JP4154379B2 - Interelectrode bonding method and structure between substrates - Google Patents

Description

TECHNICAL FIELD The present invention relates to bonding between substrates, which have bonding strength and electrical bonding at the same time, by bonding between electrode ends of minute (micro) circuits or the like provided on different substrates, that is, bonding between bumps and pads. .

Conventional technology

In recent years, with the increase in functionality and miniaturization and weight reduction of MEMS (Micro-Electronic-Micro-System), the elements themselves have become more complex, making it difficult to manufacture. For this reason, there is an increasing need to fabricate the electronic circuit and the MEMS on different substrates, and then electrically bond the circuit wiring electrodes of the two substrates together and simultaneously integrate the two substrates. However, in bonding between substrates, it has been difficult to bond all the minute circuit wiring electrodes formed on both substrates simultaneously with a high yield.

For example, when flip chip bonding is performed, if there are variations in bumps, the first semiconductor chip mounted on the second semiconductor chip is tilted and misaligned. Such misalignment also causes a decrease in connection reliability, and thus requires a flattening process in which bump heights are aligned in advance (see Patent Document 1).

In another proposal, a protrusion made of a metal is provided at a terminal extraction position of a semiconductor chip, while a solder bump is provided on a pad of a circuit board on which the semiconductor chip is mounted, and the protrusion is aligned with the solder bump. Is formed by flip chip bonding in which a semiconductor chip and a circuit board are connected by solder including a protrusion at the center (see Patent Document 2).
Japanese Patent Laid-Open No. 11-017103 JP 7-169790 A

However, the flattening process for aligning the heights of the bumps made of Au metal disclosed in Patent Document 1 described above is expected to be effective when the number of bumps is as small as two or three. However, if the number of bumps is extremely large, for example, if the number of bumps is 1000 or more, it can be said that it is bothersome and unnecessary. That is, according to the experiment by the inventors of the present invention, the height distribution of the bumps formed by plating with a target height of 15 μm was a Gaussian distribution, and the dispersion (σ) value was about 0.12 μm. Since the hardness of Au used as a bump material is low (Vickers hardness is about 50), the plastic deformability is good, so that it was not necessary to perform a flattening process before joining the electrodes between the substrates. Rather, when the load applied between the substrates is large at the time of inter-electrode bonding between the substrates, the bumps are greatly deformed, and this large deformation causes an electrical short circuit between adjacent electrode bumps in the case of high-density mounting. There was a fear that it would occur.

In the configuration disclosed in Patent Document 2 described above, a protrusion made of metal is provided on the terminal of the semiconductor chip, and the protrusion and the solder bump are heated and solidified to perform inter-electrode bonding between the substrates.・ Because it has a melting process, distortion occurs due to internal stress due to the difference in coefficient of linear expansion between the substrates that are integrally bonded in the temperature-decreasing process up to room temperature after bonding, which affects the dimensional accuracy and causes peeling. There is a fear.

In view of the above-described problems, the interelectrode bonding method between substrates of the present invention is an electrode bump that is a portion that contributes to bonding in a plastic deformation process in which the height decreases and is electrically connected to a conductor portion. The reinforcing bumps and stopper bumps formed on the insulator portion, which are parts that contribute to the joining in the plastic deformation process in which the height decreases, are formed and contacted with the corresponding electrode bumps on the second substrate The electrode pad electrically connected to the conductor portion, the portion that contacts the corresponding reinforcing bump, the reinforcing pad formed on the insulator portion, and the first contacted to the corresponding stopper bump the height to form a stopper pad, which serves as the after low Ku and stopper than the reinforcing bump and the electrode bump is pushed only the stopper bump defining the substrate and the bonding distance between the second substrate The electrode bumps and the electrode pads, the reinforcing bumps and the reinforcing pads, and the stopper bumps and the stopper pads are aligned and aligned with each other, and the electrode bumps and the electrode bumps are applied while applying a load. The reinforcing bumps are deformed, and the electrode bumps and the electrode pads and the reinforcing bumps and the reinforcements are reinforced by deforming the electrode bumps and the reinforcing bumps until the stopper bumps and the stopper pads come into contact with each other, come into contact with each other, and are pressed against each other. A pad is joined, and the electrodes between both substrates are joined by the joining.

