Electronic component manufacturing process

Abstract

The present invention relates to a manufacturing process of electronic components. Copper pad slots and clamping copper posts are fabricated on a ceramic substrate through an etching process, and a silicon chip is soldered on a flexible substrate. There are more than 3 clamping holes arranged in the thickness direction of the flexible substrate, and more than 3 clamping copper posts are arranged on the ceramic substrate. The diameter of the clamping copper post is 95% - 99% of the aperture of the clamping hole. The clamping copper post is assembled with the clamping hole. The heat dissipation copper pad is located in the copper pad slot, and a gap of 3 - 20 μm is provided between the peripheral side and the bottom of the heat dissipation copper pad and the copper pad slot. Through a copper plating process, the gap between the peripheral side and the bottom of the heat dissipation copper pad and the copper pad slot is filled, and at the same time, the gap between the clamping copper post and the clamping hole is filled, so as to realize the assembly of the flexible substrate and the ceramic substrate. The flexible substrate acts as an intermediary, and the electroplating copper process is used to realize the integrated connection between the chip and the heat dissipation copper pad slot of the ceramic substrate, which can greatly improve the heat dissipation efficiency.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic components, and particularly to a manufacturing process for electronic components. Background Art

[0002] Electronic components have permeated all aspects of our lives.

[0003] A ceramic substrate refers to a special process board in which copper foil is directly bonded to the surface (single-sided or double-sided) of an alumina (Al 2 O 3 ) or aluminum nitride (AlN) ceramic substrate. The thickness of its copper layer can reach more than 2 mm. The manufactured composite substrate has excellent electrical insulation performance, high thermal conductivity, excellent soldering property, and high adhesion strength, and can be etched into various patterns like a PCB board, with a large current-carrying capacity. Therefore, ceramic substrates have become the basic materials for high-power power electronic circuit structure technology and interconnection technology.

[0004] In the encapsulation of a chip and a ceramic substrate in the prior art, the heat dissipation of the chip is an important issue to be solved. Summary of the Invention

[0005] The technical problem to be solved by the present invention is to provide a manufacturing process for electronic components and an electronic component based on a thick copper ceramic substrate manufactured by the process, with high heat dissipation efficiency.

[0006] A manufacturing process for an electronic component includes:

[0007] A. Manufacturing copper pad slots and clamping copper posts on a ceramic substrate through an etching process, and soldering a silicon chip on a flexible substrate;

[0008] There are more than 3 clamping holes provided in the thickness direction of the flexible substrate, and more than 3 clamping copper posts are provided on the ceramic substrate. The diameter of the clamping copper post is 95% - 99% of the aperture of the clamping hole. The clamping copper post is assembled with the clamping hole. The heat dissipation copper pad is located in the copper pad slot, and a gap of 3 - 20 μm is provided between the peripheral side and the bottom of the heat dissipation copper pad and the copper pad slot;

[0009] B. Filling the gap between the peripheral side and the bottom of the heat dissipation copper pad and the copper pad slot through a copper plating process, and simultaneously filling the gap between the clamping copper post and the clamping hole.

[0010] In this embodiment, the copper plating process includes electroless copper plating and electroplating copper.

[0011] In this embodiment, the thickness of the copper layer of the electroless copper plating is 1 - 5 μm;

[0012] During electroplating copper, it is a double-loop electroplating process, and electroplating clip clamping points are simultaneously provided on the ceramic substrate and the flexible substrate;

[0013] When the gap between the heat dissipation copper pad and the copper pad slot is 4 - 20 μm, double-loop electroplating process is used for electroplating, and at the same time, electroplating is carried out through the clamping points of the electroplating clips on the ceramic substrate and the flexible substrate; when the gap between the heat dissipation copper pad and the copper pad slot is less than 4 μm, single-loop electroplating process is used, and electroplating is only carried out through the clamping points of the electroplating clips on the ceramic substrate or the flexible substrate.

[0014] Preferably, the number of silicon chips is more than 2, the flexible substrate is provided with more than two heat dissipation copper pads, the heat dissipation copper pads are located at the bottom of the silicon chips, and the ceramic substrate is provided with more than 2 copper pad slots;

[0015] The two copper pad slots have different bottom heights, the flexible substrate is bent, and at least 2 heat dissipation copper pads are located in the copper pad slots at different heights.

