Manufacturing method of printed circuit board with solder mask and printed circuit board

Abstract

The invention discloses a manufacturing method of a printed circuit board with a solder mask and the printed circuit board, and relates to the technical field of printed circuit board processing, the method comprises the following steps: step groove processing, specifically comprising core board processing, resistance adhesive film pasting, pressing and depth-controlled uncovering; coating solder resist in the step groove; and performing laser engraving to expose a welding pad, and processing a finished product. According to the scheme, the mode that the step groove is machined firstly and then the step groove is coated with the solder mask is adopted, and the problems that in the traditional step groove machining process, the solder mask pattern is manufactured before press fit, the solder mask pattern is exposed through uncovering after press fit, and solder mask discoloration and falling are caused by the high-temperature press fit procedure are solved.

Description

Technical Field

[0001] The invention relates to the technical field of printed circuit board manufacturing in the processing and manufacturing of electronic components, and in particular to a method for manufacturing a printed circuit board with solder resist. Background Art

[0002] With the development of electronic products, the demand for multifunctional products is getting higher and higher. In order to improve product performance, product assembly density, and reduce product weight and volume, PCB manufacturing has also changed. At present, a new processing technology is the step groove process. The main feature of the step groove process is that the components are welded in the printed board, which can reduce the package size of the PCBA.

[0003] In order to weld, solder mask patterns also need to be made in the step groove. The current conventional solder mask processing method is to complete the solder mask pattern before lamination, and then expose the solder mask pattern through the process of uncovering after lamination. The problem with this processing flow is that the printed circuit board will experience a high temperature process for several hours during the lamination process. The high temperature will cause the solder mask ink to change color, and the bonding strength between the solder mask and the printed circuit board will deteriorate, with the risk of falling off. Summary of the invention

[0004] In order to solve the risk of solder resist falling off during the process of manufacturing PCB boards using conventional solder resist processing technology, the present invention provides a method for manufacturing a printed circuit board with solder resist.

[0005] The manufacturing method provided by the present invention comprises: Step groove processing: core board processing, adhesive film pasting, lamination, depth control and cover removal processes are carried out in sequence to produce the step groove structure; Among them, the resist film pasting process is to paste a resist film of the same size as the step groove on the surface of the step exposure layer; because the resist film pasting process is located before the process, the resist film blocks the bonding of the prepreg PP and the core board during the lamination process; after lamination, the substrate at the step position is peeled off in a depth-controlled manner to expose the resist film, and after peeling off the resist film, the circuit pattern in the step is exposed to obtain the step groove; Coating solder resist: Use electrostatic spraying process to coat solder resist in the step groove; the thickness of the sprayed solder resist is 10-30μm; Laser engraving: Use laser to ablate and remove solder resist at the position where a window needs to be opened in the step groove to expose the pad for welding; further, select laser in the natural light band to effectively avoid laser damage to the copper circuit of the printed circuit board; Finished product processing: After the processes of text, surface treatment, molding and testing, the finished printed circuit board is obtained.

[0006] The present invention provides a printed circuit board, which is manufactured by adopting the manufacturing method of the printed circuit board.

[0007] The method for manufacturing a printed circuit board with solder resist proposed in the present invention processes the solder resist after the step groove is completed, thereby avoiding the problem of solder resist discoloration and shedding caused by the high-temperature pressing process during the traditional step groove processing process, in which the solder resist pattern is completed before pressing and the solder resist pattern is exposed by uncovering after pressing. At the same time, the solder resist is coated in the step groove by electrostatic spraying, and the coating thickness is uniform and the adhesion is strong. The laser ablation accuracy is extremely high, which is conducive to the welding of components. BRIEF DESCRIPTION OF THE DRAWINGS

[0008] Figure 1 This is a schematic diagram of the cross-sectional structure of the PCB after step groove processing; Figure 2 It is a schematic diagram of the cross-sectional structure of the PCB after coating with solder resist; Figure 3 This is a schematic diagram of the cross-sectional structure of the PCB after laser window opening. DETAILED DESCRIPTION

[0009] In order to enable those skilled in the art to better understand the technical solution of the present invention, the product of the present invention is further described in detail below with reference to examples and drawings.

[0010] This embodiment provides a method for manufacturing a printed circuit board with solder mask, comprising the following steps: S1, processing a step groove: sequentially performing core board processing, resist film pasting, lamination, and depth-controlled uncovering to manufacture a step groove structure; After the core board is processed, a resist film of the same size as the step groove is pasted on the surface of the step exposure layer. The resist film blocks the bonding of the prepreg PP and the core board in the subsequent lamination process; after lamination, the substrate at the step position is peeled off in a depth-controlled manner to expose the resist film, and the step groove is obtained by peeling off the resist film to expose the circuit pattern in the step, such as Figure 1 As shown; S2, coating solder resist: coating solder resist in the step groove; preferably using electrostatic spraying process, the thickness of the sprayed solder resist is 10-30μm; after processing Figure 2 As shown; S3, Laser engraving: Use laser to ablate and remove the solder resist at the position where the window needs to be opened in the step groove to expose the solder pad for welding; Figure 3 As shown; it is preferred to use lasers in the natural light band to effectively avoid laser damage to the copper circuits of the printed circuit board; S4, finished product processing: After the text, surface treatment, molding and testing processes in sequence, the finished printed circuit board is obtained.

[0011] The above embodiments are only used to illustrate the technical ideas and features of the present invention, and are not intended to be the only or limit the present invention. It should be understood by those skilled in the art that various changes or equivalent substitutions made to the present invention without departing from the scope of the present invention all fall within the scope of protection of the present invention.

Claims

1. A method for manufacturing a printed circuit board with solder mask, characterized in that: The method comprises: S1. Step groove processing: the step groove structure is manufactured by sequentially processing the core board, pasting the blocking film, pressing, and controlling the depth of the cover; S2. Solder resist coating: Use spraying process to coat solder resist in the step groove; S3, Laser engraving: Use laser to ablate and remove solder resist at the position where a window needs to be opened in the step groove to expose the pad for welding; S4, finished product processing: the finished printed circuit board is obtained through the processes of text, surface treatment, molding and testing.

2. The method according to claim 1, characterized in that In step S1, the resist film is pasted on the surface of the exposed layer of the step of the core board with a resist film of the same size as the step groove. After lamination, the substrate at the step position is peeled off in a depth-controlled manner to expose the resist film, and the resist film is peeled off to expose the circuit pattern in the step to obtain the step groove.

3. The method according to claim 1, characterized in that The solder resist coating process in step S2 is electrostatic spraying, and the thickness of the sprayed solder resist is 10-30 μm.

4. The method according to claim 1, characterized in that: The laser in step S3 is selected from the natural light band.

5. A printed circuit board, characterized in that: The printed circuit board is manufactured by the method for manufacturing a printed circuit board with solder resist as described in any one of claims 1 to 4.

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