Joint repair methods

Abstract

To provide a technique of allowing formation of an excellent joining state between joining targets even if a part which is not joined can be generated in a joining process of joining targets such as semiconductor wafers to each other.SOLUTION: A method for repairing a join repairs a joining state of a part which is not joined by applying a laser beam to that part when a part which is not joined is generated in at least a part of a joining target site in a joining process of joining two joining targets in the joining target site set in faces opposed to each other of the two joining targets.SELECTED DRAWING: Figure 4

Description

Technical Field

[0001] The present invention relates to a bonding technique using laser light.

Background Art

[0002] As a semiconductor device manufacturing technique, there is a process for bonding two semiconductor wafers (hereinafter referred to as "bonding process"). For example, in Patent Document 1, with two semiconductor wafers overlapped, pressure is applied from the back side of one with gas or liquid and received on the back side of the other to sandwich the two semiconductor wafers, and in that state, laser light is irradiated onto their opposing surfaces to bond the semiconductor wafers together. Such a technique is described.

[0003] In recent years, such a bonding process is used in the semiconductor device manufacturing technique when sealing sensors (such as acceleration sensors and gyro sensors) or micro machines (such as actuators) in the device, or when manufacturing a semiconductor device with a three-dimensional structure in which chips are stacked.

Prior Art Documents

Patent Documents

[0004]

Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] On the other hand, in the bonding process described above, as described in Patent Document 1, when semiconductor wafers are stacked and pressed together, a holding part may be required to hold the semiconductor wafers. In that case, even if bonding is required in the part of the semiconductor wafer held by the holding part, the laser light cannot be irradiated to that part, and that part becomes an unbonded part. When such unbonded parts occur, problems such as waste of that part may occur, and problems such as adverse effects on processing and equipment in subsequent processes (such as the cutting process) (adverse effects such as fluttering or peeling of the semiconductor wafer) may occur.

[0006] Furthermore, even if a laser beam can be irradiated onto the portion held by the holding part by some means, it may not be possible to apply appropriate pressure to that portion in the preceding process (the process of clamping the semiconductor wafer), resulting in a problem where that portion becomes poorly bonded and unbonded. This problem can also occur when bonding the entire semiconductor wafer by heating it while it is clamped. Specifically, if such a holding part is necessary, the portion held by the holding part may have insufficient clamping pressure even if bonding is required in that portion, leading to a similar problem.

[0007] Therefore, the object of the present invention is to provide a technology that makes it possible to form a good bond between bonding targets, such as semiconductor wafers, even when unbonded areas may occur in a bonding process. [Means for solving the problem]

[0008] The bonding repair method according to the present invention is a bonding process in which two objects to be bonded are bonded at a bonding target portion set within their opposing surfaces, and if an unbonded portion occurs in at least a part of the bonding target portion, the bonding state at the unbonded portion is repaired by irradiating the unbonded portion with laser light.

[0009] According to the above joint repair method, by using laser light, the heating area can be limited to the unjointed area, and as a result, the joint state of the unjointed area can be repaired while preventing adverse effects from heat or light on parts other than the unjointed area. [Effects of the Invention]

[0010] According to the present invention, even if unjoined portions may occur during the joining process, it becomes possible to form a good bond between the objects to be joined. [Brief explanation of the drawing]

[0011] [Figure 1] (A) A cross-sectional view conceptually showing an example of two objects to be joined in the joining process, and (B) A plan view showing the objects with one of the two objects excluded. [Figure 2] This is a conceptual diagram showing an example of a joining apparatus used in the joining process, with (A) the second stage raised and (B) the second stage lowered. [Figure 3] This is a conceptual diagram showing a state where an unjoined area exists in the target joint. [Figure 4] (A) A conceptual diagram showing an example of a joint repair device used in the joint repair method according to the embodiment, and (B) A plan view showing an example of a first support part used in the embodiment. [Figure 5] (A) is a plan view conceptually showing the arrangement of the object to be joined to the support mechanism of the joining and repair device, and (B) is a plan view conceptually showing the arrangement of the object to be joined when it is rotated in the circumferential direction. [Figure 6] This is a conceptual diagram showing (A) the bypass section and (B) the linear section, which have been reconfigured as joining target sections to avoid interfering materials. [Modes for carrying out the invention]

[0012] [1] Joining process [1-1] Target to be joined Figures 1(A) and 1(B) are conceptual cross-sectional and plan views, respectively, illustrating an example of two bonding targets 101 and 102 to be bonded in a bonding process. Bonding targets 101 and 102 are substrates composed of semiconductor wafers or other substrates. Figure 1(A) is a cross-sectional view taken along the IA-IA line shown in Figure 1(B). Figure 1(B) is a plan view showing one of the two bonding targets 101 and 102, excluding one of them, bonding target 102.