[0016] An electronic component based on a thick copper ceramic substrate includes a silicon chip, a ceramic substrate and a flexible substrate;

[0017] The silicon chip is a chip with double-sided pads, and the bottom surface of the silicon chip is welded on the flexible substrate;

[0018] The flexible substrate is provided with heat dissipation copper pads, the heat dissipation copper pads are located on one side or the bottom of the silicon chip, and the ceramic substrate is provided with copper pad slots;

[0019] More than 3 clamping holes are provided in the thickness direction of the flexible substrate, more than 3 clamping copper columns are provided on the ceramic substrate, the diameter of the clamping copper columns is 95% - 99% of the aperture of the clamping holes. After the clamping copper columns and the clamping holes are assembled, the heat dissipation copper pads are located in the copper pad slots, and a gap of 3 - 20 μm is provided between the peripheral side and the bottom of the heat dissipation copper pads and the copper pad slots;

[0020] Through the copper plating process, the gap between the clamping copper columns and the clamping holes is filled, and at the same time, the gap between the heat dissipation copper pads and the copper pad slots is filled to realize the assembly of the flexible substrate and the ceramic substrate.

[0021] Preferably, the peripheral side of the clamping hole is resin or a composition of resin and fiber.

[0022] Preferably, the clamping hole is a copper-plated hole with a copper layer; the clamping copper column is a copper clamping copper column.

[0023] Preferably, the ceramic substrate is a circuit board with copper layers on both sides, the ceramic substrate is provided with a first circuit pattern, and the copper clamping copper column is a part of the first circuit pattern;

[0024] The flexible substrate includes at least two or more second circuit patterns, and the copper-plated hole is a part of the second circuit pattern;

[0025] After the copper-plated hole and the copper snap-in copper post are assembled through the copper plating process, the first circuit pattern and the second circuit pattern are assembled.

[0026] Preferably, the copper snap-in copper post is higher than other parts of the first circuit pattern; the copper snap-in copper post and other parts of the first circuit pattern are made of the same copper layer of the ceramic substrate through different etching processes.

[0027] Preferably, the insulating layer of the flexible substrate is composed of one or two of polyimide, BT resin or epoxy resin.

[0028] BT resin is a thermosetting resin with bismaleimide (BMI) and triazine as the main resin components, and adding epoxy resin, polyphenylene ether resin (PPE) or allyl compound as a modification component, which is called BT resin.

[0029] Preferably, the insulating layer of the ceramic substrate is aluminum oxide or aluminum nitride.

[0030] Preferably, a thermoelectric conversion layer is provided on the bottom wall of the copper pad card slot, and the thermoelectric conversion layer is firmly connected to the bottom wall of the heat dissipation copper pad through a copper plating layer.

[0031] Preferably, the copper plating process includes electroless copper plating and electroplating copper.

[0032] Preferably, the thickness of the copper layer of electroless copper plating is 1-5μm;

[0033] When electroplating copper, it is a double-loop electroplating process, and electroplating clips clamping points are simultaneously provided on the ceramic substrate and the flexible substrate;

[0034] When the gap between the heat dissipation copper pad and the copper pad card slot is 4-20μm, electroplating is carried out by the double-loop electroplating process, and electroplating is carried out through the electroplating clips clamping points on the ceramic substrate and the flexible substrate at the same time; when the gap between the heat dissipation copper pad and the copper pad card slot is less than 4μm, a single-loop electroplating process is adopted, and electroplating is carried out only through the electroplating clips clamping points on the ceramic substrate or the flexible substrate.

[0035] Preferably, the number of silicon chips is more than 2, the flexible substrate is provided with more than two heat dissipation copper pads, the heat dissipation copper pads are located at the bottom of the silicon chips, and the ceramic substrate is provided with more than 2 copper pad card slots;

[0036] The two copper pad card slots have different bottom heights, the flexible substrate is bent, and at least 2 heat dissipation copper pads are located in the copper pad card slots at different heights.

