Copper surface welding spot organic protective film structure

Abstract

The utility model relates to the field of PCBs (Printed Circuit Boards), in particular to a copper surface welding spot organic protective film structure which can play a role in protecting the surface of a copper column and prevent the surface of the copper column from being in contact with air to be oxidized. Comprising a chip at the bottom, an aluminum film layer is arranged on the chip, a copper column is arranged on the upper side of the aluminum film layer, the periphery of the bottom of the copper column is connected with a passivation layer, an organic protective film is arranged on the outer surface of the copper column, and the organic protective film is an alkylarylimidazole protective film. And the organic protective film covers the top surface and the side peripheral surface of the copper column. And the outer surface of the copper column at the inner side of the organic protective film is also provided with an enhanced conductive layer. The device is easy to operate, convenient to use and suitable for various PCBs.

Description

TECHNICAL FIELD

[0001] The utility model relates to the field of PCB circuit board, concretely is a copper surface solder joint organic protection film structure. BACKGROUND

[0002] Copper pillar bump is a kind of micro bump technology commonly used in advanced packaging, mainly used to realize the three-dimensional laminated interconnection of chip.Copper pillar bump has high reliability, good conductivity and heat conduction performance by forming reliable electrical and mechanical connection between chip and substrate.

[0003] The copper surface solder joint of existing technology is the bump structure, as shown in Figure Figure 1 It includes the chip 1 of bottom, the chip 1 is equipped with aluminium film layer 2, the upside of aluminium film layer 2 is equipped with copper column 3, and the periphery of copper column 3 bottom is connected with passivation layer 4.The copper plating bump structure of this structure can meet the demand of circuit board.But the outer surface of copper pillar bump is usually exposed after preparation, and oxidation occurs easily by contacting with air.Therefore, the copper column needs to be protected before the next process to ensure the quality of welding. SUMMARY

[0004] In view of the deficiencies of prior art, the utility model provides a copper surface solder joint organic protection film structure, the protection film structure can protect the surface of copper column and avoid oxidation by contacting with air.

[0005] To achieve the above object, the utility model provides the following technical scheme: a copper surface solder joint organic protection film structure, including the chip of bottom, the chip is equipped with aluminium film layer, the upside of aluminium film layer is equipped with copper column, and the periphery of copper column bottom is connected with passivation layer, the outer surface of copper column is equipped with organic protection film, and the organic protection film is alkyl aryl imidazole protection film.

[0006] As preferred technical scheme, the organic protection film covers the top surface and side peripheral surface of copper column.

[0007] As preferred technical scheme, the outer surface of copper column in the inside of organic protection film is further equipped with enhanced conductive layer.

[0008] As preferred technical scheme, the enhanced conductive layer is ITO film.

[0009] As preferred technical scheme, the height of copper column is 60-70 microns.

[0010] As preferred technical scheme, the diameter of copper column is 30-50 microns.

[0011] As preferred technical scheme, the thickness of organic protection film is 300-400 nanometers.

[0012] As a preferred technical solution, the thickness of the enhanced conductive layer is 300-400 nanometers.

[0013] Compared with the prior art, this utility model provides an organic protective film structure for copper solder joints, which has the following beneficial effects:

[0014] 1. This utility model provides an organic protective film on the outer surface of the copper pillar. The organic protective film is an alkylaryl imidazole protective film. When in use, the organic protective film can effectively protect the outer surface of the copper pillar. Under the action of flux, the organic protective film can be dissolved to expose the new copper surface, which can then complete the welding process with the molten solder.

[0015] 2. In this invention, an enhanced conductive layer is provided on the outer surface of the copper pillar inside the organic protective film. The enhanced conductive layer is an ITO film. When in use, the ITO film can enhance the conductivity of the copper pillar and also enhance its strength. Attached Figure Description

[0016] The accompanying drawings, which are included to provide a further understanding of the present invention, form part of this application:

[0017] Figure 1 This is a schematic diagram of the front view structure of an existing copper pillar protrusion;

[0018] Figure 2 This is a schematic diagram of the main structure of this utility model.

[0019] The diagram shows: 1. Chip; 2. Aluminum thin film layer; 3. Copper pillar; 4. Passivation layer; 5. Organic protective film; 6. Reinforcing conductive layer. Detailed Implementation

[0020] The technical solutions of the present utility model will be clearly and completely described below with reference to the accompanying drawings of the embodiments. Obviously, the described embodiments are only some embodiments of the present utility model, and not all embodiments. Based on the embodiments of the present utility model, all other embodiments obtained by those of ordinary skill in the art without creative effort are within the protection scope of the present utility model. Example 1

[0021] like Figure 2 As shown, a copper solder joint organic protective film structure includes a bottom chip 1, an aluminum thin film layer 2 on the chip 1, a copper pillar 3 on the upper side of the aluminum thin film layer 2, a passivation layer 4 connected around the bottom of the copper pillar 3, and an organic protective film 5 on the outer surface of the copper pillar 3, the organic protective film 5 being an alkylaryl imidazole protective film.