[0013] In the examples shown in Figures 1(A) and 1(B), the object to be joined 101 includes multiple device regions Rd that are separated into individual pieces by cutting along the cutting line Ct. Each device region Rd becomes the base of the device when separated into individual pieces. Each device region Rd is also provided with a recess 103 for forming a cavity within the device. Here, the cavity is a sealed space for encapsulating the elements 104 that perform the function of the device. The elements 104 include sensors (such as acceleration sensors and gyroscopes), micro-machines (such as actuators), and electronic circuits.

[0014] The bonding target 102 is bonded to the bonding target 101 after the elements 104 are placed in the recesses 103 of each device region Rd, and all the recesses 103 are closed. As a result, cavities are formed in each device region Rd, and the elements 104 are sealed within these cavities. Furthermore, the bonding target 102 is separated into individual pieces along with the bonding target 101 by cutting along the cutting line Ct, thereby becoming the lid portion of the device.

[0015] And the bonding of the bonding targets 101 and 102 at this time is performed at the bonding target portion Pt set in their opposing surfaces 101a and 102a as shown in Fig. 1(A). In the example of Fig. 1(B), in order to bond around the depression 103 over the entire circumference in each device region Rd, as the bonding target portion Pt, a rectangular linear portion Pt1 for bonding along the cutting line Ct around the depression 103 is set. The bonding at this linear portion Pt1 is necessary to maintain the cavity as a sealed space in each device obtained by the fragmentation even after fragmentation by cutting at the cutting line Ct.

[0016] Furthermore, in the example of Fig. 1(B), as the bonding target portion Pt, an annular linear portion Pt2 for bonding the bonding targets 101 and 102 over the entire circumference is also set at the peripheral edge Re of the bonding targets 101 and 102. The bonding at this linear portion Pt2 is necessary to suppress the flutter at the peripheral edge Re of the bonding targets 101 and 102 that may occur in the cutting process (cutting at the cutting line Ct).

[0017] And in the bonding process, in order to bond the two bonding targets 101 and 102 at the bonding target portion Pt having the above-described pattern shape, irradiation of laser light to the bonding target portion Pt is executed. Specifically, the bonding process is executed using a bonding device as described below.

[0018] Note that the shapes of the bonding targets 101 and 102 and the pattern shape of the bonding target portion Pt are not limited to those described above, and can be appropriately changed according to the shape and size of the device to be manufactured, the position, line, region, etc. to be bonded. Also, the bonding of the bonding targets 101 and 102 is not limited to being executed by irradiation of laser light to the bonding target portion Pt, and may be appropriately changed to be executed by heating the entire bonding targets 101 and 102 with the pressurized region for the bonding targets 101 and 102 as the bonding target portion Pt.

[0019] [1-2] Bonding Device Fig. 2(A) is a conceptual diagram showing an example of a bonding apparatus used in the bonding process. In the example of Fig. 2(A), the bonding apparatus includes a chamber mechanism 1, a sealing mechanism 2, a pressurizing mechanism 3, a laser light source 4, and a control unit 5. Hereinafter, the configuration of each part will be specifically described.

[0020] <Chamber mechanism 1> The chamber mechanism 1 has a first chamber component 11, a second chamber component 12, and a drive unit 13 that drives at least one of these.

[0021] The first chamber component 11 and the second chamber component 12 are parts that form a sealed space (hereinafter referred to as "chamber 10") for performing the bonding process, and are configured to selectively realize the formation and opening of the chamber 10 by relatively approaching and separating in the vertical direction. More specifically, it is as follows.

[0022] The first chamber component 11 is composed of a first cylindrical part 111 and a first stage 112 that is supported without a gap inside the first cylindrical part 111. The first cylindrical part 111 is arranged with its central axis direction aligned with the vertical direction, and the first stage 112 is horizontally supported by the first cylindrical part 111. Here, the first stage 112 is a stage having transparency to laser light and is formed of, for example, quartz.

[0023] The second chamber component 12 is composed of a second cylindrical part 121 arranged coaxially with the first cylindrical part 111 above the first cylindrical part 111, a second stage 122 that is supported without a gap inside the second cylindrical part 121 and is movable up and down, and a drive unit 123 that moves the second stage 122 up and down. When the upper end of the first cylindrical part 111 and the lower end of the second cylindrical part 121 contact without a gap, a chamber 10 is formed between the first stage 112 and the second stage 122 as shown in Figs. 2(A) and 2(B). In Fig. 2(A), a state where the second stage 122 is raised is shown, and in Fig. 2(B), a state where the second stage 122 is lowered is shown.

