Unit circuit board of tantalum capacitor and jointed board of tantalum capacitor circuit board

Abstract

The utility model discloses a unit circuit board and a jointed board of a tantalum capacitor. The jointed board comprises a metal carrier board and a plurality of unit circuit boards. The unit circuit board comprises a substrate, a first electrode and a second electrode, the first electrode comprises a first bottom bonding pad and a tantalum wire bonding pad, and the second electrode comprises a second bottom bonding pad and a tantalum block bonding pad; the first bottom pad is arranged in a first pad hole of the substrate, and the second bottom pad is arranged in a second pad hole of the substrate; the bottom surface of the tantalum wire bonding pad is connected with the top surface of the first bottom bonding pad, and the top surface of the second bottom bonding pad is connected with the bottom surface of the tantalum block bonding pad. In the jointed board, the substrates of all the unit circuit boards are mutually connected together and are in an undivided state; the first bottom bonding pad and the second bottom bonding pad of the unit circuit board are electroplated on the top surface of the metal carrier plate in a peelable manner, and the release oil layer is located between the top surface of the metal carrier plate and the bottom surface of the unit circuit board substrate. When the unit circuit board of the tantalum capacitor is manufactured, drilling of a via hole and plating of the via hole are not needed, and the manufacturing process is simple.

Description

Technical Field

[0001] The utility model relates to tantalum capacitors, in particular to a unit circuit board of a tantalum capacitor and a panel of a tantalum capacitor circuit board. Background Art

[0002] Tantalum capacitors belong to a kind of electrolytic capacitors and use metallic tantalum as the dielectric. Tantalum capacitors have high energy density, high reliability, stable electrical performance, and a relatively wide operating temperature range, and are widely used in high-end industrial markets and military markets.

[0003] Limited by the application environment of tantalum capacitors, the tantalum capacitor circuit board as a carrier has higher requirements for reliability. Especially for the process of plugging holes in vias, the general ink hole plugging process of circuit boards will cause resin shrinkage problems, and its heat resistance, voltage resistance, and moisture resistance are relatively poor, which can no longer meet the market requirements.

[0004] The utility model with the patent number CN202222172114.7 discloses a structure of a tantalum capacitor circuit board, which includes a substrate body, on the surface of which there are arranged a tantalum wire welding area and a tantalum block welding area from left to right in sequence; the tantalum wire welding area includes a first copper layer pressed on the left side of the substrate body, a first via hole is opened inside the first copper layer, and the first via hole is filled with first electroplated copper; the tantalum block welding area includes a second copper layer pressed on the right side of the substrate body, a second via hole is opened inside the second copper layer, and the second via hole is filled with second electroplated copper.

[0005] When manufacturing the tantalum capacitor circuit board of this utility model, it is necessary to drill via holes and electroplate via holes, the process is complex, and the manufacturing cost is high. Summary of the Invention

[0006] The technical problem to be solved by the utility model is to provide a unit circuit board of a tantalum capacitor that does not require drilling via holes and electroplating via holes during manufacturing.

[0007] To solve the above technical problem, the technical solution adopted by the utility model is that a unit circuit board of a tantalum capacitor includes a substrate, a first electrode, and a second electrode. The substrate includes a through first pad hole and a through second pad hole. The first electrode includes a first bottom pad and a tantalum wire pad, and the second electrode includes a second bottom pad and a tantalum block pad; the first bottom pad is arranged in the first pad hole, and the second bottom pad is arranged in the second pad hole; the tantalum wire pad is arranged above the substrate, and the bottom surface of the tantalum wire pad is connected to the top surface of the first bottom pad; the tantalum block pad is arranged above the substrate, and the top surface of the second bottom pad is connected to the bottom surface of the tantalum block pad.

[0008] For the above-mentioned unit circuit board, the top surfaces of the first bottom pad and the second bottom pad are flush with the top surface of the substrate.

[0009] For the unit circuit board described above, the tantalum wire pad includes a top pad plating layer and an intermediate plating layer. The bottom surface of the intermediate plating layer is connected to the top surface of the first bottom pad, and the top pad plating layer is plated on the top surface of the intermediate plating layer.

[0010] For the unit circuit board described above, the intermediate plating layer includes a first electroplating layer and a first electroless copper layer. The first electroless copper layer is deposited on the top surface of the first bottom pad or on the top surfaces of the first bottom pad and the substrate. The first electroplating layer is plated on the top surface of the first electroless copper layer, and the top pad plating layer is plated on the top surface of the first electroplating layer. The tantalum block pad includes a second electroplating layer and a second electroless copper layer. The second electroless copper layer is deposited on the top surface of the second bottom pad and on the top surface of the substrate, and the second electroplating layer is plated on the top surface of the second electroless copper layer.

