Connecting device

Abstract

In the joining device of the present invention, an adsorption surface is formed on the front end face of the pressing part, which holds the first workpiece through the back of the sheet by adsorbing it; and a retraction surface that retracts from the adsorption surface around the adsorption surface. The peripheral holding part is a portion that holds the peripheral area of ​​the area where the first workpiece is attached to the sheet, and is itself annular, having an annular adsorption surface that adsorbs and holds the entire peripheral area. The pressing part and the peripheral holding part have a sealing structure that seals the outer periphery of the retraction surface with the inner periphery of the peripheral holding part. This forms a sealed space between the adsorption surfaces when the sheet is adsorbed onto the adsorption surface of the pressing part and the adsorption surface of the peripheral holding part. Furthermore, the joining device reduces the internal pressure of the sealed space when the first workpiece is pressed.

Description

[Technical Field]

[0001] This invention relates to a bonding technology for wafers and substrates. [Previous Technology]

[0002] Patent Document 1 discloses a technique in which a wafer (LSI or IC, etc.) is attached to the surface of an elastically deformable sheet (such as a diced tape). The wafer is held by the sheet, and in this state, the wafer is pressed and bonded to the surface of a substrate (such as a wafer). In this bonding technique, the sheet must be peeled off from the wafer after the wafer is pressed onto the surface of the substrate. [Prior Art Documents] [Patent Documents]

[0003] Patent Document 1: Japanese Patent Application Publication No. 2018-160687 [Summary of the Invention]

[0004] (Problem to be Solved by the Invention) On the other hand, in the prior bonding technology disclosed in Patent Document 1, sometimes a situation arises where the sheet cannot be smoothly peeled off from the wafer after pressing the wafer onto the surface of the substrate. In such cases, when attempting to pull the sheet off the wafer, there is a risk of adverse effects on the wafer due to the adhesive force remaining between them (such as the effect of tearing the bonded wafer off the surface of the substrate, or the effect of wafer breakage). Moreover, such adverse effects on the wafer may lead to a decrease in production efficiency and a deterioration in yield.

[0005] Therefore, the object of the present invention is to facilitate the peeling of the bonded sheet from the workpiece in a bonding technique that uses a workpiece attached to the surface of a sheet as the object, thereby suppressing adverse effects on the workpiece and increasing the peeling speed. (Technical means to solve the problem)

[0006] The joining device of the present invention has the following configuration. The joining device includes a sheet holding portion, a pressing portion, and a peripheral holding portion. The sheet holding portion is a portion that holds the peripheral portion of a sheet to which a first workpiece is attached. The pressing portion has an adsorption surface formed on its front end face, which holds the first workpiece by adsorbing the back side of the sheet, and by bringing the adsorption surface close to the surface of a second workpiece, the first workpiece can be pressed onto the surface of the second workpiece. The peripheral holding portion is a portion that holds the peripheral area of ​​the area of ​​the sheet to which the first workpiece is attached when the first workpiece is pressed.

[0007] Furthermore, the joining device further comprises the following configuration (Example 1). A retractable surface is further formed around the adsorption surface on the front end face of the pressing portion, retracting from the adsorption surface. The peripheral holding portion is itself annular and has an annular adsorption surface that adsorbs and holds the entire peripheral area. The pressing portion and the peripheral holding portion have a sealing structure that seals the outer periphery of the retractable surface with the inner periphery of the peripheral holding portion, thereby forming a sealed space between the adsorption surfaces when the sheet is adsorbed onto the adsorption surface of the pressing portion and the adsorption surface of the peripheral holding portion in the joining device. Moreover, when the first workpiece is pressed, the joining device reduces the internal pressure of the sealed space, causing the portion between the adsorption surface of the pressing portion and the adsorption surface of the peripheral holding portion in the sheet to deform towards the retractable surface of the pressing portion.

[0008] According to the above-described sample 1, when the internal pressure of the sealed space is reduced, the sheet can be bent or buckled at the periphery outside the adsorption surface by utilizing the step difference between the adsorption surface and the retraction surface of the pressing part. As a result, the peeling angle of the sheet to the first workpiece can be increased. Moreover, by increasing the peeling angle in this way, the sheet can be easily peeled off from the first workpiece after pressing it.

[0009] As described in the above-described coupling device, the sealing structure can be formed by slidingly fitting the pressing part without gaps inside the peripheral retaining part (parameter 2).

[0010] Based on the above-mentioned state 2, a sealed structure can be constructed without increasing the number of components of the device.

[0011] In the bonding device of the above-described form 1 or 2, at least one of the adsorption surface of the pressing part and the adsorption surface of the peripheral holding part is configured to adsorb the back side of the sheet by vacuum attraction. In such a bonding device, the internal pressure of the sealed space can be reduced by vacuum attraction (form 3).

