Tank body circulating system, circuit board etching method and circuit board electrodeless / polar electroplating method

Abstract

The invention provides a tank body circulating system, circuit board etching and circuit board electrodeless / polar electroplating methods. The tank body circulating system comprises a tank body, a circulating pump and a fixing device, the tank body is provided with a partition plate, the partition plate divides the space in the tank body into an accommodating space and a temporary storage space, and the partition plate is lower than the tank wall of the temporary storage space; the containing space is provided with a liquid outlet, the temporary storage space is provided with a liquid inlet, the liquid outlet and the liquid inlet are both connected with the circulating pump, and liquid flows out from the liquid outlet and flows in from the liquid inlet; the fixing device is used for arranging a plate-shaped object in the accommodating space. The surface treatment method can improve the treatment effect when the material with the blind hole is subjected to surface treatment.

Description

Technical Field

[0001] The present invention relates to the technical field of surface treatment equipment, and particularly relates to a tank circulation system for processing materials with blind holes on the surface, a circuit board etching method, and a circuit board non-polar / polar electroplating method. Background Art

[0002] In order to enable surface treatment to be carried out efficiently, in the past, the material to be treated was immersed in the surface treatment liquid and the circulation of the surface treatment liquid was realized by a pump, so that the concentration of the treatment liquid on the surface of the material to be treated could be maintained stable, and stirring in the tank could further improve the efficiency of surface treatment. For example, when performing plating treatment, in addition to improving the plating efficiency, the above method can also make the coating thickness of the object to be plated more uniform.

[0003] The utility model patent with the invention creation name of "electroplating equipment" and the Taiwan, China patent publication number of "TWM627065U" discloses an electroplating equipment that adopts the above structure and is provided with a stirrer at the bottom of the electroplating tank.

[0004] The invention patent application with the invention creation name of "surface treatment device, surface treatment method and stirrer" and the Taiwan, China patent publication number of "TW201943897A" discloses a surface treatment device that adopts another method to achieve the stirring effect by reciprocating the object to be plated in the treatment tank.

[0005] The invention patent application with the invention creation name of "plating device and plating method" and the Taiwan, China patent publication number of "TW200936818A" discloses a plating device that circulates and injects the overflowed treatment liquid of the plating tank from the bottom of the tank and then mixes it with a stirrer.

[0006] The invention patent application with the invention creation name of "electroplating device and electroplating method" and the Taiwan, China patent publication number of "TW201109478A" discloses an electroplating device that, in addition to having a circulation system, uses the jet flow generated by a nozzle to stir the plating solution around the cathode.

[0007] However, when processing materials with blind holes, such as circuit boards with blind holes, the bubbles generated by stirring may instead stay in the blind holes, thereby hindering the interaction between the blind holes and the treatment liquid, resulting in the inability to achieve the same treatment effect as the general surface in the blind holes and reducing the product quality. Summary of the Invention

[0008] The purpose of the present invention is to provide a tank circulation system, a circuit board etching method, and a circuit board non-polar / polar electroplating method that do not use a stirrer to improve the treatment effect when performing surface treatment on materials with blind holes.

[0009] In a first aspect, the present invention provides a circulation system, comprising a tank body, a circulation pump and a fixing device; the tank body has a first partition board, which divides the tank body into a containing space and a first temporary storage space, and the height of the first partition board is lower than the tank wall of the first temporary storage space; the containing space has a first liquid outlet, the first temporary storage space has a first liquid inlet, and both the first liquid outlet and the first liquid inlet are connected to the circulation pump, and the liquid flows out from the first liquid outlet and flows into from the first liquid inlet; the fixing device is used to place a material to be processed in the containing space.

[0010] More preferably, the material to be processed is a plate-shaped object, and the plate-shaped object is arranged parallel to the first partition board.

[0011] More preferably, the first liquid outlet is arranged below the containing space and between the first partition board and the material to be processed.

[0012] In some preferred specific embodiments, the containing space further includes a second partition board, and the second partition board divides a second temporary storage space on the opposite side of the first temporary storage space; the height of the second partition board is lower than the tank wall of the second temporary storage space; the containing space has a second liquid outlet, the second temporary storage space has a second liquid inlet, and both the second liquid outlet and the second liquid inlet are connected to the circulation pump, and the liquid flows out from the second liquid outlet and flows into from the second liquid inlet.