[0024] Then, as shown in Figure 2(B), by lowering the second stage 122 and bringing it into surface contact with the back surface 102b of the object to be joined 102, when pressure is applied to the back surface 101b of the object to be joined 101 from the first stage 112 side (the lower side in the example of Figure 2(B)) by the pressurizing mechanism 3 described later, that pressure can be received by the back surface 102b side of the object to be joined 102 (the upper side in the example of Figure 2(B)). In this way, in this joining device, the second stage 122 can function as a support part that receives pressure on the back surface 102b side of the object to be joined 102.

[0025] The drive unit 13 is the part that moves at least one of the first chamber component 11 and the second chamber component 12 in the vertical direction, thereby bringing them relatively closer together and further apart.

[0026] <Seal mechanism 2> The sealing mechanism 2 is a mechanism that divides the space within the chamber 10 into multiple regions (hereinafter referred to as "chamber regions") and seals the spaces between adjacent chamber regions (see Figure 2(B)). Specifically, the sealing mechanism 2 divides the space within the chamber 10 into a first chamber region R1 facing the back surface 101b of the object to be joined 101, and a second chamber region R2 adjacent to the first chamber region R1, and seals the spaces between these chamber regions. More specifically, it is as follows.

[0027] The sealing mechanism 2 consists of a flange portion 21 and a holding portion 22. Here, the flange portion 21 is an annular portion that protrudes toward the central axis of the first cylindrical portion 111 from a position on the inner surface of the first cylindrical portion 111 that is above the first stage 112 (i.e., a position close to the second cylindrical portion 121), and extends to a position where it can face the peripheral edges Re of the objects to be joined 101 and 102 when the objects to be joined 101 and 102 are placed in the chamber 10. The holding portion 22 is made of an annular sealing member (such as an O-ring) and is installed on the upper surface of the tip of the flange portion 21 so as to be able to support the peripheral edges Re of the objects to be joined 101 and 102 around their entire circumference when the objects to be joined 101 and 102 are placed in the chamber 10.

[0028] With this sealing mechanism 2, when the second stage 122 descends and contacts the back surface 102b of the object to be joined 102, the peripheral edges Re of the objects to be joined 101 and 102 are sandwiched between the second stage 122 and the holding portion 22 around their entire circumference. As a result, as shown in Figure 2(B), the space within the chamber 10 is divided into a first chamber region R1 and a second chamber region R2, and the space between these chamber regions is sealed.

[0029] <Pressurization mechanism 3> The pressurizing mechanism 3 is a mechanism that applies pressure to the back surface 101b of the object to be joined 101 by increasing the internal pressure of the first chamber region R1. Specifically, the pressurizing mechanism 3 is a mechanism that uses a gas or liquid as the pressure transmission medium 30, and applies pressure to the back surface 101b of the object to be joined 101 while the pressure transmission medium 30 is in contact with the back surface 101b of the object to be joined 101. More specifically, it is as follows.

[0030] The pressurizing mechanism 3 is capable of adjusting the internal pressure in each chamber region formed by partitioning the chamber 10 with the sealing mechanism 2, thereby reducing the pressure within each chamber region. Furthermore, it is possible to pressurize the first chamber region R1 using the pressure transmission medium 30. Pressurizing the first chamber region R1 is achieved, for example, by supplying the pressure transmission medium 30 (gas or liquid) to the first chamber region R1 using a compression pump. The pressurizing mechanism 3 then applies pressure to the back surface 101b of the object to be joined 101 by making the internal pressure of the first chamber region R1 higher than the internal pressure of the second chamber region R2, utilizing the difference between them.

[0031] <Laser light source 4> The laser light source 4 is the part that emits laser light and is positioned below the first stage 112, which is transparent to laser light. The laser light source 4 can irradiate the objects to be joined 101 and 102 via the first stage 112 with laser light and scan the laser light in a horizontal plane along the pattern shape of the joining target Pt. Furthermore, the laser light source 4 can focus the laser light on the joining point (position of the joining target Pt) between the objects to be joined 101 and 102.

[0032] <Control Unit 5> The control unit 5 consists of processing units such as a CPU and a microcomputer, and controls various operating parts of the bonding device (chamber mechanism 1, pressurizing mechanism 3, laser light source 4, etc.). Specifically, the bonding process is carried out by the control unit 5 performing control according to the following flow.

[0033] The control unit 5 first forms the chamber 10 by bringing the first chamber component 11 and the second chamber component 12 close together and joining them (see Figure 2(A)). Here, the components to be joined 101 and 102 are placed on the holding portion 22 before the chamber 10 is formed.

[0034] Next, the control unit 5 controls the pressurizing mechanism 3 to reduce the internal pressure of the entire chamber 10 until a vacuum is created inside the chamber 10. At this time, the peripheral Re of the joining targets 101 and 102 are not yet sandwiched between the second stage 122 and the holding part 22, and are therefore released from the seal. As a result, the gas present between the joining targets 101 and 102 can be discharged to the outside (into the chamber 10) through the space between the joining targets 101 and 102. Consequently, the internal pressure between the joining targets 101 and 102 can also be reduced.