[0037] The beneficial effects of the present invention are as follows: The present invention relates to a manufacturing process of electronic components. Copper pad slots and clamping copper posts are fabricated on a ceramic substrate through an etching process, and a silicon chip is soldered on a flexible substrate. There are more than 3 clamping holes provided in the thickness direction of the flexible substrate, and more than 3 clamping copper posts are provided on the ceramic substrate. The diameter of the clamping copper posts is 95% - 99% of the aperture of the clamping holes. The clamping copper posts are assembled with the clamping holes. The heat dissipation copper pad is located within the copper pad slot, and there is a gap of 3 - 20 μm between the peripheral side and the bottom of the heat dissipation copper pad and the copper pad slot. Through a copper plating process, the gap between the peripheral side and the bottom of the heat dissipation copper pad and the copper pad slot is filled, and at the same time, the gap between the clamping copper posts and the clamping holes is filled, realizing the assembly of the flexible substrate and the ceramic substrate. The flexible substrate acts as an intermediary, and by using an electroplated copper process, an integrated connection between the chip and the heat dissipation copper pad slot of the ceramic substrate is achieved, which can greatly improve the heat dissipation efficiency.

[0038] The present invention also relates to an electronic component based on a thick copper ceramic substrate, including a silicon chip, a ceramic substrate, and a flexible substrate. The silicon chip is a chip with double-sided pads, and the bottom surface of the silicon chip is soldered on the flexible substrate. The flexible substrate is provided with a heat dissipation copper pad, and the heat dissipation copper pad is located on one side or at the bottom of the silicon chip. The ceramic substrate is provided with a copper pad slot. There are more than 3 clamping holes provided in the thickness direction of the flexible substrate, and more than 3 clamping copper posts are provided on the ceramic substrate. The diameter of the clamping copper posts is 95% - 99% of the aperture of the clamping holes. After the clamping copper posts are assembled with the clamping holes, the heat dissipation copper pad is located within the copper pad slot, and there is a gap of 3 - 20 μm between the peripheral side and the bottom of the heat dissipation copper pad and the copper pad slot. Through a copper plating process, the gap between the clamping copper posts and the clamping holes is filled, and at the same time, the gap between the heat dissipation copper pad and the copper pad slot is filled, realizing the assembly of the flexible substrate and the ceramic substrate. The flexible substrate acts as an intermediary, and the flexible substrate can be made very thin and is made of high heat dissipation materials such as BT. By using an electroplated copper process, an integrated connection between the heat dissipation copper pad at the bottom of the chip and the heat dissipation copper pad slot of the ceramic substrate is achieved. The heat dissipation copper pad slot and the large-area copper block on its peripheral side are integrally and tightly combined through a copper plating process, which can greatly improve the heat dissipation efficiency. Description of the Drawings

[0039] The following further describes the electronic component based on the thick copper ceramic substrate of the present invention with reference to the drawings.

[0040] Figure 1 It is a process flow diagram of a manufacturing process of an electronic component of the present invention.

[0041] Figure 2 It is an exploded view of the first perspective of an electronic component based on a thick copper ceramic substrate of the present invention.

[0042] Figure 3 It is an exploded view of the second perspective of an electronic component based on a thick copper ceramic substrate of the present invention.

[0043] Figure 4 This is an exploded view of an electronic component based on a thick copper ceramic substrate according to the present invention from a third perspective.

[0044] Figure 5 This is an exploded view of another embodiment of an electronic component based on a thick copper ceramic substrate according to the present invention.

[0045] In the figure:

[0046] 1 - silicon chip; 2 - ceramic substrate; 3 - flexible substrate; 31 - heat dissipation copper pad; 32 - clamping hole; 21 - copper pad card slot; 22 - clamping copper column; 4 - thermoelectric conversion layer; 5 - large - area heat dissipation copper layer. Detailed implementation manners

[0047] Next, in combination with the attached Figures 1 to 5 The manufacturing process of an electronic component of the present invention and the corresponding electronic component based on a thick copper ceramic substrate will be further described.

[0048] First, the manufacturing process of this electronic component will be introduced.

