A manufacturing method of pressing toward the surface is executed.

  FIG. 9 is a partial flowchart showing a procedure that can be executed in place of step S106 in the procedure shown in FIG. For convenience of explanation, step S105 and step S107 shown in FIG. 8 are described in duplicate, but the steps before and after are the same as those in FIG.

  As already described, when the proximity detection unit 330 detects contact or proximity of the wafers 162 and 164, the control switching unit 340 switches the control of the pressurization unit 120 to the pressure control unit 310 (step S105). Thereby, the pressurization part 120 drives the pressurization stage 130 under pressure control.

  However, as shown in FIG. 6, at this stage, the wafers 162 and 164 are not necessarily in close contact with each other. When a large pressure required for bonding is applied, the gap between the wafers 162 and 164 is rapidly closed. In some cases, an impact is applied to the wafers 162 and 164. Therefore, at the beginning of switching to the pressure control, the target pressure of the pressure control unit 310 is set to be small and the pressurization unit 120 is operated (step S201). This reduces the impact that can occur on the wafers 162 and 164.

  Subsequently, the pressure detected by each of the plurality of load cells 152, 154, and 156 forming the pressure detector 150 is compared. When the detected pressure is no longer biased (step S202; YES), the pressure control unit 310 switches the target pressure to a large pressure required for bonding and continues the pressure control (step S203).

  By introducing such steps (steps S201 to S203), the impact that can be applied to the wafers 162 and 164 can be reduced, and damage to the wafers 162 and 164 can be prevented. Note that, during a period in which the pressures detected by the load cells 152, 154, and 156 are different from each other (step S202; NO), the pressure control unit 310 controls the operation of the pressurizing unit 120 with a small target pressure.

  Such a series of controlled bonding methods include bonding of dissimilar substrates such as Si single crystal bonding, substrates of other materials such as compound semiconductor substrates, or combinations of Si single crystal substrates and compound semiconductor substrates. It can also be applied to Further, the present invention can also be applied to a case where a laminated chip or the like is manufactured by joining substrates on which elements, circuits, or the like are already formed.

  In the above embodiment, the proximity detection unit 330 detects the proximity of the wafers 162 and 164 with reference to the output of the position detection mechanism 200. However, for example, the proximity detector 330 that detects the proximity of the wafers 162 and 164 by detecting the contact pressure of the wafers 162 and 164 with reference to the output of the pressure detector 150 may be used.

  In this case, the proximity detector 330 can detect the proximity of the wafers 162 and 164 regardless of the resolution of the imaging units 212 and 222. However, in order to reduce the impact when the wafers 162 and 164 come into contact with each other, the change in the gap between the wafers 162 and 164 is observed by the imaging units 212 and 222. It is also preferable to reduce the rising speed.

  FIG. 10 is a cross-sectional view schematically showing the structure of a bonding apparatus 100 according to another embodiment. In addition, the joining apparatus 100 has the same structure as the joining apparatus 100 shown in FIG. 1 except the part demonstrated below. Therefore, the same components are assigned the same reference numerals, and duplicate descriptions are omitted.

  In this bonding apparatus 100, the substrate holding part 134 is supported from the support part 132 via a plurality of actuators 135 instead of the spherical seat 131 and the spherical part 133. In addition to the pair of actuators 135 shown in the figure, the actuator 135 is also arranged forward and backward with respect to the paper surface.

  Each of these actuators 135 operates independently of each other under the control of the position control unit 320 and the pressure control unit 310. With such a structure, the tilt of the substrate holding part 134 can be arbitrarily changed by appropriately operating the actuator 135. The inclination of the substrate holding part 134 is changed while monitoring images obtained from the imaging parts 212 and 222 arranged as shown in FIG.

  Note that the imaging range M of the imaging units 212 and 222 in the bonding apparatus 100 is indicated by a dotted line in the drawing. As illustrated, when the wafer 162 is initially placed on the substrate holder 134, the wafer 162 is deviated from the angle of view of the imaging units 212 and 222. On the other hand, the wafer 164 is in the imaging range M from the beginning.

  FIG. 11 is a cross-sectional view illustrating a state in which the bonding apparatus 100 starts to operate. When the pressing unit 120 operates and the support unit 132 and the substrate holding unit 134 rise, the wafer 162 enters the imaging range M before long. Accordingly, the wafers 162 and 164 can be bonded while monitoring the images of the imaging units 212 and 222.

  In other words, the wafers 162 and 164 do not contact each other until the wafer 162 is imaged by the imaging units 212 and 222. Therefore, the support unit 132 and the substrate holding unit 134 may be raised at high speed until the wafer 162 is imaged by the imaging units 212 and 222.

  On the other hand, when the wafer 162 starts to be imaged by the imaging units 212 and 222, it is preferable to reduce the ascending speed of the support unit 132 and the substrate holding unit 134. Accordingly, the operation of the bonding apparatus 100 can be reliably controlled, and the wafers 162 and 164 can be prevented from inadvertently colliding with each other.