[0011] For the unit circuit board described above, the height of the top surface of the first electroless copper layer is the same as the height of the top surface of the second electroless copper layer; the height of the top surface of the first electroplating layer is the same as the height of the top surface of the second electroplating layer.

[0012] For the unit circuit board described above, the cross-sectional area of the tantalum block pad is larger than the cross-sectional area of the tantalum wire pad.

[0013] For the unit circuit board described above, the bottom surfaces of the first bottom pad and the second bottom pad are flush with the bottom surface of the substrate or protrude from the bottom surface of the substrate.

[0014] For the unit circuit board described above, the first pad hole and the second pad hole are respectively stepped holes that are smaller at the top and larger at the bottom, and the first bottom pad and the second bottom pad respectively include steps that are smaller at the top and larger at the bottom.

[0015] A panel of tantalum capacitor circuit boards includes a carrier board and multiple unit circuit boards of the above-mentioned tantalum capacitors. The multiple unit circuit boards of the tantalum capacitors are arranged in a matrix, and the substrates of all the tantalum capacitor unit circuit boards are connected together and in an undivided state. The carrier board includes a metal carrier board and a release oil layer. The bottom surfaces of the first bottom pad and the second bottom pad of the unit circuit board are peelably electroplated on the top surface of the metal carrier board, and the release oil layer is located between the top surface of the metal carrier board and the bottom surface of the substrate of the unit circuit board.

[0016] For the panel described above, the carrier board includes an insulating layer that covers the bottom surface of the metal carrier board.

[0017] When manufacturing the unit circuit board and the panel of the tantalum capacitor of the present utility model, it is not necessary to drill via holes and plate via holes, and it is not necessary to be equipped with drilling equipment, and the manufacturing process is simple. [Description of the Drawings]

[0018] The present utility model will be further described in detail below in conjunction with the drawings and specific embodiments.

[0019] Figure 1 It is the front view of the unit circuit board of the tantalum capacitor in Embodiment 1 of the present utility model.

[0020] Figure 2 It is a top view of the unit circuit board of the tantalum capacitor in Embodiment 1 of the present utility model.

[0021] Figure 3 It is Figure 2 the A-A cross-sectional view in

[0022] Figure 4 It is a top view of the tantalum capacitor circuit board panel in Embodiment 2 of the present utility model.

[0023] Figure 5 It is a partial cross-sectional view of the structure of the tantalum capacitor circuit board panel in Embodiment 2 of the present utility model.

[0024] Figure 6 It is a cross-sectional view of the unit circuit board of the tantalum capacitor in Embodiment 3 of the present utility model.

[0025] Figure 7 It is a cross-sectional view of the unit circuit board of the tantalum capacitor in Embodiment 4 of the present utility model. [Specific Embodiments]

[0026] The structure of the unit circuit board of the tantalum capacitor in Embodiment 1 of the present utility model is as Figures 1 to 3 shown, and it includes a substrate 10, a first electrode 20 and a second electrode 30. The substrate 10 includes a through first pad hole 11 and a through second pad hole 12. The first electrode 20 includes a first bottom pad 21 and a tantalum wire pad 20A, and the second electrode 30 includes a second bottom pad 31 and a tantalum block pad 30A. The first bottom pad 21 is arranged in the first pad hole 11, and the second bottom pad 31 is arranged in the second pad hole 12. The bottoms of the first bottom pad 21 and the second bottom pad 31 respectively protrude from the bottom surface of the substrate 10. The top surfaces of the first bottom pad 21 and the second bottom pad 31 are flush with the top surface of the substrate 10.

[0027] The tantalum wire pad 20A is arranged above the substrate 10, and the bottom surface of the tantalum wire pad 20A is connected to the top surface of the first bottom pad 21. The tantalum block pad 30A is arranged above the substrate 10, and the top surface of the second bottom pad 31 is connected to the bottom surface of the tantalum block pad 30A.

[0028] The tantalum wire pad 20A includes a top pad plating 22 and an intermediate plating 23. The bottom surface of the intermediate plating 23 is connected to the top surface of the first bottom pad 21, and the top pad plating 22 is plated on the top surface of the intermediate plating 23.