[0012] According to the above-described sample 3, since the vacuum attraction used to adsorb the sheet on the adsorption surface can be used to reduce the internal pressure of the sealed space, there is no need to set up a separate mechanism (pressure reduction section) for reducing the internal pressure of the sealed space. As a result, the structure of the joining device can be kept simple.

[0013] The engagement device according to any one of the above embodiments 1 to 3 may have the following configuration (assembly 4). The pressing part may have a sliding pin, which may be configured to slide in a direction perpendicular to the adsorption surface of the pressing part, and by sliding, it may protrude from a predetermined position within the adsorption surface. In such an engagement device, before the first workpiece is pressed, in a state where the internal pressure of the sealed space is reduced, the front end of the sliding pin may protrude from the adsorption surface of the pressing part to a predetermined height, and then, when the first workpiece is pressed, the front end of the sliding pin may retract to the same height as the adsorption surface of the pressing part.

[0014] According to the above-described state 4, by making the front end of the sliding pin protrude from the adsorption surface of the pressing part to a predetermined height before pressing the first workpiece, the sheet can be deformed into a convex shape on the adsorption surface of the pressing part. As a result, a force (peeling force) can be generated to peel the sheet from the first workpiece. At this time, the peeling angle of the sheet to the first workpiece becomes larger as described above. Therefore, by generating the above-described peeling force, the adhesion force between the first workpiece and the sheet can be reduced efficiently. By reducing the adhesion force between the first workpiece and the sheet in advance before pressing the first workpiece, it is easier to peel the sheet from the first workpiece after pressing (joining) the first workpiece.

[0015] In the engagement device of the above-described state 4, after the first workpiece is pressed, when the adsorption surface of the pressing part is moved back from the surface of the second workpiece, only the adsorption surface of the pressing part can be moved back without the sliding pin moving back. In this way, the first workpiece can be pressed only by the sliding pin, and then the sliding pin can also be moved back (state 5).

[0016] According to the above-described configuration 5, by only retracting the adsorption surface of the pressing part without retracting the sliding pin, the sheet is peeled off to the periphery of the sliding pin, and at this time, a peeling angle is easily generated between the sheet and the first workpiece. As a result, it is easier to peel the sheet off the first workpiece after pressing (joining) it. (Effects compared to prior art)

[0017] According to the present invention, in a bonding technique that takes a workpiece attached to the surface of a sheet as the object, it is possible to make it easier to peel the bonded sheet from the workpiece, thereby suppressing adverse effects on the workpiece and increasing the peeling speed.

Implementation Method

[0019] [1] Embodiment [1-1] Bonding Apparatus Figure 1(A) is a conceptual diagram showing a bonding apparatus of an embodiment. The bonding apparatus is a device for pressing and bonding a wafer (LSI or IC, etc., hereinafter referred to as "first workpiece W1") to the surface of a substrate (wafer, etc., hereinafter referred to as "second workpiece W2"), and includes: a holding mechanism 1, a pressing mechanism 2, an alignment stage 3, a detection sensor 4, and a control device 5.

[0020] The holding mechanism 1 includes: a sheet holding part 11, a stage 12, and a drive part 13.

[0021] The sheet holding part 11 is a part that holds the periphery of an elastically deformable sheet Sw (such as a cutting strip) in a state in which tension is applied to the sheet Sw. In this embodiment, the sheet Sw is prepared with a plurality of first workpieces W1 attached to one side of it, and is held in the sheet holding part 11 with the one side facing downward.

[0022] The stage 12 is a portion that holds the second workpiece W2 below the sheet Sw held in the sheet holding portion 11, and it has a clamping function (vacuum suction or electrostatic clamp, etc.) for fixing the second workpiece W2. Here, a circuit is formed on the second workpiece W2, and a predetermined position corresponding to the circuit (specifically, a predetermined position that can be connected to the circuit) is set on the surface of the second workpiece W2 as the engagement position Pt of the first workpiece W1. Therefore, on the stage 12, the second workpiece W2 is held with the engagement surface of the first workpiece W1 (the surface of the first workpiece W1 with the engagement position Pt) facing upwards.

[0023] The drive unit 13 is a mechanism capable of moving the stage 12 up and down and adjusting the position of the stage 12 in the horizontal plane. It is, for example, composed of a ball screw and a motor. According to the position adjustment of the stage 12 by the drive unit 13, when one workpiece (hereinafter referred to as "object workpiece Wt") selected from a plurality of first workpieces W1 attached to the sheet Sw is joined to its corresponding joining position Pt, a position adjustment for aligning the joining position Pt with the object workpiece Wt can be performed before such joining is performed (no high-precision position adjustment is required). Moreover, after such position adjustment, a high-precision position adjustment (positioning) of the object workpiece Wt at the joining position Pt is performed by the pressure station 31 described later.

