Processing method for improving skip plating of platinum plated on PCB (Printed Circuit Board)

Abstract

The invention discloses a processing method for improving PCB platinum plating skip plating, and belongs to the technical field of PCB platinum plating. According to the processing method for improving PCB platinum plating skip plating, the original technological process is optimized, a window is formed in the position of a platinum disc in the external light imaging step, the platinum disc is made to be far away from the edge of the window of a dry film, the perimeter of the edge of the dry film is reduced, and the thickness of the dry film is reduced; therefore, the hydrogen is effectively prevented from being attached to the edge of the dry film to influence the platinum plating effect of the position of the platinum disc, the hydrogen generated in the platinum plating process can effectively escape, and alkaline etching is performed before platinum plating, so that the position of the platinum disc can be etched firstly, then platinum plating is performed, and finally alkaline etching is performed to etch a normal circuit. Through optimization of the technological process, the reworking time caused by skip plating can be shortened, and the production progress is improved.

Description

Technical Field

[0001] The invention relates to the technical field of platinum plating on PCB boards, and in particular to a processing method for improving platinum plating leakage on PCB boards. Background Art

[0002] Platinum PCB is a high-performance printed circuit board with a surface treated with platinum to improve corrosion resistance and conductivity. This treatment makes the circuit board more stable in high temperature and harsh environments, suitable for advanced electronic devices and applications requiring extremely high reliability.

[0003] Platinum PCB boards are used as medical blood index detection products, and the market demand is very large. However, such products have very strict requirements on appearance, especially platinum plates cannot have any defects. During the platinum plating process, due to the low efficiency of platinum plating, some side reactions occur, causing hydrogen ions to discharge and precipitate hydrogen at the cathode, generating a large amount of hydrogen gas. The small bubbles produced will adhere to the edge of the dry film, making it impossible for the coating to be deposited normally, resulting in leakage plating, and making it impossible for the coating to be deposited normally. Summary of the invention

[0004] The purpose of the present invention is to solve at least one of the technical problems existing in the prior art. To this end, the present invention provides a processing method for improving platinum leakage plating on PCB boards, which can improve the phenomenon of platinum leakage plating on PCB boards.

[0005] The method for improving platinum leakage plating on a PCB board according to an embodiment of the present invention comprises the following steps:

[0006] Step 1: Perform pre-processing on the PCB board to form the basic structure of the PCB board;

[0007] Step 2: Gold-plating the PCB board. After the gold-plating is completed, the dry film in the non-gold-plated area is removed to expose the area that needs to be plated with platinum;

[0008] Step 3: Open a window at the location of the platinum disk through external light imaging;

[0009] Step 4: Perform the first alkaline etching to remove the copper surface not protected by the resist layer;

[0010] Step 5: Sandblast the surface of the PCB board;

[0011] Step 6: Platinum-plated PCB board, after platinum plating is completed, remove the dry film in the non-platinum-plated area;

[0012] Step 7: Perform a second alkaline etching to form a circuit pattern.

[0013] The processing method for improving platinum leakage plating on PCB boards according to the embodiment of the present invention has at least the following beneficial effects: in the external light imaging step, a window is opened at the position of the platinum disk, so that the platinum disk is away from the edge of the dry film window, and the perimeter of the edge of the dry film is reduced, thereby effectively preventing hydrogen from adhering to the edge of the dry film and affecting the platinum plating effect at the position of the platinum disk. The hydrogen generated during the platinum plating process can effectively escape, and the scrap rate of platinum leakage plating is reduced from the previous average of 6.26% to 0%, which completely solves the leakage plating problem caused by hydrogen evolution.

[0014] According to some embodiments of the present invention, in step 1, the pre-processing further includes cleaning the substrate by ultrasonic cleaning to remove contaminants on the surface.

[0015] According to some embodiments of the present invention, in step 1, the surface of the substrate is treated by pickling.

[0016] According to some embodiments of the present invention, in step 5, the sandblasting process sprays abrasives onto the surface of the PCB board through compressed air to remove oxide scale and oil stains and increase surface roughness.

[0017] According to some embodiments of the present invention, in the first alkaline etching step, the platinum disk location is etched.

[0018] According to some embodiments of the present invention, in the second alkaline etching step, the normal circuits are etched.