In addition, in view of the above problems, the inter-electrode joint structure of the present invention is a part that contributes to joining in the plastic deformation process in which the height decreases, and the electrode bump that is electrically connected to the conductor part, the height allowed but is deformed to reinforcing bump height is pushed after formation serves as a low Ku and stopper than the reinforcing bump and the electrode bump a portion contributing to the junction with decreasing the plastic deformation process is formed on the insulator portion Further , the first substrate on which the stopper area is larger than that of the electrode bumps and the reinforcing bumps, and the corresponding portion is in contact with the corresponding electrode bump and electrically connected to the conductor portion. The electrode pads that are in contact with the corresponding reinforcing bumps, the reinforcing pads formed on the insulator, and the corresponding stopper bumps. A second substrate on which a stopper pad for defining a bonding interval between the substrate and the second substrate is formed, and the corresponding electrode bump and electrode pad and the corresponding reinforcement bump and reinforcement pad are overlapped with each other and aligned. The bonding interval between the two substrates is defined by bringing the corresponding stopper bump and the stopper pad into contact with each other and bringing them into contact with each other. It is characterized by being joined.

According to the present invention, one substrate is provided with a stopper pad that serves as a stopper, and the other substrate is provided with a stopper bump that serves as a stopper, thereby preventing an excessive load from being applied during bonding. Is done. Further, since there is no heating / melting process, there is little risk of distortion due to internal stress caused by a difference in linear expansion coefficient between the substrates.

An embodiment of the present invention will be described. In one embodiment of the electrode joining structure or bonding method between the substrates of the present invention, the first (or second) Si substrate having a MEMS consisting minute dimensional, MEMS driving unit electrically connected Forming electrode bumps, reinforcing bumps to reinforce bonding strength, stopper bumps serving as stoppers and alignment marks, and circuit wiring and circuit wiring on the second (or first) Si substrate Electrode pads that are electrically coupled to each other, reinforcing pads to reinforce the bonding strength, stopper pads that contact the stopper bumps during bonding, and alignment marks are formed, and prior to bonding between the electrodes between the two substrates, A load is applied only to the stopper bump, and the height of the stopper bump is adjusted to a height that functions as a stopper by utilizing plastic deformation caused by the load application. Furthermore, in order to make the bumps that are not necessary in advance, the bumps are lowered by plastic deformation to a height at which only the bumps are not joined, that is, below the height of the stopper bumps. Then, both Si surfaces are cleaned by bombardment with ions such as Ar ions or neutralized Ar ions that are not charged. Here, the sectional area in the plane per stopper bump is set larger than that of the electrode bump and the reinforcing bump.

After that, at room temperature, both Si substrates are overlapped with each other, both Si substrates are aligned using alignment marks, and a constant load is applied from both sides of both Si substrates. By applying this load, the corresponding bump and pad can be firmly bonded to each other by the interatomic interaction. The distance between the substrates in the joined state is defined by the contact between the stopper bump and the stopper pad, which hardly deforms when a constant load is applied.

Bonding between electrodes of both Si substrates is performed by the above method. By applying the load, the electrode bumps and the reinforcing bumps are gradually plastically deformed, and the height is reduced. When the height reaches the height of the stopper bumps, the electrode bumps and the reinforcing bumps are plastically deformed. Stops. The bumps that have been made non-functional in advance do not contribute to the bonding in this load application process. This bonding completes the interelectrode bonding and electrical connection between the substrates.

However, since the circuit wiring board (or MEMS substrate) on which the circuit wiring (or MEMS) is formed has a Si oxide film only on one surface, internal stress is inherently present, and therefore the circuit wiring (or MEMS) It warps in a convex shape toward the Si oxide film side on which is formed. Therefore, after bonding, there is a concern that the internal stress peels off the electrode bump / electrode pad bonding pair disposed on the peripheral edge of the substrate. In order to eliminate this concern, reinforcing bumps and reinforcing pads may be arranged in advance on the outer periphery of the electrode bumps and electrode pads on both substrates. By this reinforcement bump / reinforce pad bonding, peeling between the electrode bump / electrode pad due to internal stress can be reliably prevented.