[0024] In this embodiment, the joining device is configured to press and join a plurality of first workpieces W1 attached to the sheet Sw one by one to the surface of a second workpiece W2 (specifically, the joining position Pt corresponding to each). More specifically, as described below.

[0025] The pressing mechanism 2 includes: a pressing part 21, a peripheral holding part 22, a driving part 23 and 24.

[0026] The pressing part 21 is the portion that presses the workpiece Wt attached to the sheet Sw onto the surface of the second workpiece W2. Specifically, an adsorption surface 21p is formed on the front end face 21a of the pressing part 21 (the lower surface in the example of FIG. 1(A)). The adsorption surface 21p holds the workpiece Wt by adsorbing the back side of the sheet Sw. In this embodiment, the adsorption surface 21p has a configuration (area and shape, etc.) to hold only the workpiece Wt through the sheet Sw. Furthermore, the adsorption surface 21p is configured to adsorb the back side of the sheet Sw by vacuum attraction. Furthermore, the pressing part 21 is configured to move up and down by the power of the driving part 23. A more specific configuration will be described later. The pressing part 21 is configured to move up and down independently of the peripheral holding part 22 described below.

[0027] According to the pressing part 21, after the target workpiece Wt is held on the adsorption surface 21p, the pressing part 21 is lowered to bring the adsorption surface 21p close to the surface of the second workpiece W2, and the target workpiece Wt can be pressed onto the surface of the second workpiece W2 (see Figure 7(A)).

[0028] The peripheral holding portion 22 is a portion that holds the peripheral area of ​​the sheet Sw where the workpiece Wt is attached when the workpiece Wt is pressed. Specifically, the peripheral holding portion 22 is itself ring-shaped and has a ring-shaped adsorption surface 22p that adsorbs and holds the entire peripheral area. In this embodiment, the adsorption surface 22p is configured to adsorb the back side of the sheet Sw using vacuum suction. Furthermore, the peripheral holding portion 22 is configured to move up and down by the power of the drive portion 24.

[0029] According to the peripheral holding portion 22, when the pressing portion 21 presses the workpiece Wt, the peripheral area of ​​the sheet Sw to which the workpiece Wt is attached can be held in advance by the adsorption surface 22p and kept in the same position (see Figure 7(A)). In this way, when the workpiece Wt is pressed, the sheet Sw can be appropriately flexed inside the adsorption surface 22p.

[0030] Furthermore, the pressing mechanism 2 has the following configuration. Figure 1(B) is a conceptual diagram showing the enlarged configuration of the pressing mechanism 2 and its surroundings. As shown in the figure, a retracting surface 21q is formed around the adsorption surface 21p on the front end face 21a of the pressing part 21. Thereby, the front end face 21a is formed into a trapezoid with a raised central portion. Moreover, the pressing part 21 and the peripheral holding part 22 have a sealing structure that seals the outer periphery of the retracting surface 21q with the inner periphery of the peripheral holding part 22. Thereby, when the sheet Sw is adsorbed onto the adsorption surface 21p of the pressing part 21 and the adsorption surface 22p of the peripheral holding part 22, a sealed space Qs can be formed between the adsorption surfaces 21p and 22p (see Figures 3(B) and 4(A)).

[0031] In this embodiment, the aforementioned airtight structure is formed by the pressing part 21 being slidably fitted into the inner side of the peripheral retaining part 22 without gaps (see Figure 1(B)). In this way, an airtight structure can be constructed without increasing the number of components of the connecting device.

[0032] Based on this sealed structure, by reducing the internal pressure of the sealed space Qs when the first workpiece W1 is pressed, the portion between the adsorption surface 21p of the pressing part 21 and the adsorption surface 22p of the peripheral holding part 22 in the sheet Sw can be deformed toward the retractable surface 21q of the pressing part 21 (see Figure 4(A)). In this embodiment, the internal pressure of the sealed space Qs is reduced by the vacuum attraction when the adsorption surfaces 21p and 22p adsorb the sheet Sw.

[0033] In this way, the sheet Sw can be bent or buckled around the periphery outside the adsorption surface 21p by utilizing the step difference between the adsorption surface 21p and the retraction surface 21q of the pressing part 21 (see Figure 4(A)). As a result, the peeling angle θp of the sheet Sw relative to the first workpiece W1 can be increased (see Figure 4(B)). Moreover, by increasing the peeling angle θp in this way, the sheet Sw can be easily peeled off from the first workpiece W1 after pressing.

[0034] Furthermore, since the pressure inside the sealed space Qs can be reduced by using the vacuum attraction of the adsorption sheets Sw on the adsorption surfaces 21p and 22p, there is no need to provide a separate mechanism (pressure reduction unit) for reducing the pressure inside the sealed space Qs. As a result, the configuration of the joining device can be kept simple.