[0013] More preferably, the material to be processed, the first partition board and the second partition board are arranged parallel to each other.

[0014] More preferably, the second liquid outlet is arranged below the containing space and between the second partition board and the material to be processed.

[0015] In another aspect, the present invention provides a circuit board etching method, which is implemented by using the tank body circulation system as described above, wherein the material to be processed is a circuit board to be plated; an etching solution is injected into the tank body.

[0016] In another aspect, the present invention provides a circuit board electroless plating method, which is implemented by using the tank body circulation system as described above, wherein the material to be processed is a circuit board to be plated; a plating solution is injected into the tank body.

[0017] In another aspect, the present invention provides a circuit board electroplating method with electrodes, which is implemented by using the tank body circulation system as described above, wherein the material to be processed is a circuit board to be plated; a plating solution is injected into the tank body.

[0018] Especially when the circuit board to be plated has at least one blind hole, the efficacy of the present invention can be more prominent.

[0019] Compared with the prior art, the technical solution described in the present invention has the following characteristics and advantages:

[0020] The tank circulation system described in the present invention can achieve rapid treatment of the material surface without a stirrer, and can improve the treatment effect when treating the surface of materials with blind holes. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] Figure 1 is a schematic structural diagram of a traditional circulation system;

[0022] Figures 2A to 2C is Figure 1 the blind hole plating result of the circulation system in Figure 2A is a micrograph of a blind hole; Figure 2B and Figure 2C are partial enlarged views of the micrograph;

[0023] Figure 3 is a schematic diagram of the first setting example of the tank circulation system described in the present invention;

[0024] Figures 4A to 4C is Figure 3 the blind hole plating result of the tank circulation system in Figure 4A is a micrograph of a blind hole, Figure 4B and Figure 4C are partial enlarged views of the micrograph;

[0025] Figures 5A to 5C is Figure 3 the blind hole plating result of another tank circulation system in Figure 5A is a micrograph of a blind hole, Figure 5B and Figure 5C are partial enlarged views of the micrograph;

[0026] Figure 6 is a schematic diagram of the second setting example of the tank circulation system described in the present invention;

[0027] Figures 7A to 7C is Figure 6 the blind hole plating result of the tank circulation system in Figure 7A is a micrograph of a blind hole, Figure 7B and Figure 7C are partial enlarged views of the micrograph.

[0028] Description of the reference numerals in the drawings:

[0029] 10. Tank; 20. Pump; 30. Fixing device; 40. Material to be treated; 50. Overflow tank; 60. Stirrer; 70. Bubble; 100. Accommodating space; 101. Liquid inlet; 102. Liquid outlet; 110. First partition; 111. First temporary storage space; 120. Second partition; 121. Second temporary storage space. Detailed Embodiments

[0030] The embodiments of the present invention are described below with the aid of the accompanying drawings, which are not intended to limit the scope of the patent application. All the technical features disclosed in this specification can be combined in any manner. Alternative solutions for the same, equivalent, or similar purposes can replace each technical feature disclosed in this specification. Therefore, unless otherwise specified, each disclosed technical feature is merely a series of general examples of equivalent or similar features.

[0031] The present invention includes a tank circulation system for surface treatment, as well as a method for circuit board etching and electroless / polarized electroplating of circuit boards, which can be used in manufacturing processes such as desmearing, etching, electrode electroplating, electroless plating, etc. To illustrate the better effects produced by the present invention compared with the prior art, this specification will take the coating thickness of the blind hole wall after plating treatment of a material to be processed with blind holes as an example to evaluate the effects of this device and method in improving the efficiency of blind hole treatment.

[0032] In this specification, the material to be processed will be exemplified by a substrate with blind holes, the blind hole diameter of which is about 100 μm, the hole depth is about 90 μm, and the aspect ratio is about 0.9.

[0033] In this specification, the plating treatment refers to the process of generating a metal coating on the surface of the substrate by electroless plating. The metal includes but is not limited to silver, gold, platinum, palladium, copper, cobalt, and nickel. Copper will be used as an example below.

