Semiconductor device and semiconductor device manufacturing method

Abstract

To provide a semiconductor device of which reliability is improved by joining a wiring pattern and a terminal electrode without scattering fine metal powder, and a manufacturing method thereof.SOLUTION: A semiconductor device comprises an insulation substrate including a wiring pattern in a surface layer and a terminal electrode including a bag-shaped internal space including a terminal electrode tip end opening, and the terminal electrode is grounded in a self-standing state by being fitted with the wiring pattern. A semiconductor manufacturing device is a manufacturing method of a semiconductor device comprising an insulation substrate including a wiring pattern in a surface layer and a terminal electrode including a bag-shaped internal space including a terminal electrode tip end opening and includes fixing processing for performing position fixing at a position where the terminal electrode is engaged with the wiring pattern and plastic deformation processing for performing expansion until the terminal electrode is grounded in a self-standing state by being fitted with the wiring pattern.SELECTED DRAWING: Figure 3

Description

[Technical field]

[0001] The present disclosure relates to a semiconductor device and a method for manufacturing the same. [Background technology]

[0002] Patent Document 1 discloses ultrasonic bonding, which is one of the techniques for bonding a wiring pattern and a terminal electrode on an insulating substrate. In ultrasonic bonding, a load and ultrasonic vibration are applied to generate friction at the boundary surface, initiating a reaction. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] JP 2017-199713 A Summary of the Invention [Problem to be solved by the invention]

[0004] However, with the above-mentioned method, when friction occurs at the boundary surface between the wiring pattern and the terminal electrode, fine metal powder is scattered, which causes a problem of reduced reliability of the semiconductor device.

[0005] In order to solve the above-mentioned problems, the present disclosure aims to provide a highly reliable semiconductor device and a manufacturing method thereof by joining a wiring pattern and a terminal electrode without scattering fine metal powder. [Means for solving the problem]

[0006] A first aspect of the present disclosure is preferably a semiconductor manufacturing apparatus comprising an insulating substrate having a wiring pattern on a surface thereof, and a terminal electrode having a bag-shaped internal space with an opening at a tip end of the terminal electrode, the terminal electrode being configured to be grounded in a self-supporting state by engaging with the wiring pattern.

[0007] A second aspect of the present disclosure is a manufacturing method for a semiconductor device including an insulating substrate having a wiring pattern on a surface thereof and a terminal electrode having a bag-shaped internal space with an opening at a tip of the terminal electrode, the manufacturing method preferably including a fixing process for fixing the terminal electrode in a position where the terminal electrode interlocks with the wiring pattern, and a plastic deformation process for expanding the terminal electrode until the terminal electrode interlocks with the wiring pattern and is grounded in a self-supporting state. Effect of the Invention

[0008] According to the first and second aspects of the present disclosure, a highly reliable semiconductor device can be provided by bonding a wiring pattern and a terminal electrode without scattering fine metal powder. [Brief description of the drawings]

[0009] [Figure 1] 1 is a cross-sectional view showing a state before joining of a joint structure according to a first embodiment of the present disclosure. [Diagram 2] 1 is a plan view showing a state before joining of a joint structure according to a first embodiment of the present disclosure. [Diagram 3] 4 is a cross-sectional view showing a state after joining of the joint structure according to the first embodiment of the present disclosure. FIG. [Figure 4] 1 is a plan view showing a state after joining of a joint structure according to a first embodiment of the present disclosure. FIG. [Diagram 5] FIG. 11 is a plan view showing a state before joining of a joint structure according to a third embodiment of the present disclosure. [Figure 6] FIG. 11 is a cross-sectional view showing a state before joining of a joint structure according to a third embodiment of the present disclosure. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0010] First embodiment Prior to the description of the first embodiment, ultrasonic bonding, which is a conventional technique for bonding a wiring pattern and a terminal electrode on an insulating substrate, will be described. In ultrasonic bonding, first, the tip of the terminal electrode is placed on the wiring pattern on the insulating substrate. At this time, the tip of the terminal electrode is brought into contact with the wiring pattern. When a load and ultrasonic vibration are applied to the contact portion, the tip of the terminal electrode resonates, and friction occurs at the interface between the wiring pattern of the insulating substrate and the tip of the terminal electrode. This friction causes the oxide film on the surface of the interface to fly off, exposing a new surface. On the new surface, atomic motion is activated by heating due to frictional heat, and metal atoms move due to diffusion. This motion generates a mutual attraction between the metal atoms, so that the wiring pattern and the terminal electrode are bonded in a solid layer state.