[0035] In addition to the above-described configuration, the pressing part 21 also has a sliding pin 211 (see Figure 1(B)). This sliding pin 211 is configured to slide in a direction perpendicular to the adsorption surface 21p of the pressing part 21, and by this sliding, it can protrude from a predetermined position within the adsorption surface 21p. In this embodiment, the predetermined position is set to be the center position of the adsorption surface 21p. Furthermore, the sliding of the sliding pin 211 is performed by the power of the driving part 212.

[0036] More specifically, in the pressing part 21, a guide hole 210 is provided to make the sliding pin 211 slidable, with the opening facing the adsorption surface 21p of the pressing part 21. Furthermore, the sliding pin 211 can slide along the guide hole 210 and can move back and forth between a position where the front end is retracted into the guide hole 210 (see Figure 4(A)) and a position where the front end protrudes from the guide hole 210 (see Figure 8(A)). In this embodiment, the sliding pin 211 is provided in a state where it is slidably fitted into the guide hole 210 without gaps, so that the guide hole 210 also becomes a vacuum during vacuum suction. Details regarding the function and operation of the sliding pin 211 will be described later.

[0037] The alignment stage 3 (refer to Figure 1(A)) is composed of multiple platforms to enable high-speed and high-precision position adjustment of the pressing mechanism 2. Specifically, the alignment stage 3 includes: a pressing station 31; and a wide-range stage 32, which is capable of position adjustment over a wider range than the pressing station 31. Moreover, the pressing station 31 is provided on the wide-range stage 32, and the pressing mechanism 2 is provided on the pressing station 31. Here, the pressing station 31 uses a piezoelectric element as the platform drive source, enabling high-precision (nanoscale precision) platform position adjustment. On the other hand, the wide-range stage 32 uses a ball screw and a motor as the platform drive source, enabling high-speed movement of the platform over a wide range.

[0038] Based on such an alignment platform 3, the position adjustment of the pressing mechanism 2 can be performed in two stages using the wide-range platform 32 and the pressing station 31. Specifically, the pressing mechanism 2 can be moved over a wide range and at high speed without requiring high precision using the wide-range platform 32, and then the position adjustment of the pressing mechanism 2 can be performed with high precision (nanoscale precision) using the pressing station 31.

[0039] Therefore, when positioning the object workpiece Wt relative to the engagement position Pt set on the surface of the second workpiece W2, the pressing mechanism 2 can be moved at high speed to a position that can hold the object workpiece Wt from the back side (in other words, above the engagement position Pt corresponding to it) by means of the wide range stage 32.

[0040] Furthermore, since the sheet material Sw is elastically deformable, even after the workpiece Wt is held by the adsorption surface 21p via the sheet material Sw, the position adjustment of the pressing mechanism 2 (i.e., the position adjustment of the workpiece Wt) performed by the pressing station 31 can be performed while maintaining this state, allowing the sheet material Sw to be elastically deformed. Therefore, the positioning of the workpiece Wt relative to the engagement position Pt can be performed with high precision by means of the pressing station 31 without being affected by the sheet material Sw. As a result, the positioning accuracy of the engagement position Pt can be significantly improved.

[0041] Thus, the engagement device according to this embodiment can simultaneously accommodate the movement of the high-speed pressing mechanism 2 over a wide range and the high-precision positioning adjustment of the workpiece Wt at the engagement position Pt. As a result, even when the engagement positions Pt are widely dispersed, high-precision positioning of the workpiece Wt at the engagement position Pt can be performed individually and at high speed.

[0042] In this embodiment, the positioning station 3 further includes a posture adjustment mechanism 33 (see Figure 2) capable of adjusting the posture of the positioning station 31 relative to the wide-range station 32. Specifically, the posture adjustment mechanism 33 is configured by supporting the positioning station 31 at three points relative to the wide-range station 32.

[0043] Figure 2 is a conceptual diagram showing the configuration of the posture adjustment mechanism 33 of the three-point support piezoelectric station 31 at each point. At each point, the posture adjustment mechanism 33 is configured such that a piezoelectric actuator 331 capable of adjusting the protrusion of the movable part 331A is erected on the wide-range platform 32, and the front end of the movable part 331A contacts the back of the piezoelectric station 31 to support the piezoelectric station 31. Furthermore, in the example of Figure 2, the following situation is shown: in order to stabilize the support state of the piezoelectric actuator 331 on the piezoelectric station 31, the body part 331B of the piezoelectric actuator 331 is connected to the piezoelectric station 31 via a ring-shaped leaf spring 332.

[0044] According to such a posture adjustment mechanism 33, the posture of the pressure radio 31 can be adjusted in such a way that the pressure radio 31 is parallel to the wide-range station 32.