[0019] According to some embodiments of the present invention, in step 3, there is a uniform gap between the edge of the through window and the edge of the platinum disk.

[0020] Additional aspects and advantages of the present invention will be given in part in the following description and in part will be obvious from the following description, or will be learned through practice of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The present invention is further described below in conjunction with the accompanying drawings and embodiments:

[0022] Figure 1 It is a flow chart of a processing method for improving platinum leakage plating on a PCB board according to an embodiment of the present invention;

[0023] Figure 2 It is a schematic diagram of opening a window in the external light imaging step.

[0024] Reference numerals:

[0025] 1 platinum plate; 2 through windows. DETAILED DESCRIPTION

[0026] This section will describe in detail the specific embodiments of the present invention. The preferred embodiments of the present invention are shown in the accompanying drawings. The purpose of the accompanying drawings is to supplement the description of the text part of the specification with graphics, so that people can intuitively and vividly understand each technical feature and the overall technical solution of the present invention, but it cannot be understood as a limitation on the scope of protection of the present invention.

[0027] In the description of the present invention, it should be understood that descriptions involving orientations, such as up, down, front, back, left, right, etc., and orientations or positional relationships indicated are based on the orientations or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore should not be understood as a limitation on the present invention.

[0028] In the description of the present invention, "several" means one or more, "more" means more than two, "greater than", "less than", "exceed" etc. are understood as not including the number itself, and "above", "below", "within" etc. are understood as including the number itself. If there is a description of "first" or "second", it is only used for the purpose of distinguishing the technical features, and cannot be understood as indicating or implying the relative importance or implicitly indicating the number of the indicated technical features or implicitly indicating the order of the indicated technical features.

[0029] In the description of the present invention, unless otherwise clearly defined, terms such as setting, installing, connecting, etc. should be understood in a broad sense, and technicians in the relevant technical field can reasonably determine the specific meanings of the above terms in the present invention based on the specific content of the technical solution.

[0030] refer to Figure 1 and Figure 2 A processing method for improving platinum-gold leakage plating on a PCB board according to an embodiment of the present invention is described.

[0031] like Figure 1 and Figure 2 As shown, the processing method for improving platinum leakage plating of PCB board according to the embodiment of the present invention includes:

[0032] Step 1: Perform pre-processing on the PCB board to form the basic structure of the PCB board;

[0033] Step 2: Gold-plating the PCB board. After the gold-plating is completed, the dry film in the non-gold-plated area is removed to expose the area that needs to be plated with platinum;

[0034] Step 3: Open window 2 at the position of platinum disk 1 through external light imaging;

[0035] Step 4: Perform the first alkaline etching, using an alkaline etching solution to etch the PCB surface to remove the copper surface that is not protected by the anti-corrosion layer;

[0036] Step 5: Sandblast the surface of the PCB board;

[0037] Step 6: Platinum-plated PCB board, after platinum plating is completed, remove the dry film in the non-platinum-plated area;

[0038] Step 7: Perform a second alkaline etching, using an alkaline etching solution to etch the PCB surface to form a circuit pattern.

[0039] like Figure 1 and Figure 2 As shown, in the external light imaging step, a window 2 is opened at the position of the platinum disk 1. In the first alkaline etching step, the position of the platinum disk 1 is etched. In the second alkaline etching step, the normal circuit is etched. In the existing platinum plating process, the external light imaging step only opens a window for the platinum disk 1, and in the process of platinum plating, hydrogen ions are discharged on the board surface to produce hydrogen, and small bubbles will adhere to the edge of the dry film and are difficult to remove by vibration, swinging, etc., so that the coating cannot be deposited normally, resulting in leakage plating. In the present processing method for improving the leakage platinum plating of PCB board, the external light imaging step opens a window 2 at the position of the platinum disk 1, so that the platinum disk 1 is away from the edge of the dry film window, and the perimeter of the edge of the dry film is reduced, thereby effectively avoiding hydrogen from adhering to the edge of the dry film to affect the platinum plating effect at the position of the platinum disk 1, and the hydrogen generated during the platinum plating process can effectively escape, and the scrap rate of leakage plating of the platinum disk 1 has dropped from the previous average of 6.26% to 0%, which completely solves the leakage plating problem caused by hydrogen evolution. There is a uniform gap between the edge of the through window and the edge of the platinum plate. The uniform gap can further prevent hydrogen from adhering to the edge of the dry film, thereby further ensuring the completeness of the platinum plating.