[0035] Subsequently, the control unit 5 lowers the second stage 122 and brings it into contact with the back surface 102b of the object to be joined 102, thereby sandwiching the peripheral edges Re of the objects to be joined 101 and 102 around their entire circumference between the second stage 122 and the holding part 22 (see Figure 2(B)). This forms the first chamber region R1 and the second chamber region R2, and seals the space between them.

[0036] In this state, the control unit 5 controls the pressurizing mechanism 3 to increase the internal pressure of the first chamber region R1 while keeping the second chamber region R2 in a vacuum state. As a result, the internal pressure of the first chamber region R1 becomes higher than the internal pressure of the second chamber region R2, and a pressure corresponding to the difference between them is applied to the back surface 101b of the objects to be joined 101. As a result, the objects to be joined 101 and 102 are compressed between the pressure transmission medium 30 and the second stage 122 (pressurizing step). At this time, by changing the internal pressure of the first chamber region R1, the pressure applied to the back surface 101b of the objects to be joined 101 can be changed to a desired value. Note that the internal pressure of the first chamber region R1 may be set to a value lower than atmospheric pressure, to a value about the same as atmospheric pressure, or to a value higher than atmospheric pressure, as long as it is higher than the internal pressure of the second chamber region R2.

[0037] After the pressure mechanism 3 applies pressure to the back surface 101b of the object to be joined 101, the control unit 5 maintains this state and controls the laser light source 4 to irradiate the joining target portion Pt of the objects to be joined 101 and 102 with laser light. At this time, the control unit 5 scans the laser light in the horizontal plane along the pattern shape of the joining target portion Pt. In this way, the joining process to join the two objects to be joined 101 and 102 is performed by the joining device.

[0038] Furthermore, the bonding apparatus described above is not limited to one that bonds objects 101 and 102 by irradiating a bonding target Pt having a pattern shape with laser light, but may be appropriately modified to one that bonds objects 101 and 102 by heating the entire object 101 and 102, with the bonding target Pt being a pressurized area over the object 101 and 102.

[0039] [1-3] Occurrence of unjointed areas In the bonding apparatus described above, during the bonding process, the peripheral Re of the bonding targets 101 and 102 are sandwiched between the second stage 122 and the holding part 22 over their entire circumference (see Figures 1(B) and 2(B)). Therefore, as shown in Figure 3, when irradiating the bonding target Pt with laser light, the presence of the sealing mechanism 2 including the holding part 22 prevents the laser light from being irradiated to the portion of the bonding target Pt that is set as the peripheral Re (annular linear portion Pt2), and as a result, that portion becomes an unbonded portion Pu. If such an unbonded portion Pu occurs, it becomes impossible to suppress flapping at the peripheral Re of the bonding targets 101 and 102 that may occur during the cutting process (cutting along the cutting line Ct).

[0040] Furthermore, not only when performing the joining process using the joining device described above, but also when two joining targets 101 and 102 are overlapped and pressed together, if a holding part is required to hold the joining targets 101 and 102, a part of the joining target Pt may be hidden by the holding part (and the mechanism including it). In that case, the part of the joining target Pt that is hidden by the holding part cannot be irradiated with laser light, and that part becomes an unjointed area Pu. When such an unjointed area Pu occurs, problems such as the fluttering problem described above may occur, as well as problems such as the waste of the unjointed area Pu and adverse effects on processing and equipment (such as peeling) in subsequent processes may occur.

[0041] Furthermore, even if it were possible to irradiate the portion of the joining target Pt that is hidden by the holding portion (and the mechanism including it) with laser light by some means, in the preceding process (the process of clamping the joining targets 101 and 102), it would not be possible to apply appropriate pressure to the portion held by the holding portion, which could result in a poorly joined portion of Pu. This problem could also occur when joining the joining targets 101 and 102 by heating the entire structure while clamping it, because if such a holding portion is necessary, the portion held by the holding portion would lack the pressure required for clamping.

[0042] Therefore, even when unjointed areas of Pu may occur during the joining process, the inventors propose a joining repair method that restores the joining state of the unjointed areas of Pu by irradiating them with laser light, in order to enable the formation of a good joining state between the joining targets 101 and 102. The joining repair method will be described in detail below.

[0043] In addition to the reasons mentioned above, other possible causes for the occurrence of unjoined Pu portions include foreign matter being trapped between the two joining targets 101 and 102, preventing them from adhering properly, or insufficient laser power due to a temporary lack of output from the laser light source 4. A method for repairing the joining state of unjoined Pu portions caused by these reasons will be explained in the second modification section below.

[0044] [2] Joint repair method The joint repair method according to this embodiment can be performed using the following joint repair apparatus.