[0045] Furthermore, when the object workpiece Wt is pressed against the surface of the second workpiece W2, a force equal to the pressure generated at this time (the reaction force applied to the pressure station 31 at this time) is concentrated at three points supporting the pressure station 31 (piezoelectric actuator 331). For this purpose, a pressure sensor 333 (see Figure 2) is incorporated into the posture adjustment mechanism 33 to measure the force (equal to the pressure) applied to the pressure station 31 at three points. In this way, the pressure generated when the object workpiece Wt is pressed against the surface of the second workpiece W2 can be measured by the pressure sensor 333.

[0046] The detection sensor 4 (refer to Figure 1(A)) is a sensor for detecting alignment marks formed on the first workpiece W1 and the second workpiece W2.

[0047] Here, in this embodiment, the portions of the first workpiece W1 and the second workpiece W2 where the engagement position Pt of the first workpiece W1 is provided become a set of engagement objects that engage with each other. Moreover, one set of engagement objects selected from all groups (the object workpiece Wt and the portions of the second workpiece W2 where the engagement position Pt of the object workpiece Wt is provided) are set as aligned objects before engagement. Furthermore, during alignment, the relative positional relationship is adjusted by the position adjustment performed by the drive unit 13 of the holding mechanism 1 (without high-precision position adjustment) so that when viewed from a direction perpendicular to the two-dimensional imaginary plane (the horizontal plane in this embodiment) (the vertical direction in this embodiment), they become overlapping (opposite state). From this state, the positional relationship is further adjusted by the high-precision position adjustment (positioning) performed by the pressure station 31 so that the position of the object workpiece Wt and the engagement position Pt are consistent when viewed from the vertical direction.

[0048] Moreover, in this embodiment, in order to perform the high-precision alignment as described above for any group of mating objects, alignment marks are formed for each group of mating objects.

[0049] The detection sensor 4 is an image sensor that acquires an image containing the image or shadow of the alignment mark (the mark on the side of the target workpiece Wt and the image or shadow of the mark on the corresponding side of the second workpiece W2) by detecting light from the light source 41 (not shown). In this embodiment, IR light (infrared light) is used as the light from the light source 41, and the sheet Sw and the stage 12 are made of materials that allow IR light to pass through. Furthermore, the IR light can be captured by passing the light from the light source 41 through a bandpass filter.

[0050] Furthermore, the detection sensor 4 is installed together with the pressure station 31 on the wide-range stage 32. Therefore, when the detection sensor 4 is intended to acquire an image containing the alignment mark, the light source 41 is configured to illuminate the alignment mark from the back side of the sheet Sw (the upper side in FIG. 1(A)). In this way, the detection sensor 4 detects the reflected light at the alignment mark. On the other hand, when the detection sensor 4 is intended to acquire an image containing the shadow of the alignment mark, the light source 41 is configured to illuminate the alignment mark from the back side of the stage 12 (the lower side in FIG. 1(A)). In this way, the detection sensor 4 detects the transmitted light that casts a shadow on the alignment mark.

[0051] Furthermore, in this embodiment, light incident from the alignment mark side onto the adsorption surface 21p of the pressing part 21 is used by the detection sensor 4 to acquire an image (including the image or shadow of the alignment mark). Specifically, as described below, a light path Rm is formed in the pressing mechanism 2, which is used to transmit and guide light incident from the alignment mark side onto the adsorption surface 21p of the pressing part 21 to the detection sensor 4 (see Figure 1(A)). Moreover, in this embodiment, in order to realize the formation of such a light path Rm, the pressing part 21 is made of a material that allows IR light to pass through (quartz or acrylic, etc.).

[0052] Based on the detection sensor 4 and its associated configuration, positioning (position offset correction) using the alignment mark can be performed while observing the alignment mark using the detection sensor 4 provided on the wide-range stage 32. Therefore, positioning using the alignment mark can be performed while the target workpiece Wt is close to the second workpiece W2 (see FIG5). As a result, after alignment, the target workpiece Wt can be pressed onto the surface of the second workpiece W2 without causing a position offset from that point (see FIG7(A)). Therefore, the positioning accuracy of the engagement position Pt can be significantly improved.

[0053] The control device 5 is composed of a processing device (CPU, etc.) and a memory device (RAM or ROM, etc.), and controls various parts of the bonding device (holding mechanism 1, pressing mechanism 2, alignment stage 3, detection sensor 4, etc.) according to a control program installed on the bonding device. In this embodiment, the control device 5 can perform the bonding process described below.

[0054] Here, the aforementioned control program can be saved in a readable state on a portable memory medium (such as flash memory) before installation onto the bonding device, or it can be saved in a downloadable state on other servers, etc. Furthermore, the bonding process described below is not limited to the case where it is implemented by software through program execution; it can be implemented by hardware through processing circuitry built into the bonding device.

[0055] [1-2] The joint process Figures 3(A) to 8(B) are conceptual diagrams showing the state changes of the joint device caused by the execution of the joint process.

