Solder mask blocking point screen printing plate and PCB manufacturing method
By setting the first and second lower ink area in the welding block screen, the problem of ink inlet and development in the small hole size design of double-sided window opening VIA through holes is solved, and efficient welding prevention production and product performance improvement is achieved.
Patent Information
- Application Number
- CN202510032996.2
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2025-01-09
- Publication Date
- 2025-04-18
AI Technical Summary
In the prior art, when designing small holes in double-sided windowed VIA through holes, due to the small hole size, it is difficult to flush out the ink through conventional means once ink is entered, resulting in blockage of holes and affecting the heat dissipation and reliability of the product. Although the conventional large dot mesh design can avoid ink entering the holes, the trace ink at the bottom of the mesh is sticking back to the E-PAD area, which will be baked to death and lead to impurity in development, which will affect the grounding performance of the product.
A welding block-proof screen plate is provided, including a screen plate body, a first lower ink area and a plurality of cover hole areas covered by the VIA through hole of the PCB multi-layer board, and at least one second lower ink area is provided between adjacent cover hole areas. Through this design, when the PCB multilayer board is subjected to solder-proof printing, the first and second lower ink areas are used to print ink, avoiding the problem of false exposure of copper and ink entering the hole.
Welding-proof production of double-sided window opening holes with a hole diameter of <0.4mm is achieved, which avoids problems such as ink entry and unclean development due to too small hole diameter. The performance and stability of PCB board products are improved, and the yield rate of double-sided window opening VIA with small hole diameter is improved.
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Figure CN119855058A_ABST
Abstract
Description
Technical Field
[0001] The embodiments of the present invention relate to the technical field of PCB manufacturing, and in particular to a solder mask screen and a PCB board manufacturing method. Background Art
[0002] There are three types of solder mask ink plugging methods for PCB VIA holes, namely double-sided window holes, full plug holes and half plug holes. Double-sided window holes refer to VIA holes that are not plugged with ink on both sides. Since the inside is completely through and there is no foreign matter such as ink residue, it has better grounding, heat dissipation and performance reliability, and is widely used in the E-PAD area of ICs related to QFA and DQFN packaging.
[0003] In the prior art, when double-sided window VIA through holes are designed with small apertures, once ink enters the holes, it is difficult to flush the ink out by conventional means due to the small aperture. The resulting hole blockage will seriously affect the heat dissipation and reliability of the product. Although the conventional large-block dot mesh design can prevent ink from entering the holes, a small amount of ink at the bottom of the mesh will stick to the E-PAD area, which will be baked to death during pre-baking, resulting in unclean development, and will affect the grounding performance of the product. Summary of the invention
[0004] In view of the above problems, the embodiments of the present invention provide a solder mask screen and a PCB board manufacturing method, which are used to solve the problem that in the prior art, when a double-sided window VIA through hole is designed with a small aperture, once ink enters the hole, it is difficult to flush the ink out by conventional means due to the small aperture, and the resulting hole blockage will seriously affect the heat dissipation and reliability of the product; and although the conventional large-block dot screen design can avoid ink entering the hole, a small amount of ink at the bottom of the screen will stick to the E-PAD area, which will be baked to death during pre-baking, resulting in unclean development, and affecting the grounding performance of the product. According to one aspect of an embodiment of the present invention, a solder mask screen is provided, comprising a screen body, a first ink placement area is arranged on the periphery of the screen body, and a plurality of cover hole areas covering the VIA through holes of a PCB multilayer board are arranged on the inner side of the screen body; at least one second ink placement area is arranged between adjacent cover hole areas; Wherein, the second ink supply area is spaced apart from the cover hole area.
[0005] In some optional embodiments, when the distance between two adjacent cover hole areas is greater than a first preset value, the second ink supply area is set as a lower ink groove, and the lower ink groove is connected to the first ink supply area; the distance between the lower ink groove and the cover hole area is a first preset distance.
[0006] In some optional embodiments, the first preset value is 20 mil; the first preset distance is greater than or equal to 10 mil; and the width of the first ink placement area is 1 mil-3 mil.
[0007] In some optional embodiments, when the distance between two adjacent cover hole areas is less than a first preset value, the second ink lowering area is set as an ink lowering hole, and the distance between the ink lowering hole and the cover hole area is a second preset distance.