[0045] Figure 4(A) is a conceptual diagram showing an example of a joint repair device. The joint repair device comprises a support mechanism 6, a laser light source 7, and a control unit 8.

[0046] The support mechanism 6 is a mechanism that includes a first support portion 61 and a second support portion 62, and supports the objects to be joined 101 and 102 after the joining step described above by sandwiching them between the first support portion 61 and the second support portion 62 from their back surfaces 101b and 102b. The support mechanism 6 may also have a pressurizing function that further clamps the objects to be joined 101 and 102 while supporting them with the first support portion 61 and the second support portion 62.

[0047] In this embodiment, the first support portion 61 is positioned on the laser beam incidence side (the back surface 101b side of the joint target 101 in the example of Figure 4(A)) relative to the joint targets 101 and 102. The first support portion 61 is a support portion with a window 61w that allows laser light from the laser light source 7 to pass through. Specifically, the first support portion 61 has the window 61w formed such that when the joint targets 101 and 102 are sandwiched between the first support portion 61 and the second support portion 62, at least a portion of the unjoined portion Pu can be seen through the window 61w.

[0048] Figure 4(B) is a plan view showing an example of the first support portion 61 used in the embodiment. In Figure 4(B), the first support portion 61 is shown as one that can be used to repair the joined state of the unjointed portion Pu when the annular linear portion Pt2 of the joining target portion Pt shown in Figure 1(B) becomes an unjointed portion Pu (in other words, when an unjointed portion Pu occurs at the peripheral portion Re of the two joining targets 101 and 102).

[0049] Specifically, the first support portion 61 is composed of a main body portion 611, an annular portion 612, and a beam portion 613. Here, the main body portion 611 is the part that contacts the central region of the back surface 101b of the object to be joined 101, which is inside the peripheral edge portion Re (see Figure 4(A)). The annular portion 612 is the part that contacts the annular region of the back surface 101b of the object to be joined 101, which includes the outer edge and is narrower than the peripheral edge portion Re (see Figure 4(A)). The beam portion 613 is the part that connects the annular portion 612 to the main body portion 611 at least in one place (see Figure 4(B)). The region enclosed by the main body portion 611, the annular portion 612, and the beam portion 613 forms the window 61w of the first support portion 61. In the example shown in Figure 4(B), the annular section 612 is connected to the main body 611 at four points by four beam sections 613 arranged at equal intervals around the center point of the first support section 61, resulting in the formation of four windows 61w. Note that the configuration of the first support section 61 (shape and number of windows 61w, etc.) is not limited to that shown in Figure 4(B) and can be appropriately changed according to the shape of the unjointed section Pu that occurs in the joint target section Pt.

[0050] The laser light source 7 is the part that emits laser light and can irradiate the joining targets 101 and 102, which are supported by the support mechanism 6, with laser light through the window 61w of the first support part 61. Specifically, the laser light source 7 can irradiate the unjointed portion Pu visible through the window 61w of the first support part 61 with laser light. In addition, the laser light source 7 can scan the laser light in a horizontal plane along the pattern shape of the unjointed portion Pu (in this case, the pattern shape of the annular linear portion Pt2). Furthermore, the laser light source 4 can focus the laser light on the joining point (the position of the unjointed portion Pu) between the joining targets 101 and 102.

[0051] The control unit 8 consists of processing units such as a CPU and a microcomputer, and controls various operating parts (support mechanism 6, laser light source 7, etc.) of the bonding and repair device. Specifically, the bonding and repair method is carried out by the control unit 8 performing control according to the following flow.

[0052] The control unit 8 first supports the objects to be joined 101 and 102 with the support mechanism 6 (support step; see Figure 4(A)). At this time, the objects to be joined 101 and 102 are positioned such that at least a portion of the unjointed portion Pu is visible through the window 61w of the first support portion 61, as shown in Figure 5(A). At this time, the control unit 8 may control the support mechanism 6 to clamp the objects to be joined 101 and 102 between the first support portion 61 and the second support portion 62.

[0053] Subsequently, the control unit 8 controls the laser light source 7 to irradiate the unjointed portion Pu visible through the window 61w of the first support portion 61 with laser light (repair step). At this time, the control unit 8 scans the laser light in a horizontal plane along the pattern shape of the unjointed portion Pu (in this case, the pattern shape of the annular linear portion Pt2). This repairs the bonding state of the portion of the unjointed portion Pu visible through the window 61w of the first support portion 61. In this way, a bonding repair method for repairing the bonding state of the unjointed portion Pu is performed by the bonding repair device.

[0054] This type of joint repair method allows heating to be limited to the unjointed Pu portion by using laser light. As a result, it is possible to repair the joint state of the unjointed Pu portion while preventing adverse effects from heat and light on parts other than the unjointed Pu portion.