In the above configuration, the bump and the pad can be formed of a material having plastic deformability, preferably a metal material such as Au, Cu, or Al having a face-centered cubic crystal, or a metal material such as low-melting point In or Sn. Electrodes and reinforcing bumps and pads are easy to make if they have the same shape, and if the cross-sectional area is small, they are easy to join. Stopper bumps and pads that hardly deform under a certain load due to their roles can be formed of a metal material having face-centered cubic crystals, Si, glass, or the like. For this purpose, this cross-sectional area is preferably set to be considerably larger (for example, by an order of magnitude) than the cross-sectional area of the electrodes and reinforcing bumps.

In order to increase the strength of the reinforcing bumps, the number of reinforcing bumps should be increased. For example, by making the bump dimensions the same for bumps formed by plating, effective room-temperature bonding can be achieved by applying a low load. Further, a substrate other than the Si substrate can be used, but if Si is used, circuit wiring and MEMS can be easily built and mounted on the substrate.

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.
(First embodiment)
1, 2, 3, 4, 5, 6, and 7 are cross-sectional views that clearly represent the features of the first embodiment of the inter-electrode bonding structure or bonding method according to the present invention. is there. In the figure, 1 is the first Si substrate, 4 is the Si oxide film formed on the Si substrate 1, 5 is the electrode bump made of Au formed on the Si substrate 1, and 6 is the reinforcement made of Au formed on the Si substrate 1. Bump, 7 is a stopper bump made of Au formed on the Si substrate 1, 8 is a second Si substrate, 9 is a Si oxide film formed on the Si substrate 8, 10 is an electrode pad made of Au formed on the Si substrate 8, 11 is a reinforcing pad made of Au formed on the Si substrate 8, and 12 is a stopper pad made of Au formed on the Si substrate 8. In FIG. 2, 13 is a pressing plate for pushing the stopper bump 7 to a predetermined height, and 14 is an applied load for plastically deforming the stopper bump 7 to a predetermined height. Further, in FIG. 4, reference numeral 15 denotes an applied load for joining the first Si substrate 1 and the second Si substrate 8.

In the above configuration, the Si oxide film 4 is formed on the first Si substrate 1, circuit wiring (not shown) is formed on one surface of the Si oxide film 4, and the circuit wiring is formed by a photolitho process and a plating process. Electrode bumps 5 are formed on the upper surface, and reinforcing bumps 6 and stopper bumps 7 are formed on the Si oxide film 4 to the same height by Au plating. Thereafter, as shown in FIG. 2, the stopper bump 7 is pushed through the pressing plate 13 with the applied load 14. In this pushing process, the stopper bump 7 is deformed to a predetermined height by plastic deformation. By this indentation, Au, which is a metal material having face-centered cubic crystals, is crushed and work hardened, and after that, even if it comes into contact with a stopper pad described later, it does not deform so much. On the other hand, an electrode electrically coupled to a MEMS drive electrode terminal (not shown) on the second Si substrate 8 on which MEMS (not shown) is formed by the photolithographic process and the plating process in the same manner as described above. The pad 10, the reinforcing pad 11, and the stopper pad 12 are respectively formed to the same height by batch plating of Au.

Next, the surfaces of both Si substrates are cleaned by Ar ion bombardment, and then the first Si substrate 1 and the second Si substrate 8 are opposed to each other, and corresponding electrode bumps are made using alignment marks (not shown). 5 and the electrode pad 10, the reinforcing bump 6 and the reinforcing pad 11, and the stopper bump 7 and the stopper pad 12 are aligned and overlapped. Then, an applied load 15 is applied from both sides of both Si substrates 1 and 8 as shown in FIG. By this operation, the electrode bump 5 and the reinforcing bump 6 continue to undergo plastic deformation until the height of the stopper bump 7 is reached, and when the height of the stopper bump 7 is reached, the plastic deformation stops. That is, the height of the electrode bump 5 and the reinforcing bump 6 is equal to the height of the stopper bump 7. Therefore, by setting the height of the stopper bump 7 to an arbitrary predetermined height by this method in advance, excessive deformation of the electrode bump 5 can be prevented, and an electrical short circuit between adjacent electrode bumps 5 can be prevented. I can do it.

When the aspect ratio of the stopper bump 7 (aspect ratio; height of bump / length of one side of the bump) is smaller than the aspect ratio of the electrode bump 5 and the reinforcing bump 6, the stopper bump 7 acts as a stopper. According to the experiment of this example, when the bump is pressed with an equivalent stress, the plastic deformability of the bump decreases as the aspect ratio decreases. By utilizing this phenomenon, a bump having a reduced aspect ratio is used as the stopper bump 7.