[0008] In some optional embodiments, the length and width of the ink hole are both greater than or equal to 10 mil; the first preset value is 20 mil; the second preset distance is greater than or equal to 5 mil; and the width of the first ink area is 1 mil-3 mil.
[0009] According to another aspect of an embodiment of the present invention, a PCB manufacturing method is provided, the method comprising: S1, solder mask printing, obtaining a PCB board and covering the solder mask screen according to any one of claims 1 to 5 on the surface of the PCB board to form a window area, and performing solder mask printing on the non-window area, the first ink area and the second ink area of the PCB multilayer board to form an ink layer; S2, pre-baking, pre-baking the PCB multilayer board with printing ink to form a film on the ink layer of the PCB multilayer board; S3, exposure, placing the pre-baked PCB multilayer board in an exposure machine, and exposing the ink layer by ultraviolet light according to the exposure data to form a solder mask; S4, development, after exposure, use a developing solution to remove the ink layer other than the solder mask layer to complete the solder mask production of the PCB multilayer board.
[0010] In some optional embodiments, in step S1, ink printing is performed by a screen printer at 2.5Kg / cm-3Kg / cm, and the ink layer thickness is 0.5mil-1mil.
[0011] In some optional embodiments, in step S2, the PCB multilayer board is placed in a baking machine and baked at 60° C.-100° C. for 10 min-60 min.
[0012] In some optional embodiments, in step S3, the pre-baked PCB multilayer board is placed in an exposure machine, and a 21-level energy strip is used to expose the 12+ to 13- positions for 2 min-4 min.
[0013] In some optional embodiments, a front process and a back process are also included. The front process is to manufacture the PCB board through the front process before step S1, and the front process specifically includes: cutting, inner layer manufacturing, inner layer AOI, lamination, drilling, and outer layer manufacturing; The post-process is to complete the production of the PCB finished board through the post-process after step S4, and the post-process includes: text, post-baking, surface treatment, molding, testing, and packaging.
[0014] According to another aspect of an embodiment of the present invention, a PCB manufacturing device is provided, wherein the device is used to execute the above-mentioned PCB manufacturing method to manufacture a printed circuit board.
[0015] The invention discloses a solder mask screen and a PCB board manufacturing method, which has the beneficial effects of: 1. The solder mask blocking dot screen provided by the present invention has a first ink placement area on the periphery of the screen body, and a plurality of hole cover areas covering the VIA through holes of the PCB multilayer board are provided on the inner side of the screen body; at least one second ink placement area is provided between adjacent hole cover areas; in particular, the second ink placement area is spaced apart from the hole cover areas. The solder mask blocking dot screen of the present invention can realize the production of solder mask with double-sided window holes with an aperture of less than 0.4mm. When solder mask printing is performed on the PCB multilayer board, ink is printed through the first ink placement area and the second ink placement area. The first ink placement area is used to avoid false copper exposure, and the second ink placement area is used to avoid problems such as ink entering the hole and unclean development due to too small an aperture.
[0016] 2. The PCB board manufacturing method provided by the present invention obtains the PCB board through solder mask printing and covers the solder mask blocking point screen on the surface of the PCB board to form a window area, and performs solder mask printing in the non-window area of the PCB multilayer board, the first ink area and the second ink area to form an ink layer; pre-bake the PCB multilayer board with printed ink to form a film of the ink layer of the PCB multilayer board; expose the pre-baked PCB multilayer board in an exposure machine, and expose the ink layer by ultraviolet rays according to the exposure data to form a solder mask layer; develop and use a developing solution after exposure to remove the ink layer other than the solder mask layer to complete the solder mask production of the PCB multilayer board. The solder mask production on the PCB multilayer board is realized, and the problems of ink entering the hole and incomplete development due to too small aperture are avoided, and the performance and stability of the PCB board product are improved; at the same time, the yield rate of the double-sided window VIA with a small aperture is improved.