[0011] As described above, ultrasonic bonding applies ultrasonic vibration together with a load. In other words, an ultrasonic oscillator generates a high-frequency alternating current to supply electrical energy to a transducer, which then converts the electrical energy into mechanical vibration and propagates it, thereby applying a load and vibration to the tip of the terminal electrode.

[0012] However, when the tip of the terminal electrode resonates and friction occurs between the tip and the wiring pattern of the insulating substrate, fine metal powder scatters, resulting in a problem of reduced reliability of the semiconductor device. For example, in the case of semiconductor devices that use large power, such as power semiconductors for electric railways or power generation, this is a particularly serious problem because there is a concern that the metal powder may induce insulation breakdown due to corona discharge. Therefore, the present disclosure aims to provide a semiconductor device that solves this problem.

[0013] FIG. 1 is a cross-sectional view showing a state before bonding of a joint structure according to a first embodiment of the present disclosure. The joint structure according to the first embodiment includes an insulating substrate 1. The insulating substrate 1 has a wiring pattern 1a including a convex shape on its surface and a ceramic substrate 1b inside. The wiring pattern 1a is made of aluminum (Al), copper (Cu), or an alloy thereof. The ceramic substrate 1b is made of alumina (Al 2 O 3 ), aluminum nitride (AlN) or silicon nitride (Si 4 N 4The insulating substrate 1 is made of an inorganic ceramic material such as SiO 2. The insulating substrate 1 is bonded to a heat sink 3 via a bonding material 2. A terminal electrode 4 is disposed directly above the wiring pattern 1a.

[0014] 2 is a plan view showing a state before joining of the joint structure according to the first embodiment of the present disclosure. The terminal electrode 4 has a bellows-shaped circuit pattern 4a at its tip, and the convex part of the bellows is in contact with the wiring pattern 1a by meshing with the convex part of the wiring pattern 1a. The terminal electrode 4 has a terminal electrode tip opening 4b at its tip, and has a bag-shaped internal space 4c on the inside from the opening. The terminal electrode 4 is made of Al or Cu, but the circuit pattern 4a does not have to be in a pure state of Al or Cu, and may be plated with nickel (Ni).

[0015] Although the embodiment in which the convex portions of the wiring pattern 1a and the circuit pattern 4a are alternately interlocked has been shown, any embodiment may be used as long as the terminal electrode 4 is grounded in an independent state after bonding. For example, the circuit pattern 4a may have a spiral convex shape.

[0016] A method for joining the terminal electrode 4 and the insulating substrate 1 according to the first embodiment will be described. First, a jig is used to fix the circuit pattern 4a and the wiring pattern 1a at a position where they mesh. Next, compressed air is injected into the internal space 4c from the terminal electrode tip opening 4b. The pressure of this compressed air is adjusted to, for example, 0.6 MPa to 0.8 MPa by passing through a pressure regulator.

[0017] The internal space 4c into which the compressed air is injected expands because the shape does not have an exhaust port. This expansion causes the tip of the terminal electrode 4 to plastically deform, causing a change in the pitch of the uneven shape of the bellows shape of the circuit pattern 4a. As a result, the clearance with the wiring pattern 1a is filled, and the terminal electrode 4 is grounded in a self-supporting state.

[0018] Fig. 3 is a cross-sectional view showing a state after joining of the joint structure according to the first embodiment of the present disclosure. Fig. 4 is a plan view showing a state after joining of the joint structure according to the first embodiment of the present disclosure. As described above, in the first embodiment, compressed air is injected from the terminal electrode tip opening 4b to expand the tip of the terminal electrode 4. As a result, the clearance between the circuit pattern 4a and the wiring pattern 1a is filled as shown in Fig. 3, so that the terminal electrode 4 is grounded in a self-supporting state.

[0019] Embodiment 2 The second embodiment has a joint structure similar to that of the first embodiment, but differs in that pure water is poured from the terminal electrode tip opening 4b.