[0034] In this specification, the coating thickness refers to the thickness of the metal coating formed on the blind hole wall near the bottom after the substrate has undergone plating treatment. The traditional circulation system has poor exchange efficiency for blind holes, especially for the hole wall closer to the bottom of the blind hole, where the efficiency is even worse. Therefore, in this specification, the coating thickness of the metal coating formed on the blind hole wall near the bottom is specifically used to evaluate the effects of the present invention.

[0035] The method for measuring the coating thickness is to prepare microsections and observe according to IPC-TM-650 manual 2.1.1D. The surface of the microsection is polished by an ion milling machine (HITACHI-Ion Milling System IM4000Plus), and then the coating thickness is measured by an electron microscope (HITACHI-FE-SEM SU5000).

[0036] The steps of the electroless plating process exemplified in this specification are summarized in the following table.

[0037]

[0038]

[0039]

[0040] When performing the electroless plating in step B10, a conventional circulation system or the tank circulation system provided by the present invention will be used, and the coating thicknesses will be measured and compared respectively to clarify the substantial progress of the present invention compared with the prior art.

[0041] Comparative example: Conventional circulation system

[0042] A conventional circulation system is as Figure 1 shown. A receiving space 100 is formed in the tank 10. During operation, a treatment liquid is injected into the receiving space 100, which is the electroless plating bath in step B10 in this example. When the liquid level of the treatment liquid in the receiving space is higher than a certain level, the treatment liquid overflows into the overflow tank 50; the pump 20 is connected to the overflow tank 50 and the receiving space 100 through pipelines, and can re-inject the treatment liquid in the overflow tank 50 into the receiving space 100 from the liquid inlet 101 to form a cycle. The fixing device 30 is used to fix the material 40 to be treated in the receiving space 100. The stirrer 60 provided in the receiving space 100 is a major feature of the conventional circulation system, but the biggest problem is the accompanying bubbles 70.

[0043] In this comparative example, the capacity of the receiving space 100 is 1.2 L, the flow rate of the treatment liquid generated by the pump 20 is 162 L / hr, and the air intake of the stirrer 60 is 2.2 NLPM. The plating results are as Figures 2A - 2C shown, where the coating thicknesses at two places are 118 nm and 128 nm respectively.

[0044] Example 1

[0045] The first setting of the tank circulation system provided by the present invention is as Figure 3 shown. Different from the conventional circulation system, a stirrer is not used, and the tank 10 further includes a first partition 110, and the first partition 110 divides a receiving space 100 and a first temporary storage space 111 in the tank 10. During operation, a treatment liquid is injected into the receiving space 100, which is also the electroless plating bath in step B10 in this example. The pump 20 is connected to the receiving space 100 and the first temporary storage space 111 through pipelines, and can extract the treatment liquid in the receiving space 100 from the liquid outlet 102 and inject it into the first temporary storage space 111 from the liquid inlet 101. When the liquid level of the treatment liquid in the first temporary storage space is higher than a certain level, the treatment liquid overflows into the receiving space 100 to form a cycle. The fixing device 30 is used to fix the material 40 to be treated in the receiving space 100.

[0046] In some preferred examples, if the material 40 to be processed is a plate-like object and is arranged parallel to the first partition 110, it helps the processing liquid to flow between the plate-like object and the first partition 110. Although the liquid inlet 102 can be arranged anywhere in the accommodation space 100, in some other preferred examples, setting it at the bottom of the accommodation space 100 can also produce a favorable flow effect on the processing liquid.

[0047] In this embodiment, the capacity of the accommodation space 100 is 1.0 L, the capacity of the first temporary storage space is 0.2 L, the flow rate of the processing liquid formed by the pump 20 is 63 L / hr, and the plating results are as Figures 4A - 4C shown, where the plating thicknesses at two places are 426 nm and 339 nm.

[0048] Embodiment 2

[0049] In this embodiment, the capacity of the accommodation space 100 is 1.0 L, the capacity of the first temporary storage space is 0.2 L, which is the same as the setting in Embodiment 1 above. The flow rate of the processing liquid formed by the pump 20 is changed to 162 L / hr, and the plating results are as Figures 5A - 5C shown, where the plating thicknesses at two places are 674 nm and 558 nm respectively.