[0056] At the start of the joining process, in order to position the target workpiece Wt relative to the joining position Pt set on the surface of the second workpiece W2, the control device 5 first moves the pressing mechanism 2 at high speed to a position that can hold the target workpiece Wt from the back side (in other words, above the corresponding joining position Pt) by controlling the wide-range stage 32 (step S101. See Figure 3(A)). At this time, while the control device 5 observes the alignment marks set on the target workpiece Wt and the joining position Pt (the mark on the side of the target workpiece Wt and the mark on the side of the corresponding second workpiece W2) by the detection sensor 4, it controls the drive unit 13 to adjust the position of the stage 12, thereby also adjusting the position of the joining position Pt relative to the target workpiece Wt (no high-precision position adjustment is required).

[0057] After step S101, the control device 5 lowers the pressing part 21 and the peripheral holding part 22 by controlling the drive parts 23 and 24 of the pressing mechanism 2. This causes the adsorption surface 21p of the pressing part 21 to adsorb the back side of the area on the sheet Sw where the workpiece Wt is attached using vacuum suction, and the adsorption surface 22p of the peripheral holding part 22 to adsorb the back side of the peripheral area using vacuum suction (step S102, see Figure 3(B)). At this time, the control device 5 pre-aligns the adsorption surface 21p of the pressing part 21 and the adsorption surface 22p of the peripheral holding part 22 on the same plane. Furthermore, the control device 5 pre-retracts the front end of the sliding pin 211 into the guide hole 210 by controlling the drive part 212 (see Figure 4(A)).

[0058] Thereby, the workpiece Wt is held by the adsorption surface 21p of the pressing part 21 via the sheet Sw, and the peripheral area of ​​the area on which the workpiece Wt is attached in the sheet Sw is held by the adsorption surface 22p of the peripheral holding part 22.

[0059] Furthermore, by adsorbing the sheet Sw on the adsorption surface 21p of the pressing part 21 and the adsorption surface 22p of the peripheral holding part 22 in step S102, a sealed space Qs is formed between the adsorption surfaces 21p and 22p. Moreover, the internal pressure of the sealed space Qs is reduced by the vacuum attraction in the adsorption surfaces 21p and 22p.

[0060] Accordingly, the portion between the adsorption surface 21p of the pressing portion 21 and the adsorption surface 22p of the peripheral holding portion 22 in the sheet Sw deforms toward the retracting surface 21q of the pressing portion 21. Moreover, by deforming the sheet Sw in this way, the sheet Sw can bend or buckle at the outer periphery of the adsorption surface 21p of the pressing portion 21 (see Figure 4(A)), and as a result, the peeling angle θp of the sheet Sw to the first workpiece W1 can be increased (see Figure 4(B)). In this embodiment, by lowering the pressing portion 21 while keeping the peripheral holding portion 22 in the same position, the peeling angle θp gradually increases.

[0061] By increasing the peeling angle θp in this way, the sheet Sw can be easily peeled off from the first workpiece W1 after the first workpiece W1 is pressed. In other words, the sheet Sw after the first workpiece W1 is pressed (joined) becomes easy to peel off from the first workpiece W1.

[0062] After step S102, the control device 5 adjusts the position of the pressing mechanism 2 with high precision (nano-level precision) by controlling the press station 31 (step S103. See Figure 5).

[0063] Specifically, the control device 5 observes an image (the image or shadow of the mark on the side of the object workpiece Wt and the corresponding mark on the side of the second workpiece W2) provided on the object workpiece Wt and the engagement position Pt using the detection sensor 4, and adjusts the position of the object workpiece Wt with high precision so that the two corresponding marks are correctly overlapped. In this way, the positioning of the object workpiece Wt relative to the engagement position Pt is performed with high precision.

[0064] After step S103, before pressing the first workpiece W1, the control device 5 maintains the state of reducing the internal pressure of the sealed space Qs, so that the front end of the sliding pin 211 protrudes from the adsorption surface 21p of the pressing part 21 to a predetermined height (step S104. See Figure 6).

[0065] In this way, the sheet Sw can be deformed in a convex shape on the adsorption surface 21p of the pressing part 21, and as a result, a force (peeling force) can be generated to peel the sheet Sw from the first workpiece W1. Here, the predetermined height is set such that even if the sheet Sw is deformed in a convex shape on the adsorption surface 21p, it will not have an adverse effect on the first workpiece W1 (such as the effect of the first workpiece W1 being damaged due to bending).

[0066] Furthermore, at this time, the peel angle θp of the sheet Sw to the first workpiece W1 has increased as described above. Therefore, by generating the peel force described above, the adhesion force between the first workpiece W1 and the sheet Sw can be reduced efficiently. By reducing the adhesion force between the first workpiece W1 and the sheet Sw in advance before pressing the first workpiece W1, it is easier to peel the sheet Sw from the first workpiece W1 after pressing (joining) the first workpiece W1.