[0049] A manufacturing process of an electronic component includes:

[0050] A. On the ceramic substrate 2, the copper pad card slot 21 and the clamping copper column 22 are made by an etching process, and the silicon chip 1 is welded on the flexible substrate 3;

[0051] In the thickness direction of the flexible substrate 3, there are more than 3 clamping holes 32, and on the ceramic substrate 2, there are more than 3 clamping copper columns 22. The diameter of the clamping copper column 22 is 95% - 99% of the aperture of the clamping hole 32. The clamping copper column 22 is assembled with the clamping hole 32. The heat dissipation copper pad 31 is located in the copper pad card slot 21, and there is a gap of 3 - 20 μm between the circumferential side and the bottom of the heat dissipation copper pad 31 and the copper pad card slot 21;

[0052] B. Through a copper plating process, the gap between the circumferential side and the bottom of the heat dissipation copper pad 31 and the copper pad card slot 21 is filled, and at the same time, the gap between the clamping copper column 22 and the clamping hole 32 is filled.

[0053] In this embodiment, the copper plating process includes electroless copper plating and electroplating copper.

[0054] In this embodiment, the thickness of the copper layer of the electroless copper plating is 1 - 5 μm;

[0055] When electroplating copper, it is a double - loop electroplating process, and electroplating clip clamping points are simultaneously provided on the ceramic substrate 2 and the flexible substrate 3;

[0056] When the gap between the heat dissipation copper pad 31 and the copper pad slot 21 is 4 - 20 μm, electroplating is carried out using a double-loop electroplating process, and at the same time, electroplating is carried out through the electroplating clip clamping points on the ceramic substrate 2 and the flexible substrate 3; when the gap between the heat dissipation copper pad 31 and the copper pad slot 21 is less than 4 μm, a single-loop electroplating process is adopted, and electroplating is carried out only through the electroplating clip clamping points on the ceramic substrate 2 or the flexible substrate 3.

[0057] In this embodiment, the number of silicon chips 1 is more than 2, the flexible substrate 3 is provided with more than two heat dissipation copper pads 31, the heat dissipation copper pads 31 are located at the bottom of the silicon chips 1, and the ceramic substrate 2 is provided with more than 2 copper pad slots 21;

[0058] The two copper pad slots 21 have different bottom heights, the flexible substrate 3 is bent, and at least 2 heat dissipation copper pads 31 are located in the copper pad slots 21 at different heights.

[0059] Then, an electronic component manufactured based on the above manufacturing process is introduced.

[0060] An electronic component based on a thick copper ceramic substrate includes a silicon chip 1, a ceramic substrate 2, and a flexible substrate 3;

[0061] The silicon chip 1 is a chip with double-sided pads, and the bottom surface of the silicon chip 1 is welded to the flexible substrate 3;

[0062] The flexible substrate 3 is provided with heat dissipation copper pads 31, the heat dissipation copper pads 31 are located on one side or the bottom of the silicon chip 1, and the ceramic substrate 2 is provided with copper pad slots 21;

[0063] In the thickness direction of the flexible substrate 3, there are more than 3 clamping holes 32, and on the ceramic substrate 2, there are more than 3 clamping copper posts 22. The diameter of the clamping copper posts 22 is 95% - 99% of the aperture of the clamping holes 32. After the clamping copper posts 22 and the clamping holes 32 are assembled, the heat dissipation copper pads 31 are located in the copper pad slots 21, and a gap of 3 - 20 μm is provided between the circumferential side and the bottom of the heat dissipation copper pads 31 and the copper pad slots 21;

[0064] Through the copper plating process, the gap between the clamping copper posts 22 and the clamping holes 32 is filled, and at the same time, the gap between the heat dissipation copper pads 31 and the copper pad slots 21 is filled to realize the assembly of the flexible substrate 3 and the ceramic substrate 2.

[0065] In this embodiment, the circumferential side of the copper pad slot 21 is a large-area heat dissipation copper area 5. After copper plating, the heat dissipation copper pads 31 are integrally connected to the copper pad slots 21 and the large-area heat dissipation copper area.