[0050] Embodiment 3

[0051] The second setting of the tank circulation system provided by the present invention is as Figure 6 shown. Different from the first setting, the tank 10 further includes a second partition 120, and the second partition 120 divides a second temporary storage space 121 in the accommodation space 100. During operation, the processing liquid is also injected into the accommodation space 100, which is also the electroless plating bath in step B10 in this example. The pump 20 is connected to the accommodation space 100 and the second temporary storage space 121 through pipelines, and can draw the processing liquid in the accommodation space 100 out from the liquid outlet 102b and inject it into the second temporary storage space 121 from the liquid inlet 101b. When the liquid level height of the processing liquid in the second temporary storage space 121 is higher than a certain level, the processing liquid overflows into the accommodation space 100 to form a cycle.

[0052] Similarly, if the material 40 to be processed is a plate-like object and is arranged parallel to both the first partition 110 and the second partition 120, it helps the processing liquid to flow between the plate-like object and the first partition 110 and between the plate-like object and the second partition 120.

[0053] In this embodiment, the capacity of the accommodation space 100 is 0.8 L, the capacities of the first temporary storage space 111 and the second temporary storage space 121 are 0.2 L and 0.2 L respectively, the flow rate of the processing liquid formed by the pump 20 is 324 L / hr, and the plating results are as Figures 7A - 7CAs shown, the coating thicknesses at two places are 626 nm and 598 nm respectively.

[0054] After the above description, those skilled in the art can easily determine the necessary features of the present invention, and without departing from the spirit and scope of the present invention, various changes and modifications can be made to the present invention to adapt to various uses and conditions. Any changes and adjustments to the concentration, temperature, pH, and reaction time mentioned within the scope of the patent application should be included within the protection scope of the present invention.

Claims

1. A tank circulation system, characterized in that, it includes: a tank, a circulation pump and a fixing device; the tank has a first partition board, the first partition board divides the tank into a containing space and a first temporary storage space, the height of the first partition board is lower than the tank wall of the side tank of the first temporary storage space; the containing space has a first liquid outlet, the first temporary storage space has a first liquid inlet, both the first liquid outlet and the first liquid inlet are connected to the circulation pump, the liquid flows out from the first liquid outlet and flows into from the first liquid inlet; the fixing device is used to place a material to be processed in the containing space.

2. The tank circulation system according to claim 1, characterized in that, the material to be processed is a plate-shaped object, and the plate-shaped object is arranged parallel to the first partition board.

3. The tank circulation system according to claim 1, characterized in that, the first liquid outlet is arranged below the containing space and is located between the first partition board and the material to be processed.

4. The tank circulation system according to claim 1, characterized in that, the containing space further includes a second partition board, the second partition board divides a second temporary storage space on the opposite side of the first temporary storage space; the height of the second partition board is lower than the tank wall of the side tank of the second temporary storage space; the containing space has a second liquid outlet, the second temporary storage space has a second liquid inlet, both the second liquid outlet and the second liquid inlet are connected to the circulation pump, the liquid flows out from the second liquid outlet and flows into from the second liquid inlet.

5. The tank circulation system according to claim 4, characterized in that, the material to be processed, the first partition board and the second partition board are arranged parallel to each other.

6. The tank circulation system according to claim 4, characterized in that, the second liquid outlet is arranged below the containing space and is located between the second partition board and the material to be processed.

7. A method for etching a circuit board, characterized in that, it is implemented by using the tank circulation system according to any one of claims 1-6, wherein the material to be processed is a circuit board to be etched; an etching solution is injected into the tank.

8. The method for etching a circuit board according to claim 7, characterized in that, the circuit board to be etched has at least one blind hole.

9. A method for electroless plating of a circuit board, characterized in that, it is implemented by using the tank circulation system according to any one of claims 1-6, wherein the material to be processed is a circuit board to be plated; a plating solution is injected into the tank.

10. The method for electroless plating of a circuit board according to claim 9, characterized in that, the circuit board to be plated has at least one blind hole.

11. A method for electroplating a circuit board with electrodes, characterized in that, it is implemented by using the tank circulation system according to any one of claims 1-6, wherein the material to be processed is a circuit board to be plated; a plating solution is injected into the tank.

12. The method for electroplating a circuit board with electrodes according to claim 11, characterized in that, the circuit board to be plated has at least one blind hole.

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