[0055] Furthermore, the first support portion 61 allows the periphery of the unjointed portion Pu visible through the window 61w to be supported by the edge of the window 61w (main body portion 611, annular portion 612, beam portion 613), thereby increasing the degree of contact between the two joining targets 101 and 102 in the unjointed portion Pu. Therefore, by irradiating the unjointed portion Pu visible through the window 61w with laser light, it becomes possible to restore the joining state of the unjointed portion Pu to a good condition.

[0056] [3] Variant [3-1] First variation In the repair step of the joint repair method described above, the portion of the unjointed Pu visible through the window 61w of the first support portion 61 can be irradiated with laser light, but the portion of the unjointed Pu hidden by the beam portion 613 cannot be irradiated with laser light, and the joint state of that portion cannot be repaired (see Figure 5(A)).

[0057] Therefore, after the repair step is performed, the objects to be joined 101 and 102 may be rearranged by rotating them circumferentially, as shown in Figure 5(B), so that the portion of the unjointed Pu that was hidden by the beam portion 613 is visible through the window 61w. In Figure 5(B), the repaired portion of the unjointed Pu is shown by a thick solid line. The repair step described above may then be performed again on the portion of the unjointed Pu that was hidden by the beam portion 613.

[0058] With this joint repair method, even if the joint state cannot be repaired in all parts of the unjointed Pu in a single repair step, it becomes possible to repair the joint state in all parts of the unjointed Pu by rearranging the joining targets 101 and 102 and running the repair step again. Furthermore, such re-execution of the repair step can be repeated by rearranging the joining targets 101 and 102 each time until the joint state can be repaired in all parts of the unjointed Pu.

[0059] Furthermore, the joint repair method of this modified example may be appropriately modified so that, instead of rotating and rearranging the joint targets 101 and 102 in the circumferential direction, the first support portion 61 of the joint repair device is rotated in the circumferential direction (in other words, the joint targets 101 and 102 are rotated in the circumferential direction relative to the first support portion 61), allowing the portion of the unjointed portion Pu that was hidden by the beam portion 613 to be visible through the window 61w.

[0060] [3-2] Second variation As mentioned above, possible reasons for the occurrence of unjointed Pu include foreign matter getting stuck between the two joining targets 101 and 102, preventing them from adhering properly, or insufficient power from the laser light source 4 due to a temporary lack of output, resulting in insufficient laser light power for joining. On the other hand, unlike the embodiment described above (i.e., when it is clear that the portion of the joining target Pt held by the holding portion becomes unjointed Pu), it is unclear at the completion of the joining process whether unjointed Pu has actually occurred, and even if it has occurred, it is unclear where it is located.

[0061] Therefore, even if unjointed areas of Pu may occur for these reasons, the inventors further propose the following joint repair method to enable the formation of a good joint state between the joining targets 101 and 102.

[0062] First, the bonding state of the target Pt portion after the bonding process is inspected to identify any unbonded Pu portions in that target Pt portion (identification step). Next, the bonding state of the unbonded Pu portions identified in the identification step is repaired by irradiating them with laser light (repair step).

[0063] As a specific example, consider the case where, when the bonding process is performed using the bonding apparatus shown in Figure 2(A), an unbonded area of ​​Pu occurs in the region where pressurization by the pressure transmission medium 30 is possible (the region where laser light can be irradiated; in other words, the region other than the area where laser light irradiation is obstructed by the presence of the sealing mechanism 2 including the holding part 22).

[0064] First, let's consider the case where the cause of the unjointed Pu is insufficient laser power. In this case, after identifying the unjointed Pu in a specific step, the joining equipment used in the joining process (see Figure 2(A)) is used again to clamp the joining targets 101 and 102 (pressure step). Then, in the repair step, the unjointed Pu can be repaired by irradiating it with laser light while the insufficient laser power has been resolved.

[0065] Next, consider the case where the cause of the unjoined area Pu is a foreign object (inclusion) sandwiched between the joining targets 101 and 102. In this case, after the joining process is executed, a bulge will appear on the back surface 102b of joining target 102, with the location of the inclusion as its apex. By observing the back surface 102b of joining target 102 with a camera, such a bulge can be observed as interference fringes. Therefore, in a specific step, by observing the back surface 102b of joining target 102 with a camera, the portion of the joining target Pt that overlaps with the interference fringes observed by the camera can be identified as the unjoined area Pu. Furthermore, the center position of the interference fringes can be identified as the location of the inclusion.

[0066] In this case as well, the bonding state of the unbonded Pu can be repaired by using the bonding equipment (see Figure 2(A)) that was used in the bonding process. On the other hand, since the cause of the unbonded Pu is an inclusion, it cannot be removed, and therefore the bulge with the inclusion as its apex cannot be eliminated. Furthermore, if an inclusion is located on the unbonded Pu, it is difficult to improve the bonding state of the unbonded Pu even if laser light is directly irradiated onto the unbonded Pu caused by the inclusion.