[0066] The flexible substrate acts as an intermediary. The flexible substrate can be made very thin and is made of high heat dissipation materials such as BT. The electroplating copper process is used to integrally connect the heat dissipation copper pad at the bottom of the chip and the heat dissipation copper pad slot of the ceramic substrate. The heat dissipation copper pad slot and the large-area copper block on its periphery are integrally and tightly combined through the copper plating process, which can greatly improve the heat dissipation efficiency.

[0067] In this embodiment, the periphery of the clamping hole 32 is resin or a composition of resin and fiber.

[0068] In this embodiment, the clamping hole 32 is a copper-plated hole provided with a copper layer; the clamping copper column 22 is a copper clamping copper column.

[0069] In this embodiment, the number of silicon chips 1 is more than 2. The flexible substrate 3 is provided with more than two heat dissipation copper pads 31. The heat dissipation copper pads 31 are located at the bottom of the silicon chips 1. The ceramic substrate 2 is provided with more than 2 copper pad slots 21;

[0070] The two copper pad slots 21 have different bottom heights. The flexible substrate 3 is bent, and at least 2 heat dissipation copper pads 31 are located in the copper pad slots 21 at different heights.

[0071] In this embodiment, the ceramic substrate 2 is a circuit board with copper layers on both sides. The ceramic substrate 2 is provided with a first circuit pattern, and the copper clamping copper column is a part of the first circuit pattern;

[0072] The flexible substrate 3 includes at least two or more second circuit patterns, and the copper-plated hole is a part of the second circuit pattern;

[0073] After the copper-plated hole and the copper clamping copper column are assembled through the copper plating process, the first circuit pattern and the second circuit pattern are assembled.

[0074] In this embodiment, the copper clamping copper column is higher than other parts of the first circuit pattern; the copper clamping copper column and other parts of the first circuit pattern are made of the same copper layer of the ceramic substrate through different etching processes.

[0075] In this embodiment, the insulating layer of the flexible substrate 3 is composed of one or two of polyimide, BT resin or epoxy resin.

[0076] BT resin is a thermosetting resin with bismaleimide (BMI) and triazine as the main resin components, and epoxy resin, polyphenylene ether resin (PPE) or allyl compound, etc. are added as modified components, and is called BT resin.

[0077] In this embodiment, the insulating layer of the ceramic substrate 2 is aluminum trioxide or aluminum nitride.

[0078] The ceramic substrate refers to the copper foil directly bonded to alumina (Al 2 O3 ) or a special process board on the surface (single-sided or double-sided) of an aluminum nitride (AlN) ceramic substrate. The manufactured ultra-thin composite substrate has excellent electrical insulation performance, high thermal conductivity, excellent solderability, and high adhesion strength, and can be etched into various patterns like a PCB board, with a large current-carrying capacity. Therefore, the ceramic substrate has become the basic material for high-power power electronic circuit structure technology and interconnection technology.

[0079] In this embodiment, a thermoelectric conversion layer 4 is provided on the bottom wall of the copper pad slot 21, and the thermoelectric conversion layer 4 is firmly connected to the bottom wall of the heat dissipation copper pad 31 through a copper plating layer.

[0080] In this embodiment, the copper plating process includes electroless copper plating and electroplating copper.

[0081] In this embodiment, the thickness of the copper layer of the electroless copper plating is 1 - 5 μm;

[0082] During electroplating copper, it is a double-loop electroplating process, and electroplating clips clamping points are simultaneously provided on the ceramic substrate 2 and the flexible substrate 3;

[0083] When the gap between the heat dissipation copper pad 31 and the copper pad slot 21 is 4 - 20 μm, electroplating is carried out using the double-loop electroplating process, and electroplating is simultaneously carried out through the electroplating clips clamping points on the ceramic substrate 2 and the flexible substrate 3; when the gap between the heat dissipation copper pad 31 and the copper pad slot 21 is less than 4 μm, a single-loop electroplating process is adopted, and electroplating is carried out only through the electroplating clips clamping points on the ceramic substrate 2 or the flexible substrate 3.

[0084] The present invention is not limited to the above embodiments. The technical solutions of the above various embodiments of the present invention can be cross-combined with each other to form new technical solutions. In addition, all technical solutions formed by equivalent substitution fall within the protection scope required by the present invention.