[0022] An organic protective film 5 covers the top and side surfaces of the copper pillar 3.

[0023] The outer surface of the copper column 3 on the inner side of the organic protective film 5 is further provided with a reinforced conductive layer 6. The reinforced conductive layer 6 is an ITO film. The ITO film has good conductivity, visible light transmittance and mechanical hardness.

[0024] The height of the copper column 3 is 60-70 microns. In this embodiment, the height of the copper column 3 is 65 microns.

[0025] The diameter of the copper column 3 is 30-50 microns. In this embodiment, the diameter of the copper column 3 is 40 microns.

[0026] The thickness of the organic protective film 5 is 300-400 nanometers. In this embodiment, the thickness of the organic protective film 5 is 350 nanometers.

[0027] The thickness of the reinforced conductive layer 6 is 300-400 nanometers. In this embodiment, the thickness of the reinforced conductive layer 6 is 350 nanometers.

[0028] In use, the organic protective film 5 can effectively protect the outer surface of the copper column 3, and under the action of the flux, the organic protective film 5 can be dissolved to expose the new copper surface, and complete the welding process with the molten solder. The ITO film can enhance the conductivity of the copper column 3 and enhance the strength of the copper column 3.

[0029] The components used in the utility model are all general standard components or components known to those skilled in the art, and their structure and principle are well known to those skilled in the art.

[0030] It should be noted that in this paper, the terms "first", "second", "upper", "lower", "front", "back", "left", "right", "top", "bottom", "inner", "outer" and the like indicate the orientation or positional relationship shown in the drawings, and are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between the entities or operations. Moreover, the terms "include", "contain" or any other variant thereof are intended to cover non-exclusive inclusion, so that the process, method, article or equipment including a series of elements not only includes those elements, but also includes other elements not explicitly listed or inherent to such process, method, article or equipment.

[0031] The structure, proportion, size and the like shown in the drawings of the present specification are only used to cooperate with the content disclosed in the specification, so as to be understood and read by those skilled in the art, and are not used to limit the implementation conditions of the utility model. Any modification of structure, change of proportion relationship or adjustment of size, which does not affect the effects and purposes that can be achieved by the utility model, should still fall within the scope of the technical content disclosed by the utility model.

[0032] While the embodiments of the present application have been illustrated and described, it will be understood by those skilled in the art that various changes, modifications, substitutions and alterations can be made therein without departing from the spirit and scope of the application, which is defined by the appended claims and their equivalents.

Claims

1. A copper pad organic protection film structure, comprising a bottom chip, an aluminum film layer on the chip, a copper column on the top side of the aluminum film layer, and a passivation layer connected to the bottom of the copper column, characterized in that: The outer surface of the copper column is provided with an organic protective film, which is an alkyl aryl imidazole protective film.

2. The structure of the organic protective film of copper surface solder joint according to claim 1, characterized in that: The outer surface of the copper column is provided with an organic protective film, which is an alkyl aryl imidazole protective film.

3. The organic protective film structure of copper surface solder joint according to claim 1, characterized in that: The outer surface of the copper column is provided with an organic protective film, which is an alkyl aryl imidazole protective film.

4. The structure of the organic protective film of copper surface solder joint according to claim 3, characterized in that: The outer surface of the copper column is provided with an organic protective film, which is an alkyl aryl imidazole protective film.

5. The structure of the organic protective film of copper surface solder joint according to claim 1, characterized in that: The outer surface of the copper column is provided with an organic protective film, which is an alkyl aryl imidazole protective film.

6. The structure of the organic protective film of copper surface solder joint according to claim 1, characterized in that: The outer surface of the copper column is provided with an organic protective film, which is an alkyl aryl imidazole protective film.

7. The structure of the organic protective film of copper surface solder joint according to claim 1, characterized in that: The outer surface of the copper column is provided with an organic protective film, which is an alkyl aryl imidazole protective film.

8. The structure of the organic protective film of copper surface solder joint according to claim 3, characterized in that: The outer surface of the copper column is provided with an organic protective film, which is an alkyl aryl imidazole protective film. The outer surface of the copper column is provided with an organic protective film, which is an alkyl aryl imidazole protective film. The outer surface of the copper column is provided with an organic protective film, which is an alkyl aryl imidazole protective film. The outer surface of the copper column is provided with an organic protective film, which is an alkyl aryl imid

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