[0067] Therefore, before performing the repair step, a pressure greater than the pressure applied to the back surface 101b of the object to be joined 101 during the clamping of the objects to be joined 101 and 102 in the joining process is applied by the pressure transfer medium 30 (pressurization step). This makes it possible to shrink the bulge as much as possible and increase the area of ​​contact between the objects to be joined 101 and 102 around the inclusion.

[0068] Then, in the repair step, while maintaining the state in which the bulge has been contracted as much as possible by the pressurizing step, the bonding state of the unbonded Pu is repaired by irradiating it with laser light while avoiding the location of the inclusion identified in the specific step.

[0069] In this case, if the inclusion is located in a position offset from the unjointed Pu portion, the pressure step described above minimizes the swelling and reduces the influence of the inclusion, and then the bonding state of the unjointed Pu portion can be restored by directly irradiating the unjointed Pu portion with laser light.

[0070] On the other hand, if the inclusion is located on the unjoined Pu portion, the laser beam is irradiated to a position offset from the unjoined Pu portion, avoiding the location of the inclusion. This offset position allows for bonding at the offset location, thereby complementing the repair of the bonding state in the unjoined Pu portion. As an example, as shown in Figure 6(A), the bypass portion Pt3, which bypasses the location of the inclusion, is reset as the bonding target portion Pt. By irradiating this bypass portion Pt3 with laser beam, the repair of the bonding state in the unjoined Pu portion can be complemented. In Figure 6(A), the portion of the bonding target portion Pt where bonding has been completed is shown with a thick solid line (the same applies to Figure 6(B)). As another example, as shown in Figure 6(B), another linear section Pt4 can be reconfigured as the joining target section Pt along a portion of the joining target section Pt that includes the unjoined section Pu (including the section where joining has already been completed), and by irradiating this linear section Pt4 with laser light, the repair of the joining state in the unjoined section Pu can be supplemented (see Figure 6(B)).

[0071] Furthermore, the irradiation of the unjointed Pu with laser light performed in the repair step includes not only cases where the unjointed Pu is directly irradiated with laser light to repair the bonding state of the unjointed Pu, but also cases where, even if the laser light is not directly irradiated with laser light, it is necessary to avoid inclusions, and the repair of the bonding state in the unjointed Pu can be supplemented by irradiating the laser light at a position offset from the unjointed Pu while avoiding the inclusions.

[0072] [3-3] Third variation If the cause of the unjointed Pu is a foreign object (inclusion) sandwiched between the objects to be joined 101 and 102, as a method for repairing the joining state of the unjointed Pu, in the second modified example described above, a pressurizing step is performed before the repair step to shrink the bulge caused by the inclusion as much as possible and increase the area of ​​contact between the objects to be joined 101 and 102 around the inclusion. However, instead of the pressurizing step, or in parallel with the pressurizing step, the following pre-treatment step may be performed.

[0073] Specifically, before performing the repair step, the inclusion located at a specific position is irradiated with pre-treatment laser light to heat and deform the inclusion, or sublimate it through phenomena such as ablation (pre-treatment step). This reduces the height of the bulge, and as a result, the contact area between the bonding targets 101 and 102 around the inclusion can be increased.

[0074] Furthermore, when the inclusions are heated and deformed with laser light in the pretreatment step, performing the pressurization step in parallel allows the heated inclusions to be pressed down with pressure and deformed efficiently, resulting in a reduction in the height of the bulge.

[0075] Furthermore, when sublimating inclusions with laser light in the pretreatment step, performing a pressurization step in parallel allows the gas generated by sublimation to be pushed into the cavity by pressure, thereby eliminating the bulge. If the bulge can be eliminated, in the repair step, it becomes possible to irradiate the unbonded Pu directly with laser light without avoiding the inclusions.

[0076] The above-described embodiments and modifications should be considered in all respects to be illustrative and not restrictive. The scope of the present invention is indicated by the claims, rather than by the above-described embodiments and modifications. Furthermore, the scope of the present invention is intended to include all modifications within the meaning and scope equivalent to the claims.