[0029] The intermediate plating layer 23 includes a first electroplated layer 231 and a first electroless copper layer 232. The first electroless copper layer 232 can be deposited on the top surface of the first bottom pad 21 or on the top surfaces of the first bottom pad 21 and the substrate 10. The first electroplated layer 231 is plated on the top surface of the first electroless copper layer 232, and the top pad plating layer 22 is plated on the top surface of the first electroplated layer 231. The cross-sectional area of the top pad plating layer 22 is equal to or smaller than the cross-sectional area of the intermediate plating layer 23.

[0030] The tantalum block pad 30A includes a second electroplated layer 32 and a second electroless copper layer 33. The second electroless copper layer 33 is deposited on the top surface of the second bottom pad 31 and on the top surface of the substrate 10. The second electroplated layer 32 is plated on the top surface of the second electroless copper layer 33.

[0031] The first electroless copper layer 232 and the second electroless copper layer 33 are formed simultaneously, and the height of the top surface of the first electroless copper layer 232 is the same as the height of the top surface of the second electroless copper layer 33. The first electroplated layer 231 and the second electroplated layer 31 are formed simultaneously, and the height of the top surface of the first electroplated layer 231 is the same as the height of the top surface of the second electroplated layer 31.

[0032] The cross-sectional area of the tantalum block pad 30A is larger than the cross-sectional area of the tantalum wire pad 20A.

[0033] The structure of the tantalum capacitor circuit board panel in Embodiment 2 of the present utility model is as Figure 4 and Figure 5 shown, and includes a carrier board 40 and a plurality of the above-mentioned tantalum capacitor unit circuit boards 100. The plurality of tantalum capacitor unit circuit boards are arranged in a matrix, and the substrates 10 of all the tantalum capacitor unit circuit boards 100 are connected together and in an undivided state. The carrier board 40 includes an insulating layer 43 and a release oil layer 42. The bottom surfaces of the first bottom pads 21 and the second bottom pads 31 of the unit circuit board 100 are peelably electroplated on the top surface of the stainless steel carrier board 41. The release oil layer 42 is located between the top surface of the stainless steel carrier board 41 and the bottom surface of the substrate 10 of the unit circuit board. The insulating layer 43 covers the bottom surface of the stainless steel carrier board 41.

[0034] The manufacturing process of the tantalum capacitor circuit board panel in Embodiment 2 of the present utility model is as follows:

[0035] 1) Green glue is pasted on the bottom surface of the stainless steel carrier board 41 to form the insulating layer 43, and a first photosensitive film is coated on the top surface of the stainless steel carrier board 41; the first photosensitive film is exposed and developed to form a hollowed-out pattern corresponding to the first bottom pads 21 and the second bottom pads 31 of all the unit circuit boards 100;

[0036] 2) Electroplate the stainless steel carrier board 41 in the hollowed-out pattern formed by the first photosensitive film to form the first bottom pads 21 and the second bottom pads 31 of all the unit circuit boards 100, and remove the film;

[0037] 3) Apply a release agent on the top surface of the stainless steel carrier board 41;

[0038] 4) Print resin on the top surface of the stainless - steel carrier plate 41, the top surface of the first bottom pad 21, and the top surface of the second bottom pad 31, and then grind the top surface of the resin dielectric layer to expose the top surfaces of the first bottom pad 21 and the second bottom pad 31; the ground resin dielectric layer is the substrate 10;

[0039] 5) Electroplate copper on the entire board including the top surface of the resin dielectric layer, the top surface of the first bottom pad 21, and the top surface of the second bottom pad 31 after the entire board is immersed in copper.

[0040] 6) Cover a second photosensitive film on the copper - plated layer; expose and develop the first photosensitive film to form a pattern corresponding to the intermediate plating layer 23 and the tantalum - block pads 30A of all unit circuit boards 100;

[0041] 7) Etch and strip the film to form the intermediate plating layer 23 and the tantalum - block pads 30A of all unit circuit boards 100;

[0042] 8) Cover a third photosensitive film on the substrate 10, the intermediate plating layer 23, and the tantalum - block pads 30A; expose and develop the third photosensitive film to form a hollow pattern corresponding to the top - pad plating layer 22 of all unit circuit boards 100;

[0043] 9) Electroplate in the hollow pattern to form the top - pad plating layer 22 of all unit circuit boards 100;

[0044] 10) Strip the film to form the tantalum - capacitor circuit - board panel of the second embodiment of the present utility model.

[0045] The tantalum - capacitor circuit - board panel of the second embodiment of the present utility model is used for tantalum - capacitor packaging, and after the tantalum - capacitor is packaged, the substrate 10 is then cut.