Claims

1. A manufacturing process for an electronic component, characterized in that, it includes: A. Copper pad slots (21) and clamping copper posts (22) are fabricated on a ceramic substrate (2) through an etching process. A silicon chip (1) is soldered on a flexible substrate (3), and the flexible substrate (3) is provided with heat dissipation copper pads (31); More than 3 clamping holes (32) are provided in the thickness direction of the flexible substrate (3). More than 3 clamping copper posts (22) are provided on the ceramic substrate (2). The diameter of the clamping copper post (22) is 95% - 99% of the aperture of the clamping hole (32). The clamping copper post (22) is assembled with the clamping hole (32). The heat dissipation copper pad (31) is located within the copper pad slot (21), and a gap of 3 - 20 μm is provided between the circumferential side and the bottom of the heat dissipation copper pad (31) and the copper pad slot (21); B. Through a copper plating process, the gap between the circumferential side and the bottom of the heat dissipation copper pad (31) and the copper pad slot (21) is filled, and at the same time, the gap between the clamping copper post (22) and the clamping hole (32) is filled.

2. The manufacturing process for an electronic component according to claim 1, characterized in that, the number of the silicon chips (1) is more than 2. The flexible substrate (3) is provided with more than two heat dissipation copper pads (31). The heat dissipation copper pads (31) are located at the bottom of the silicon chips (1). The ceramic substrate (2) is provided with more than 2 copper pad slots (21); The two copper pad slots (21) have different bottom heights. The flexible substrate (3) is bent, and at least 2 of the heat dissipation copper pads (31) are located in the copper pad slots (21) at different heights.

3. The manufacturing process for an electronic component according to claim 2, characterized in that, the copper plating process includes electroless copper plating and electroplating copper; the thickness of the copper layer of the electroless copper plating is 1 - 5 μm; During electroplating copper, it is a double - circuit electroplating process. Electroplating clip clamping points are simultaneously provided on the ceramic substrate (2) and the flexible substrate (3); When the gap between the heat dissipation copper pad (31) and the copper pad slot (21) is 4 - 20 μm, electroplating is carried out using the double - circuit electroplating process, and at the same time, electroplating is carried out through the electroplating clip clamping points on the ceramic substrate (2) and the flexible substrate (3). When the gap between the heat dissipation copper pad (31) and the copper pad slot (21) is less than 4 μm, a single - circuit electroplating process is adopted, and electroplating is carried out only through the electroplating clip clamping points on the ceramic substrate (2) or the flexible substrate (3).

4. The manufacturing process for an electronic component according to claim 3, characterized in that, the clamping hole (32) is provided with a copper - plated hole with a copper layer; the clamping copper post (22) is a copper clamping copper post; The circumferential side of the clamping hole (32) is resin or a composition of resin and fiber.

5. The manufacturing process for an electronic component according to claim 4, characterized in that, the ceramic substrate (2) is a circuit board with copper layers on both sides. The ceramic substrate (2) is provided with a first circuit pattern, and the copper clamping copper post is a part of the first circuit pattern; The flexible substrate (3) includes at least two or more second circuit patterns, and the copper-plated hole is a part of the second circuit pattern; After the copper-plated hole and the copper clamping copper post are assembled by the copper-plating process, the first circuit pattern and the second circuit pattern are assembled.

6. The manufacturing process of the electronic component according to claim 5, characterized in that, the copper clamping copper post is higher than other parts of the first circuit pattern; the copper clamping copper post and other parts of the first circuit pattern are made of the same copper layer of the ceramic substrate through different etching processes.

7. The manufacturing process of the electronic component according to claim 6, characterized in that, the insulating layer of the flexible substrate (3) is composed of one or two of polyimide, BT resin or epoxy resin; the insulating layer of the ceramic substrate (2) is aluminum trioxide or aluminum nitride.

8. The manufacturing process of the electronic component according to claim 7, characterized in that, a thermoelectric conversion layer (4) is provided on the bottom wall of the copper pad card slot (21), and the thermoelectric conversion layer (4) is fixedly connected to the bottom wall of the heat dissipation copper pad (31) through a copper plating layer.

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