[0040] In the existing platinum plate 1 processing technology, the copper at the bottom of the pad is not conducive to the effective escape of hydrogen. In the present processing method for improving platinum plating leakage of PCB board, an additional first alkaline etching is performed on the position of the platinum plate 1. When platinum is plated, platinum will be plated on the edge of the pad, making the platinum plate 1 more corrosion-resistant, reducing the generation of hydrogen during the platinum plating process, thereby reducing the impact of hydrogen on the platinum plating process.

[0041] like Figure 1 As shown, the processing method for improving platinum leakage plating on PCB boards first uses ultrasonic cleaning to clean the substrate before gold plating to remove surface dirt, grease and other contaminants. The substrate surface is treated by pickling or other methods to increase its roughness to increase the adhesion of the coating in subsequent processes.

[0042] like Figure 2 As shown, in step 3, the external light imaging step, the window 2 is opened on the dry film at the position of the platinum disk 1 by photolithography technology. In this step, special attention is paid to keeping the platinum disk 1 away from the edge of the dry film window and reducing the perimeter of the dry film edge, so as to effectively prevent hydrogen from adhering to the edge of the dry film and affecting the platinum plating effect at the position of the platinum disk 1.

[0043] In the sandblasting step, the substrate is sandblasted by a sandblasting machine to increase the surface roughness. This improves the adhesion of the electroplated platinum layer. The sandblasting process ensures that the platinum coating can be evenly adhered to the target area. In the next process step, after the electroplating platinum and the second alkaline etching step are completed, subsequent processing is carried out, including inspection, testing, and other necessary processing steps. These steps ensure that the quality, performance, and reliability of the circuit board meet the standards.

[0044] In summary, the present method for improving platinum leakage plating on PCB optimizes the original process flow, that is, alkaline etching is performed before platinum electroplating, so that the position of the platinum plate 1 can be etched out first, and then platinum is electroplated, and finally alkaline etching is performed to etch the normal circuit. This optimization of the process flow can reduce the time of rework due to leakage plating and improve production progress.

[0045] The embodiments of the present invention are described in detail above with reference to the accompanying drawings, but the present invention is not limited to the above embodiments, and various changes can be made within the knowledge scope of ordinary technicians in the technical field without departing from the purpose of the present invention.

Claims

1. A method for improving platinum leakage plating on PCB, characterized in that: The following steps are involved: Step 1: Perform pre-processing on the PCB board to form the basic structure of the PCB board; Step 2: Gold-plating the PCB board. After the gold-plating is completed, the dry film in the non-gold-plated area is removed to expose the area that needs to be plated with platinum; Step 3: Open a window at the location of the platinum disk through external light imaging; Step 4: Perform the first alkaline etching to remove the copper surface not protected by the resist layer; Step 5: Sandblast the surface of the PCB board; Step 6: Platinum-plated PCB board, after platinum plating is completed, remove the dry film in the non-platinum-plated area; Step 7: Perform a second alkaline etching to form a circuit pattern.

2. The method for improving platinum leakage of PCB board according to claim 1, characterized in that: In step 1, the pre-process treatment also includes cleaning the substrate by ultrasonic cleaning to remove contaminants on the surface.

3. The method for improving platinum leakage plating on PCB board according to claim 2, characterized in that: In step 1, the surface of the substrate is treated by pickling.

4. The method for improving platinum leakage plating on PCB board according to claim 1, characterized in that: In step 5, sandblasting uses compressed air to spray abrasives onto the surface of the PCB board to remove oxide scale and oil stains and increase surface roughness.

5. The method for improving platinum leakage of PCB board according to claim 1, characterized in that: In the first alkaline etching step, the platinum disk locations were etched.

6. The method for improving platinum leakage of PCB board according to claim 1, characterized in that: In the second alkaline etching step, the normal lines are etched.

7. The method for improving platinum leakage of PCB board according to claim 1, characterized in that: In step 3, there is a uniform gap between the edge of the through window and the edge of the platinum disk.

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