In this embodiment, the electrode bumps 5 and the reinforcing bumps 6 are both 19 μm square and 15 μm in height, and are formed by batch Au plating. The number of the electrode bumps 5 and the reinforcing bumps 6 is 2048 each. And 380. The thickness of the pad is about 0.2 μm. The stopper bump 7 is approximately 120 μm square. If the cross-sectional area of the stopper bump 7 is about three times the area of the electrode bump 5 and the reinforcing bump 6, it acts as a stopper. The applied load 15 applied when bonding both the Si substrates 1 and 8 was 50 [kgf].

In this embodiment, the electrode bump 5, the electrode pad 10, the reinforcing bump 6, the reinforcing pad 11, the stopper bump 7 and the stopper pad 12 are all made of metallic material Au, and any of these bumps It was produced at the same time in the Au plating process. However, other than Au, a face-centered cubic metal material that is easily plastically deformed may be used. For example, Cu or Al may be used. In addition, low melting point metals In and Sn that are easily deformed and easily joined may be used. Further, the bump and the pad may be made of different materials. Further, the stopper may be glass, Si or the like. However, if these are made of the same material, it will be easy to make them all at once.

Since both the Si substrates 1 and 8 have the Si oxide film 9 having a thickness of 1.5 μm only on one side, they are curved in a convex shape toward the Si oxide film side. When the curved Si substrate 1 and the Si substrate 8 are bonded together by the above method, both the Si substrates 1 and 8 are firmly bonded without being peeled off by the internal stress of the Si oxide films 4 and 9 after bonding. It was. That is, a strong interelectrode bonding between the substrates was obtained. This bonding was performed at room temperature, and no thermal internal stress was generated by the bonding.

As shown in FIGS. 5, 6, and 7, the stopper bump 7 and the stopper pad 12 were also provided as stoppers even in the case of the modified examples in which the central portions and the end portions of the Si substrates 1 and 8 were respectively provided. .

In the above-described embodiments and modifications, when an electric signal (not shown) is input from the electrode terminal (not shown) of the first Si substrate 1 having circuit wiring after inter-electrode bonding between the substrates, the second Si substrate is obtained. The MEMS element (not shown) formed on 8 was driven as specified. Although it is easier to form pads on the second Si substrate on which the MEMS element is formed, it is also possible to form high bumps on the second Si substrate on which the MEMS element is formed.

(Second embodiment)
8, FIG. 9, FIG. 10, and FIG. 11 are drawings that clearly show the features of the second embodiment of the inter-electrode bonding structure or bonding method between substrates of the present invention. In the figure, 1 is a first Si substrate on which a MEMS element (not shown) is formed, 2 is a flat portion of the Si substrate 1, 3 is a groove portion of the Si substrate 1, 4 is a Si oxide film of the Si substrate 1, and 5 is Electrode bumps made of Au formed on electrode terminals (not shown) electrically coupled to MEMS elements on the Si substrate 1, 6 reinforced bumps made of Au formed on the Si substrate 1, and 7 on the Si substrate 1 Stopper bumps made of Au, 8 is a second Si substrate on which circuit wiring (not shown) for driving the MEMS element is formed, 9 is a Si oxide film formed on the surface of the Si substrate 2, and 10 is the circuit An electrode pad made of Au electrically coupled to the electrode terminal of the wiring, 11 is a reinforcing pad made of Au formed on the Si substrate 2, 12 is a stopper pad made of Au formed on the Si substrate 2, and 15 is the first Applied load for bonding the Si substrate 1 and the second Si substrate 8, 16 is a mark for plastically deforming the stopper bump 7 to a predetermined height. Load, pressing plate for pressing the stopper bumps 7 17, 18 protrusions of the pressing plate 17, 19 is a concave portion of the pressing plate 17.

In the above configuration, a Si oxide film 4 is formed on one surface of the Si substrate 1 by sputtering, and a MEMS element (not shown) is formed on the Si oxide film 4 using a semiconductor photolithographic process. The electrode terminals (not shown) connected to each other are formed by forming an Au thin film. Further, by using a photolithographic process and a plating process, the electrode bumps 5 are formed on the electrode terminals, and the reinforcing bumps 6 and the stopper bumps 7 are formed on the Si oxide film 4 by batch Au plating. The height of the Au plating at this time is 12 μm. Thereafter, as shown in FIG. 9, the convex portion 18 of the pressing plate 17 is pressed against the stopper bump 7 and is pressed with the applied load 16. In this pushing process, the stopper bump 7 is plastically deformed to a predetermined height of 6 μm.