[0077] Furthermore, from the above-described embodiments and modifications, each step constituting the joint repair method may be individually extracted as the subject of the invention, or a joint repair device used in the joint repair method, or each part of the joint repair device (such as the first support part 61), may be individually extracted. Alternatively, a combination of these with a joint process or a part of the joint device may be extracted as the subject of the invention. [Explanation of Symbols]

[0078] 1. Chamber mechanism 2. Seal mechanism 3. Pressurization mechanism 4. Laser light source 5. Control Unit 6 Support mechanism 7. Laser light source 8 Control Unit 10 Chambers 11. First Chamber Component 12 Second Chamber Component 13 Drive unit 21 Guard section 22 Holding part 30 Pressure transmission medium 61 1st support part 61w window 62 Second support part Ct cutting line Pt joint target area Pu unbonded part R1 First Chamber Region R2 Second Chamber Region Rd device area Re Peripheral area 101, 102 Joining targets 101a, 102a Opposite surface 101b, 102b back 103 Indentation 104 elements 111 First cylindrical section 112 Stage 1 121 Second cylindrical section 122 Stage 2 123 Drive unit 611 Main body 612 Ring section 613 Beam section Pt1, Pt2, Pt4 Linear part Pt3 detour section

Claims

1. In a joining process in which two objects to be joined are joined at a joining target area set within their opposing surfaces, if an unjoined area occurs in at least a part of the joining target area, a joining repair method is provided in which the joining state at the unjoined area is repaired by irradiating the unjoined area with laser light. The support step involves supporting the two objects to be joined by sandwiching them between a first support portion and a second support portion from their back sides, wherein the first support portion is a support portion that allows at least a part of the unjoined portion to be seen through a window for passing laser light, After the support step, a repair step is performed to repair the bonding state at the unbonded portion by irradiating the unbonded portion with laser light through the window, Includes, A joint repair method in which, when the unjointed portion occurs at the periphery of the two objects to be joined, the first support portion includes a main body portion that contacts the central region of the back surface inward from the periphery, an annular portion that contacts the annular region along the outer edge of the back surface, and a beam portion that connects the annular portion to the main body portion, wherein the region enclosed by these portions is the window.

2. The joint repair method according to claim 1, wherein after performing the repair step, the two joint targets are rotated circumferentially relative to the first support so that the portion of the unjointed area that was hidden by the beam is visible through the window, and then the repair step is performed again on that portion.

3. A bonding repair method in which two objects to be bonded are bonded at a bonding target portion set on their opposing surfaces, wherein if an unbonded portion occurs in at least a part of the bonding target portion, the bonding state at the unbonded portion is repaired by irradiating the unbonded portion with laser light. A pressurizing step in which pressure is applied to the back surface of one of the two objects to be joined, with a gas or liquid acting as a pressure transmission medium in direct contact, and the pressure is received by a support on the back surface of the other object to be joined, thereby clamping the two objects to be joined together. A repair step in which, while pressing the two objects to be joined together by the pressurization step, laser light is irradiated onto the unjointed portion from the back side of one of the objects to be joined, thereby repairing the joining state at the unjointed portion, A method of repairing a bond, including a method of joining and repairing a joint.

4. The aforementioned pressurizing step is also used in the bonding process, The bonding repair method according to claim 3, wherein in the pressurizing step performed when repairing the unbonded portion, a pressure greater than the pressure applied in the pressurizing step performed before the repair is applied to the back surface of one of the objects to be bonded, using a gas or liquid pressure transmission medium.

5. A selection step to identify the unjoined portion in the target joint by inspecting the joining state at the target joint after the joining process, A repair step in which the bonding state at the unbonded portion identified in the specified step is restored by irradiating the unbonded portion with laser light, A joint repair method according to any one of claims 1 to 4, including the following:

6. A bonding repair method in which two objects to be bonded are bonded at a bonding target portion set on their opposing surfaces, wherein if an unbonded portion occurs in at least a part of the bonding target portion, the bonding state at the unbonded portion is repaired by irradiating the unbonded portion with laser light. A selection step to identify the unjoined portion in the target joint by inspecting the joining state at the target joint after the joining process, A repair step in which the bonding state at the unbonded portion identified in the specified step is restored by irradiating the unbonded portion with laser light, Includes, In the aforementioned identification step, the unjointed portion is identified, and if the cause of the unjointed portion is an inclusion, the location of the inclusion is identified. A bonding repair method comprising the repair step of repairing the bonding state at the unbonded portion by irradiating laser light while avoiding the location of the inclusion identified in the identification step.

7. A bonding repair method in which two objects to be bonded are bonded at a bonding target portion set on their opposing surfaces, wherein if an unbonded portion occurs in at least a part of the bonding target portion, the bonding state at the unbonded portion is repaired by irradiating the unbonded portion with laser light. The identification step involves inspecting the bonding state at the target bonding portion after the bonding process to identify the unbonded portion that occurred at the target bonding portion, and, if the cause of the unbonded portion is an inclusion, to identify the location of the inclusion. A pre-treatment step in which the inclusion at the location identified in the specified step is irradiated with laser light to deform or sublimate the inclusion, After the pre-processing step, a repair step is performed to repair the bonding state at the unbonded portion identified in the specific step by irradiating it with laser light, A method of repairing a bond, including a method of joining and repairing a joint.

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