[0067] After step S104, the control device 5 lowers the pressing part 21 by controlling the drive part 23 of the pressing mechanism 2, thereby pressing the object workpiece Wt onto the surface of the second workpiece W2 (step S105. See Figure 7(A)). At this time, the control device 5 retracts the front end of the sliding pin 211 to the same height as the adsorption surface 21p of the pressing part 21 by controlling the drive part 212. Furthermore, the control device 5 lowers the pressing part 21 until the output of the pressure sensor 333 reaches the target value (in other words, until the pressing force reaches the target value).

[0068] Furthermore, in step S105, when the pressing part 21 is lowered, the control device 5 keeps the peripheral holding part 22 in the same position. In this way, the sheet Sw can be appropriately flexed when the target workpiece Wt is pressed, and as a result, the peeling angle θp of the sheet Sw relative to the first workpiece W1 can be gradually increased (see Figure 7(B)).

[0069] After step S105, the control device 5 raises the pressing part 21 by controlling the drive part 23 of the pressing mechanism 2, thereby causing the adsorption surface 21p of the pressing part 21 to retract from the surface of the second workpiece W2 (step S106. See Figure 8(A)). At this time, the control device 5 further controls the drive part 212 to retract only the adsorption surface 21p of the pressing part 21 without retracting the sliding pin 211, thereby pressing the first workpiece W1 only by means of the sliding pin 211. Afterwards, the control device 5 also retracts the sliding pin 211 by controlling the drive part 212 (step S107. See Figure 8(B)).

[0070] By causing the adsorption surface 21p of the pressing part 21 to retract without causing the sliding pin 211 to retract, the sheet Sw is peeled off to the periphery of the sliding pin 211. At this time, a peeling angle θp is easily generated between the sheet Sw and the first workpiece W1. As a result, it is easier to peel the sheet Sw from the first workpiece W1 after the first workpiece W1 is pressed (joined).

[0071] Thus, according to this embodiment, in the bonding technique that takes the first workpiece W1 attached to the surface of the sheet Sw as the object, it is easier to peel the bonded sheet Sw from the first workpiece W1, thereby suppressing adverse effects on the first workpiece W1 and increasing the peeling speed. Moreover, the control device 5 can perform such bonding processing (steps S101 to S107) one by one on a plurality of first workpieces W1 attached to the sheet Sw.

[0072] [2] Variation Example [2-1] First Variation Example In the above-mentioned coupling device, the sealing structure that seals the outer periphery of the rearward surface 21q and the inner periphery of the peripheral retaining part 22 can be formed by separating them by a bellows or an elastic body (leaf spring, etc.).

[0073] [2-2] Second variation In the above-described joining device, the pressing mechanism 2 is not limited to being configured such that both the adsorption surface 21p of the pressing part 21 and the adsorption surface 22p of the peripheral holding part 22 can be used to adsorb the back side of the sheet Sw by vacuum attraction, but can be appropriately modified to be configured such that only one adsorption surface can be used to adsorb the back side of the sheet Sw by vacuum attraction.

[0074] [2-3] Third variation: In the above-described coupling device, the pressing mechanism 2 may be appropriately modified to utilize a different configuration than that in which the adsorption surfaces 21p and 22p are used to adsorb the sheet Sw by vacuum attraction, thereby reducing the pressure inside the sealed space Qs. Specifically, the pressing mechanism 2 may be appropriately modified to have a configuration that includes a dedicated pressure-reducing section for reducing the pressure inside the sealed space Qs.

[0075] [2-4] Fourth variation: In the control process described above, the control device 5 can perform the following process. The control device 5 measures the pressure generated during pressing in step S105 at three points supporting the pressure station 31 using pressure sensors 333. Furthermore, by feeding back the three measured values ​​obtained at this time to the posture adjustment mechanism 33, the control device 5 can adjust the posture of the pressure station 31 so that all three measured values ​​are within a predetermined range during the next pressing. Here, the predetermined range is a range set in such a way that when all three measured values ​​are within this range, it is permissible to presume that the pressure station 31 is parallel to the wide-range station 32.

[0076] Specifically, the control device 5 can use three measured values ​​to calculate the offset of the measured values ​​from the reference values ​​(center values, etc.) within the predetermined range and the difference between the measured values. Based on the calculated values, the protrusion of the movable part 331A of each piezoelectric actuator 331 is adjusted so that all three measured values ​​become values ​​within the predetermined range when pressed next time.

[0077] According to this control process, whenever the object workpiece Wt is pressed onto the surface of the second workpiece W2, the posture of the pressing station 31 can be adjusted so that the pressing station 31 is parallel to the wide-range station 32. In this way, the pressing station 31 can always be kept parallel to the wide-range station 32.

[0078] [2-5] Fifth variation: The above-mentioned joining device may be appropriately modified to join the first workpiece W1 and the second workpiece W2 in a posture in which the joining surfaces are oriented in the lateral direction (horizontal direction).