[0017] The above description is only an overview of the technical solution of the embodiment of the present invention. In order to more clearly understand the technical means of the embodiment of the present invention, it can be implemented according to the contents of the specification. In order to make the above and other purposes, features and advantages of the embodiment of the present invention more obvious and easy to understand, the specific implementation mode of the present invention is specifically listed below. BRIEF DESCRIPTION OF THE DRAWINGS
[0018] The accompanying drawings are only used to illustrate the embodiments and are not to be considered as limiting the present invention. In addition, the same reference symbols are used to represent the same components throughout the accompanying drawings. In the accompanying drawings: Figure 1 The structure diagram of the solder mask screen of Example 1 provided by the present invention is shown; Figure 2 A schematic flow chart of a method for making a solder mask on a PCB with double-sided window holes according to Embodiment 2 of the present invention is shown; Figure 3 A schematic diagram of a PCB cross section of the printing ink of Example 2 provided by the present invention is shown; Figure 4 A schematic cross-sectional view of an exposed PCB according to Embodiment 2 of the present invention is shown; Figure 5 A schematic cross-sectional view of a developed PCB according to Example 2 provided by the present invention is shown.
[0019] Reference numerals: 1. Cover hole area; 2. Screen body; 3. Ink hole; 4. Ink groove; 5. First ink area; D1. First preset distance; D2. Width of first ink area; D3. Length or width of ink hole; D4. Second preset distance; 10. PCB multilayer board; 11. VIA through hole; 14. Ink layer; 15. Solder mask. DETAILED DESCRIPTION
[0020] Exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although exemplary embodiments of the present invention are shown in the drawings, it should be understood that the present invention can be implemented in various forms and should not be limited to the embodiments set forth herein.
[0021] Embodiment 1: See also Figure 1 The embodiment of the present invention provides a solder mask screen, which is applied to solder mask production of PCB multilayer boards with double-sided window VIA through holes. Specifically, the solder mask screen includes a screen body 2, a first ink-down area 5 is arranged on the periphery of the screen body 2, and a plurality of cover hole areas 1 covering the VIA through holes of the PCB multilayer board are arranged on the inner side of the screen body 2; at least one second ink-down area is arranged between adjacent cover hole areas 1; wherein the second ink-down area is arranged at intervals from the cover hole area 1.
[0022] In this embodiment, the solder mask blocking point screen of the present invention can realize double-sided window holes with an aperture of less than 0.4 mm for solder mask production. When solder mask printing is performed on a multi-layer PCB, ink is printed through the first ink-laying area 5 and the second ink-laying area. The first ink-laying area avoids false copper exposure, and the second ink-laying area avoids problems such as ink entering the hole and incomplete development due to too small an aperture.
[0023] In some optional embodiments, a first ink-down area 5 is provided on the periphery of the stop point screen, and the width of the first ink-down area is 1 mil-3 mil. The position close to the window opening ensures that the stop point is 1-3 mil away from the window opening, thereby avoiding false copper exposure. The width of the first ink-down area is as follows: Figure 1 As shown in D2, it is located outside the blocking point screen, and false copper exposure is avoided by designing the first ink-lowering area 5.
[0024] In some optional embodiments, when the distance between two adjacent cover hole areas 1 is greater than the first preset value, the second ink supply area is set as a lower ink groove 4, and the lower ink groove 4 is connected to the first ink supply area; the distance between the lower ink groove 4 and the cover hole area 1 is the first preset distance D1, see Figure 1 In a specific example, the first preset value is 20mil; the first preset distance D1 is greater than or equal to 10mil; and the width of the first ink supply area is 1mil-3mil. In this embodiment, the lower ink groove 4 is connected to the first ink supply area, and the distance between the lower ink groove 4 and the cover hole area 1 is the first preset distance, so that ink printing can be achieved outside the VIA through hole, thereby avoiding problems such as ink entering the hole and incomplete development due to too small a hole diameter.
[0025] In some optional embodiments, when the distance between two adjacent cover hole areas 1 is less than the first preset value, the second ink lowering area is set as the ink lowering hole 3, and the distance between the ink lowering hole 3 and the cover hole area 1 is the second preset distance D4. In a specific example, the length and width of the ink lowering hole 3 are both greater than or equal to 10 mils. Figure 1 As shown in D3 in the figure; the first preset value is 20mil; the second preset distance D4 is greater than or equal to 5mil; the width of the first ink placement area is 1mil-3mil. In this embodiment, the second ink placement area is the ink placement hole 3, and the ink placement point is cut to ensure that the length and width of the ink placement point are greater than 10mil, and the distance from the ink placement point to the hole edge is ≥5mil. By increasing the amount of ink placement, the development is not clean due to the pre-baking of a trace amount of ink.