The Si substrate 1 on which the MEMS (not shown) is formed is forced to have a surface shape rich in steep irregularities as shown in FIG. 10 by forming the MEMS element. For this reason, it is difficult to form a wiring for driving the MEMS on the same substrate because of a risk of causing a disconnection of the wiring. Therefore, circuit wiring for driving the MEMS element is provided on another Si substrate 8.

An Si oxide film 9 is also formed on the Si substrate 8 by sputtering, and an electric circuit wiring (not shown) for driving the MEMS is formed on the Si oxide film 9 by using a semiconductor photolithographic process and a thin film forming process. Form. Further, the electrode pad 10 is formed on the terminals of the electric circuit wiring, and the reinforcing pad 11 and the stopper pad 12 are formed on the Si oxide film 9 by Au thin film formation.

After forming both Si substrates 1 and 8, the bonding surfaces of both Si substrates are cleaned by Ar ion bombardment, and then Si substrate 1 and Si substrate 8 are opposed to each other, using alignment marks (not shown) Align the electrode bump 5 and electrode pad 10, the reinforcing bump 6 and the reinforcing pad 11, and the stopper bump 7 and the stopper pad 12, respectively, and superimpose both Si substrates 1 and 8 on both sides of both Si substrates 1 and 8. As shown in 11, apply load 15 is applied. By this operation, the electrode bump 5 and the reinforcing bump 6 continue to be plastically deformed until the height of the stopper bump 7 is reached, and the plastic deformation stops when the height of the stopper bump 7 is reached. That is, the height of the electrode bump 5 and the reinforcing bump 6 in the joined state is equal to the height of the stopper bump 7.

Accordingly, by setting the height of the stopper bump 7 to an arbitrary predetermined height in advance by the above method, excessive deformation of the electrode bump 5 can be prevented, and at the same time, an electrical short circuit between adjacent electrode bumps can be prevented. I can do it. In this embodiment, the electrode bump 5, the reinforcing bump 6 and the stopper bump 7 are formed by Au plating, and the height is about 12 μm. The planar shapes of the electrode bump 5, the reinforcing bump 6, and the stopper bump 7 are 19 μm square, 19 μm square, and 120 μm square, respectively. The material of the electrode bump 5, the electrode pad 10, the reinforcing bump 6, the reinforcing pad 10, the stopper bump 7, and the stopper pad 12 is all made of Au, which is a metal material. Thus, it is efficiently produced by the Au plating process.

Further, the interelectrode bonding between the substrates was performed at room temperature bonding at room temperature, and no thermal internal stress was generated by the bonding. Further, the Si substrates 1 and 8 are curved in a convex shape toward the Si oxide film due to residual stress when the Si oxide films 4 and 9 formed on one side are formed by 1.5 μm. Although 8 was bonded by the above method, both the Si substrates 1 and 8 were firmly bonded without being separated by the residual stress.

Also in the above embodiment, when an electrical signal (not shown) is input from the electrode terminal (not shown) of the Si substrate 1 having circuit wiring after the interelectrode bonding between the substrates, the MEMS element (not shown) formed on the Si substrate 8 is shown. None) could be driven as prescribed.

As described above, according to the embodiment of the present invention, since the stopper bump that plays the role of the stopper is provided, the adjacent electrode caused by excessive crushing of the electrode bump due to excessive application load at the time of joining In addition, it is possible to prevent the influence of variations in bump height, and at the same time, the bonding between the reinforcing bump and the reinforcing pad can be achieved without peeling the inter-electrode bonding between the substrates having residual stress. . Further, it is possible to avoid the bonding between the bumps / pads that do not need to be bonded by previously performing the non-functional process on the bumps.