[0079] [2-6] Sixth variation The bonding device described above is not limited to bonding a wafer (first workpiece W1) to a substrate (second workpiece W2), but can also be applied to bonding a wafer (first workpiece W1) to another wafer (second workpiece W2).

[0080] It should be understood that the above description of embodiments and variations is illustrative in all respects and not limiting. The scope of this invention is defined by the claims, not by the embodiments and variations described above. Furthermore, it is intended that the scope of this invention include all modifications within the scope of the claims and having the same meaning as the claims.

[0081] Furthermore, from the above-described embodiments and variations, a portion of the composition of the coupling device can be extracted as the object of the invention, or a portion or all of the coupling process (including the corresponding control method and coupling method) can be extracted, and then the program used to execute them can be extracted. [Simplified Explanation of the Diagram]

[0018] Figure 1(A) is a conceptual diagram showing the coupling device in an embodiment, and Figure 1(B) is a concept diagram showing an enlarged view of the pressing mechanism and its surrounding components of the coupling device. Figure 2 is a conceptual diagram showing the configuration of each point of the posture adjustment mechanism of the three-point support press radio. Figure 3(A) is a conceptual diagram showing the state changes of the coupling device resulting from the execution of the coupling process, and Figure 3(B) is a conceptual diagram showing subsequent state changes. Figure 4(A) is a concept diagram showing an enlarged view of the pressing mechanism and its surrounding components of the coupling device in the state shown in Figure 3(B), and Figure 4(B) is an enlarged view of the J1 area in Figure 4(A). Figure 5 is a conceptual diagram showing the state changes of the coupling device resulting from the execution of the coupling process. Figure 6 is a conceptual diagram showing the state changes of the coupling device resulting from the execution of the coupling process. Figure 7(A) is a conceptual diagram showing the state changes of the coupling device resulting from the execution of the coupling process, and Figure 7(B) is an enlarged view of the J2 area in Figure 7(A). Figure 8(A) is a conceptual diagram showing the state changes of the engagement device resulting from the execution of the engagement process, and Figure 8(B) is a conceptual diagram showing the subsequent state changes.

Claims

1. A joining device comprising: a sheet holding portion holding a peripheral portion of a sheet to which a first workpiece is attached; a pressing portion having an adsorption surface formed on its front end face, the adsorption surface holding the first workpiece through the sheet by adsorbing the back side of the sheet, and pressing the first workpiece onto the surface of the second workpiece by bringing the adsorption surface close to the surface of the second workpiece; and a peripheral holding portion holding a peripheral region of the area of ​​the sheet to which the first workpiece is attached when the first workpiece is pressed; wherein, on the front end face of the pressing portion, a retracting surface retracting from the adsorption surface is further formed around the adsorption surface, and the peripheral holding portion itself is annular and has an annular adsorption surface that adsorbs and holds the peripheral region as a whole. The aforementioned pressing portion and the aforementioned peripheral holding portion have a sealing structure that seals the outer periphery of the aforementioned retracting surface and the inner periphery of the aforementioned peripheral holding portion. This creates a sealed space between the adsorption surfaces when the sheet is adsorbed onto the adsorption surface of the pressing portion and the adsorption surface of the aforementioned peripheral holding portion. The pressing portion has a sliding pin configured to slide in a direction perpendicular to the adsorption surface of the pressing portion and to protrude from a predetermined position within the adsorption surface. When the first workpiece is pressed onto the surface of the second workpiece, before the first workpiece contacts the second workpiece, the internal pressure within the sealed space is reduced, causing the portion between the adsorption surface of the pressing portion and the adsorption surface of the aforementioned peripheral holding portion in the sheet to deform towards the retracting surface side of the pressing portion. This state is maintained, and the leading end of the sliding pin protrudes from the adsorption surface of the pressing portion to a predetermined height. Subsequently, when the first workpiece comes into contact with the surface of the second workpiece, the front end of the sliding pin is retracted to the same height as the adsorption surface of the pressing part.

2. The coupling device as claimed in claim 1, wherein, The aforementioned sealed structure is formed by the pressing part being slidably fitted into the inner side of the aforementioned peripheral retaining part without gaps.

3. The coupling device as claimed in claim 1 or 2, wherein, At least one of the adsorption surface of the pressing part and the adsorption surface of the peripheral holding part is configured to be able to adsorb the back side of the sheet by vacuum attraction, thereby reducing the internal pressure of the sealed space by vacuum attraction.

4. The coupling device as claimed in claim 1, wherein, After the first workpiece is pressed, when the adsorption surface of the pressing part moves backward from the surface of the second workpiece, only the adsorption surface of the pressing part moves backward without the sliding pin moving backward. In this way, the first workpiece is pressed only by the sliding pin, and then the sliding pin moves backward as well.

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