  FIG. 12 is a diagram illustrating the joining operation performed while monitoring the images captured by the imaging units 212 and 222 in the order of the work stages. As shown in FIG. 12A, when the wafer 162 enters the imaging range M, monitoring by an image is started. Here, as shown in FIG. 12B, when the wafer 162 is tilted, the actuator 135 is operated under the control of the position control unit 320 based on the images captured by the imaging units 212 and 222. Wafer 162 is leveled. Thereby, since the movement of the wafer 162 to the wafer 164 and the tilting of the wafer 162 can be performed at the same time, the wafer 162 is tilted as compared with the case where the tilting of the wafer 162 is performed with the movement of the wafer 162 once stopped, for example. It is possible to further shorten the time from the start of rising until the wafer 164 is approached.

  After the wafer 162 becomes horizontal, the wafer 162 is continuously raised under the control of the position control unit 320 as shown in FIG. Eventually, as shown in FIG. 12D, when the wafer 162 approaches the wafer 164 to the limit of the resolution of the imaging units 212 and 222, the control of the pressurizing unit 120 is switched to the pressure control unit 310. In this way, the wafer 162 and the wafer 164 can be bonded.

  In addition, even after the control of the pressurizing unit 120 is switched to the pressure control unit 310, the operation of the actuator 135 may be controlled with reference to the pressure detected by the load cells 152, 154, and 156. Thereby, when a pressure distribution is generated in the surface of the wafer 162, the pressure distribution is compensated, and the wafers 162 and 164 can be bonded uniformly over the entire surface.

  In the example shown in FIGS. 10 to 12, the support unit 132 and the substrate holding unit 134 are held when the wafer 162 enters the imaging range M of the imaging units 212 and 222 after the support unit 132 and the substrate holding unit 134 are raised at high speed. Although an example in which the rising speed of the part 134 is reduced is shown, instead, the wafer 162 enters the imaging range M of the imaging parts 212 and 222 after the support part 132 and the substrate holding part 134 are raised at high speed. Then, under the control of the position control unit 320, the actuator is operated so that the wafer 162 is parallel to the wafer 164, and at the same time, the wafer 162 is moved at a high speed without reducing the ascending speed of the support unit 132 and the substrate holding unit 134. After the resolution of the imaging units 212 and 222 reaches the limit, the control of the pressurizing unit 120 is switched to the pressure control unit 310 and the support unit 132 The rising speed of the fine substrate holding portion 134 can be reduced.

  In this case, since the time from when the wafer 162 starts to rise until the wafer 162 approaches the wafer 164 can be further shortened, the time spent to join the pair of wafers 162 and 164 to each other can be more reliably reduced. Can do.

  In the example shown in FIGS. 10 to 12 and the modification described above, the control of the pressurizing unit 120 is switched to the pressure control unit 310 in the state shown in FIG. 12D, and then the support unit 132 and the substrate holding unit 134 are raised. The operation of the pressurizing unit 120 can be controlled by the pressure control unit 310 so as to further reduce the speed. In this case, it is possible to more reliably prevent the wafers 162 and 164 from being damaged by the force acting on the wafer 164 from the wafer 162.

  In the example shown in FIGS. 10 to 12, the substrate holding part 134 is supported by the support part 132 via a plurality of actuators 135 instead of the spherical seat 131 and the spherical part 133. Instead of this, the substrate holding part 134 can be supported by the support part 132 via a plurality of actuators 135 in addition to the spherical seat 131 and the spherical part 133.

  In this embodiment, an example in which a single wafer 162, 164 is overlapped with each other is shown. Instead, for example, a stacked body formed by bonding a plurality of wafers to each other and a wafer are bonded to each other. Therefore, the bonding apparatus 100 according to the present invention can be used, and the bonding apparatus 100 according to the present invention can be used to superimpose the laminated bodies on each other.

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

2 is a cross-sectional view schematically showing the structure of the bonding apparatus 100. FIG. FIG. 4 is a diagram illustrating a layout of load cells 152, 154, and 156 in a pressure detection unit 150. 2 is a perspective view schematically showing the structure of a position detection mechanism 200. FIG. 3 is a side view of a position detection mechanism 200. FIG. FIG. 3 is a diagram schematically showing the structure of a control system 300 of the bonding apparatus 100. It is sectional drawing which shows the state of the joining apparatus 100 in one operation | movement stage. It is sectional drawing which shows the state of the joining apparatus 100 in another operation | movement stage. 4 is a flowchart illustrating a procedure of a bonding process using the bonding apparatus 100. FIG. 9 is a partial flowchart showing a control procedure that can be executed instead of a part of the procedure shown in FIG. 8. It is sectional drawing which shows typically the structure of the joining apparatus 100 which concerns on another Example. It is sectional drawing which shows the state which the joining apparatus 100 began to operate | move. It is a figure which shows the joining operation | work using the joining apparatus 100 later on in steps.