The figure which shows the preparation method and structure of a bump and pad in the room temperature junction between the wiring electrodes between the boards concerning the 1st Example of this invention. The figure which shows the preparation methods of the stopper bump | vamp concerning the 1st Example of this invention. The figure which shows the matching state between the board | substrates concerning the 1st Example of this invention. The figure which shows the joining process between the board | substrates concerning the 1st Example of this invention. The figure which shows the preparation method and structure of the bump | vamp of one board | substrate in connection with the modification of the 1st Example of this invention. The figure which shows the matching state between the boards concerning the modification of the 1st Example of this invention. The figure which shows the joining process between the board | substrates concerning the modification of the 1st Example of this invention. The figure which shows the production method and structure of a bump and pad in the room temperature junction between the wiring electrodes between the boards concerning the 2nd Example of this invention. The figure which shows the preparation methods of the stopper bump | vamp concerning the 2nd Example of this invention. The figure which shows the matching state between the board | substrates concerning the 2nd Example of this invention. The figure which shows the joining process between the board | substrates concerning the 2nd Example of this invention.

Explanation of symbols

1: First substrate
8: Second board
5: Electrode bump
6: Reinforcement bump
7: Stopper bump
10: Electrode pad
11: Reinforcement pad
12: Stopper pad
13, 17: Press plate
14, 15, 16: Applied load

Claims (8)

The first substrate contributes to bonding in the plastic deformation process with decreasing height, and is an electrode bump electrically connected to the conductor part, and the portion that contributes to bonding in the plastic deformation process with decreasing height. Forming a reinforcing bump and a stopper bump formed on the insulator portion, and corresponding to an electrode pad that is in contact with the corresponding electrode bump and is electrically connected to the conductor portion on the second substrate. Reinforcing pads formed on the insulator part, which are in contact with the reinforcing bumps, and stopper pads that contact the corresponding stopper bumps and define the bonding interval between the first substrate and the second substrate. formed, thereafter, deformed to a height which functions as a low Ku and stopper than the reinforcing bump and the electrode bump is pushed only the stopper bumps, and opposite the two substrates, and the electrode bump The electrode bumps and the reinforcing bumps are deformed while applying a load while aligning the pole pads, the reinforcing bumps and the reinforcing pads and the stopper bumps and the stopper pads with each other, and the stopper bumps and the stopper pads contact each other. Then, the electrode bump and the reinforcing bump are deformed until they are in contact with each other and are pressed against each other, thereby joining the electrode bump and the electrode pad and the reinforcing bump and the reinforcing pad, and joining the electrodes between the two substrates by the joining. A method for interelectrode bonding between substrates, comprising: 2. The inter-electrode bonding method between substrates according to claim 1, wherein a bonding surface between the first substrate and the second substrate is cleaned. 3. The inter-electrode bonding method between substrates according to claim 1, wherein in order to avoid bonding between a bump and a pad that do not need to be bonded, the bump is rendered nonfunctional. 4. The inter-electrode bonding method between substrates according to claim 1, wherein the first substrate is a substrate having a convex portion and a concave portion. 5. The interelectrode bonding method between substrates according to claim 1, wherein the stopper bump is deformed to a height that functions as a stopper by being pushed in by a pressing plate having a convex portion pressed against the stopper bump. 6. The inter-electrode bonding method between substrates according to claim 1, wherein the reinforcing bump and the stopper bump are collectively formed by Au plating. 7. The inter-electrode bonding method between substrates according to claim 1, wherein a cross-sectional area of each stopper bump in a plane is larger than that of the electrode bump and the reinforcing bump . Electrode bumps that contribute to joining in the plastic deformation process where the height decreases and are electrically connected to the conductor part, and parts that contribute to joining in the plastic deformation process that reduces the height on the insulator part formed by being reinforced bumps, the cross-sectional area in the plane of more per one be deformed to a height that functions as a low Ku and stopper than the reinforcing bump and the electrode bump is pushed after formation than that of the electrode bumps and the reinforcing bump A first substrate on which a large stopper bump is formed, a portion that is in contact with the corresponding electrode bump and is electrically connected to the conductor portion, and a portion that is in contact with the corresponding reinforcing bump and is an insulator portion Reinforcing pad formed on top, stopper pad that contacts the corresponding stopper bump and defines the bonding interval between the first substrate and the second substrate The formed second substrate is joined by aligning and joining the corresponding electrode bump and electrode pad and the corresponding reinforcing bump and reinforcing pad to each other, and the joining interval between the substrates is increased. The inter-substrate junction structure characterized in that the corresponding stopper bump and the stopper pad are brought into contact with each other and brought into contact with each other, and the electrodes between the substrates are joined to each other by the joining. .

Images