[0046] The structure of the unit circuit board of the tantalum capacitor in the third embodiment of the present utility model is as Figure 6 shown in FIG. 3. The difference from the first embodiment is only that the first pad hole 11 and the second pad hole 12 are respectively stepped holes with a smaller upper part and a larger lower part, and the first bottom pad 21 and the second bottom pad 31 respectively include steps with a smaller upper part and a larger lower part. The cross - section of the tantalum - wire pad 20A is larger than the cross - section above the step of the first bottom pad 21.

[0047] The structure of the unit circuit board of the tantalum capacitor in the fourth embodiment of the present utility model is as Figure 7 shown. The difference between the fourth embodiment and the first embodiment is only that the cross - section of the tantalum - wire pad 20A is larger than the cross - section of the first bottom pad 21.

[0048] For the unit circuit boards and panels of the tantalum capacitors in the above - mentioned embodiments of the present utility model, when manufacturing, there is no need to drill via - holes and electroplate via - holes, and no drilling equipment is required; the unit circuit boards of the tantalum capacitors have a large over - current capacity, a thin thickness, and a simple manufacturing process.

Claims

1. A unit circuit board of a tantalum capacitor, comprising a substrate, a first electrode and a second electrode, characterized in that: The substrate includes a transparent first pad hole and a transparent second pad hole, the first electrode includes a first bottom pad and a tantalum wire pad, and the second electrode includes a second bottom pad and a tantalum block pad; the first bottom pad is arranged in the first pad hole, and the second bottom pad is arranged in the second pad hole; the tantalum wire pad is arranged above the substrate, and the bottom surface of the tantalum wire pad is connected to the top surface of the first bottom pad; the tantalum block pad is arranged above the substrate, and the top surface of the second bottom pad is connected to the bottom surface of the tantalum block pad.

2. The unit circuit board according to claim 1, characterized in that: A top surface of the first bottom pad and a top surface of the second bottom pad are flush with a top surface of the substrate.

3. The unit circuit board according to claim 2, characterized in that: The tantalum wire pad comprises a top pad plating layer and an intermediate plating layer, the bottom surface of the intermediate plating layer is connected to the top surface of the first bottom pad, and the top pad plating layer is plated on the top surface of the intermediate plating layer.

4. The unit circuit board according to claim 3, characterized in that: The middle plating layer includes a first electroplating layer and a first copper layer, the first copper layer is deposited on the top surface of the first bottom pad or on the top surface of the first bottom pad and the top surface of the substrate, the first electroplating layer is plated on the top surface of the first copper layer, and the top pad plating layer is plated on the top surface of the first electroplating layer; the tantalum block pad includes a second electroplating layer and a second copper layer, the second copper layer is deposited on the top surface of the second bottom pad and the top surface of the substrate, and the second electroplating layer is plated on the top surface of the second copper layer.

5. The unit circuit board according to claim 4, characterized in that: The height of the top surface of the first copper deposition layer is the same as the height of the top surface of the second copper deposition layer; the height of the top surface of the first electroplating layer is the same as the height of the top surface of the second electroplating layer.

6. The unit circuit board according to claim 1, characterized in that: The cross-sectional area of ​​the tantalum block pad is greater than the cross-sectional area of ​​the tantalum wire pad.

7. The unit circuit board according to claim 1, characterized in that: The bottom surface of the first bottom pad and the bottom surface of the second bottom pad are flush with the bottom surface of the substrate or protrude from the bottom surface of the substrate.

8. The unit circuit board according to claim 1, characterized in that: The first pad hole and the second pad hole are stepped holes which are smaller at the top and larger at the bottom, respectively. The first bottom pad and the second bottom pad include steps which are smaller at the top and larger at the bottom, respectively.

9. A tantalum capacitor circuit board assembly, comprising a carrier board, characterized in that: A unit circuit board comprising a plurality of tantalum capacitors as claimed in claim 1, wherein the unit circuit boards of the plurality of tantalum capacitors are arranged in a matrix, and the substrates of all the tantalum capacitor unit circuit boards are interconnected and in an undivided state; the carrier comprises a metal carrier and a release oil layer, the bottom surface of the first bottom pad and the bottom surface of the second bottom pad of the unit circuit board are releasably electroplated on the top surface of the metal carrier, and the release oil layer is located between the top surface of the metal carrier and the bottom surface of the unit circuit board substrate.

10. The panel according to claim 9, characterized in that: The carrier includes an insulating layer, which covers the bottom surface of the metal carrier.

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