[0020] A method for joining the terminal electrode 4 and the insulating substrate 1 according to the second embodiment will be described. First, a jig is used to fix the circuit pattern 4a and the wiring pattern 1a at a position where they mesh. Next, industrial pure water is poured into the internal space 4c from the terminal electrode tip opening 4b. The pressure of this industrial pure water is adjusted to, for example, 0.6 MPa to 0.8 MPa by passing it through a pressure regulator.

[0021] The internal space 4c, into which the industrial pure water is poured, expands because it has no exhaust port. This expansion causes the tip of the terminal electrode 4 to plastically deform, causing a change in the pitch of the uneven shape of the bellows shape of the circuit pattern 4a. As a result, the clearance with the wiring pattern 1a is filled, and the terminal electrode 4 is grounded in a self-supporting state.

[0022] Third embodiment 5 is a plan view showing a state before bonding of a joint structure according to embodiment 3 of the present disclosure. In embodiment 3, the shape of the fitting between terminal electrode 4 and insulating substrate 1 is different from the other embodiments.

[0023] The joint structure according to the third embodiment includes a concave wiring pattern 1c on the surface layer of an insulating substrate 1. The joint structure according to the third embodiment also includes a terminal electrode 4. The terminal electrode 4 has a terminal electrode tip 4d that meshes with the inside of the wiring pattern 1c. The terminal electrode 4 also has a terminal electrode tip opening 4e, and is shaped to have a bag-shaped internal space 4f extending inward from the terminal electrode tip opening 4e.

[0024] A method for joining the terminal electrode 4 and the insulating substrate 1 according to the third embodiment will be described. First, a jig is used to fix the terminal electrode tip 4d and the wiring pattern 1c at a position where they mesh. Next, compressed air is injected into the internal space 4f from the terminal electrode tip opening 4e. The pressure of this compressed air is adjusted to, for example, 0.6 MPa to 0.8 MPa by passing through a pressure regulator.

[0025] The internal space 4f into which the compressed air is injected expands because the internal space 4f does not have an exhaust port. As the air expands, the terminal electrode tip 4d undergoes plastic deformation, filling the clearance with the wiring pattern 1c. As a result, the terminal electrode 4 is grounded in a self-supporting state.

[0026] 6 is a cross-sectional view showing a state after joining of the joining structure according to the third embodiment of the present disclosure. As described above, in the third embodiment, compressed air is injected from the terminal electrode tip opening 4e to expand the terminal electrode tip 4d. As a result, the clearance between the terminal electrode tip 4d and the wiring pattern 1c is filled as shown in FIG. 6, so that the terminal electrode 4 is grounded in a self-supporting state. [Explanation of symbols]

[0027] 1. Insulating substrate 1a Wiring pattern 1c Wiring pattern 4 terminal electrode 4a Circuit Pattern 4b Terminal electrode tip opening 4c interior space 4d terminal electrode tip 4e Terminal electrode tip opening 4f interior space

Claims

1. An insulating substrate having a wiring pattern on its surface; A terminal electrode having a bag-shaped internal space with an opening at a tip end of the terminal electrode, The terminal electrode is grounded in a self-supporting state by being fitted with the wiring pattern. Semiconductor device.

2. The wiring pattern has a convex shape, the terminal electrode has a circuit pattern having a bellows shape, The circuit pattern is grounded in a self-supporting state by being fitted with the wiring pattern. The semiconductor device according to claim 1 .

3. The wiring pattern has a concave shape, The terminal electrode is grounded in a self-supporting state by being fitted with the wiring pattern. The semiconductor device according to claim 1 .

4. An insulating substrate having a wiring pattern on its surface; The terminal electrode has a bag-shaped internal space with an opening at the tip of the terminal electrode. A method for manufacturing a semiconductor device, comprising: a fixing process for fixing the terminal electrodes at positions where the terminal electrodes engage with the wiring pattern; a plastic deformation process in which the terminal electrode is expanded until the terminal electrode is grounded in a self-supporting state by being fitted with the wiring pattern; A method for manufacturing a semiconductor device comprising the steps of:

5. The plastic deformation treatment is A process of injecting compressed air into the internal space from the opening at the tip of the terminal electrode.

5. The method for manufacturing a semiconductor device according to claim 4.

6. The plastic deformation treatment is A process of injecting pure water into the internal space from the tip opening of the terminal electrode.

5. The method for manufacturing a semiconductor device according to claim 4.

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