  DESCRIPTION OF SYMBOLS 100 Joining device, 110 Frame body, 112 Top plate, 114 Support | pillar, 116 Bottom plate, 120 Pressurization part, 122 Cylinder, 124 Plunger, 130 Pressure stage, 131 Spherical seat, 132 Support part, 133 Spherical part, 134, 142 Substrate Holding unit, 135 Actuator, 140 Pressure receiving stage, 144 Suspension unit, 150 Pressure detection unit, 152, 154, 156 Load cell, 162, 164 Wafer, 200 Position detection mechanism, 212, 222 Imaging unit, 214, 224 Illumination unit, 216, 226 connector, 218, 228 power cable, 300 control system, 310 pressure control unit, 320 position control unit, 322 target position setting unit, 324 target position update unit, 330 proximity detection unit, 340 control switching unit

Claims (8)

A joining device for joining a pair of substrates,
The position of one substrate is detected, and based on the detected position, the one substrate in a direction in which the one substrate is close to the other substrate and a direction in which the one substrate is separated from the other substrate. A position control unit for controlling movement;
A proximity detection unit that detects that the pair of substrates are close to each other at an interval of a predetermined size or less, or that the pair of substrates are in contact with each other;
After the proximity detector detects the proximity or contact of the pair of substrates, the pressure acting between the pair of substrates is detected, and the one substrate is moved until the pressure reaches a given target pressure. A pressure control unit that pressurizes the other substrate,
The position controller is
A target position setting unit that sets a target position based on the detected position of the one substrate;
A target position update unit that updates the target position to a position closer to the other substrate than the previously set target position until the proximity detection unit detects the proximity or contact of the pair of substrates; And
The position control unit decreases the moving speed of the proximity as the distance between the pair of substrates decreases,
The position control unit is a bonding apparatus that decelerates the moving speed of the one substrate toward the other substrate when the proximity detection unit detects the proximity or contact of the pair of substrates.   The bonding apparatus according to claim 1, wherein the pressure control unit decreases the amount of pressure increase as the pressure decreases. The bonding apparatus further includes a substrate holding unit that holds the other substrate,
The pressure control unit includes a plurality of pressure detection units that are arranged in the substrate holding unit and measure pressures received by the other substrate at three or more different positions in a plane facing the other substrate. The joining apparatus according to 1 or 2.   The proximity detection unit detects a distance between the center portions of the pair of substrates and an inclination angle of the one substrate with respect to the other substrate, and an edge portion of the one substrate from the detected distance and inclination angle The distance between the portion closest to the other substrate and the other substrate is calculated, and it is detected whether the calculated size of the distance is equal to or smaller than a predetermined size. 4. The bonding apparatus according to claim 1, wherein the pair of substrates is determined to be close to each other when the size is equal to or less than the size of the substrate.   The image sensor further includes an imaging unit that images the pair of substrates, and the proximity detection unit detects that the pair of substrates are close to or in contact with each other when an interval between the pair of substrates reaches a resolution limit of the imaging unit. The pressure control unit determines that the movement speed of the one substrate before the resolution of the imaging unit reaches the limit after the interval between the pair of substrates reaches the limit of the resolution of the imaging unit. The bonding apparatus according to any one of claims 1 to 4, wherein the movement of the one substrate is controlled so as to be slower than the velocity of the substrate.   The imaging unit is arranged so that the other substrate is within the imaging range, and the position control unit is configured such that when the one substrate enters the imaging range of the imaging unit, the one substrate The bonding apparatus according to claim 5, wherein the movement speed of the one substrate is controlled to be slower than the speed of the one substrate before the one substrate enters the imaging range.   An actuator that operates at least under the control of the position control unit to tilt the one substrate is further provided, the position control unit until the proximity detection unit detects the proximity or contact of the pair of substrates. 7. The bonding apparatus according to claim 1, wherein the movement of the substrate is controlled and the operation of the actuator is controlled so that the one substrate is parallel to the other substrate. 8. A method of manufacturing a bonded substrate by bonding a pair of substrates to manufacture a bonded substrate,
Detecting the position of one substrate and moving the one substrate closer to the other substrate until the position of the one substrate reaches a target position,
Detecting that the pair of substrates are sufficiently close or in contact with each other;
After detecting the proximity or contact of the pair of substrates, the pressure acting between the pair of substrates is detected, and the one substrate is moved to the other substrate until the pressure reaches a given target pressure. A manufacturing method in which pressure is applied toward
In the proximity movement, the target position is set based on the detected position of the one substrate, and the target position is set to be more than the already set target position until the proximity or contact of the pair of substrates is detected. Update to a position close to the other board,
As the distance between the pair of substrates decreases, the moving speed of the proximity decreases.
A manufacturing method for reducing a moving speed of the one substrate toward the other substrate when proximity or contact of the pair of substrates is detected.

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