[0026] In some optional embodiments, in a solder mask screen, when there are multiple lower cover hole areas 1, and the spacing between the multiple cover hole areas 1 is greater than the first preset value and less than the first preset value at the same time, a lower ink hole 3 and a lower ink groove 4 can be provided at the same time, wherein the first preset distance is greater than or equal to 10mil; the length and width of the lower ink hole 3 are both greater than or equal to 10mil; the first preset value is 20mil; the second preset distance is greater than or equal to 5mil; the width of the first lower ink area is 1mil-3mil. Solder mask production is realized on PCB multilayer boards, avoiding problems such as ink entering the hole and unclean development due to too small aperture, improving the performance and stability of PCB board products; and at the same time improving the yield rate of double-sided window VIA with small aperture.
[0027] Embodiment 2: See also Figure 2-5 According to another aspect of an embodiment of the present invention, a PCB manufacturing method is provided for manufacturing a PCB board having a VIA through hole with a small aperture, the method comprising: S1, solder mask printing, obtain a PCB board and cover the solder mask blocking point screen of Example 1 on the surface of the PCB board to form a window area, and perform solder mask printing on the first ink area and the second ink area in the non-window area of the PCB multilayer board to form an ink layer; in step S1, the solder mask blocking point screen includes a screen body, a first ink area is arranged on the periphery of the screen body, and a plurality of cover hole areas covering the VIA through holes of the PCB multilayer board are arranged on the inner side of the screen body; at least one second ink area is arranged between adjacent cover hole areas; wherein the second ink area is spaced apart from the cover hole area. Ink printing is performed by a screen printer at 2.5Kg / cm-3Kg / cm, and the thickness of the ink layer is 0.5mil-1mil. See. Figure 3 , PCB board after printing ink, such as Figure 3 As shown, 11 is a VIA through hole and 14 is an ink layer.
[0028] S2, pre-baking, pre-baking the PCB multilayer board with printed ink to form a film of the ink layer of the PCB multilayer board; in step S2, the PCB board is placed in a baking machine and baked at 60°C-100°C for 10 min-60 min.
[0029] S3, exposure, put the pre-baked PCB multilayer board in the exposure machine, and expose the ink layer with ultraviolet light according to the exposure data to form a solder mask; in step S3, put the pre-baked PCB board in the exposure machine, use a 21-level strip to expose the 12+ to 13- position, and expose for 2min-4min. Figure 4 , after exposure, the PCB multilayer board, such as Figure 4 As shown, 11 is a VIA through hole, 14 is an ink layer, and 15 is a solder mask layer.
[0030] S4, development, after exposure, use a developing solution to remove the ink layer other than the solder mask layer to complete the solder mask production of the PCB multilayer board. In step S4, the main components of the developing solution include a developer, a protective agent, an accelerator, an inhibitor and a water solvent, wherein the developer can be hydroquinone, metol, phenidone, etc. The developer is the core component of the developer and is responsible for reducing the latent image on the photosensitive material to a visible image. The protective agent can be, for example, sodium sulfite, which is used to prevent the developer from being oxidized during the development process, thereby extending the service life of the developer. The accelerator is usually an alkaline solution, such as sodium hydroxide or sodium carbonate, which is used to accelerate the development reaction. Inhibitors such as 5-methylbenzotriazole, potassium bromide, etc. are used to prevent the photo from generating fog and improve the clarity of the image. Solvent water, as a solvent for the developer, enables the various components to be evenly mixed and act on the photosensitive material. See Figure 5 , after development, the PCB multilayer board, such as Figure 5 As shown, 11 is a VIA through hole, 15 is a solder mask, and 10 is a PCB board.
[0031] The PCB board manufacturing method provided by the present invention obtains the PCB board through solder mask printing and covers the solder mask blocking point screen on the surface of the PCB board to form a window area, and performs solder mask printing in the non-window area of the PCB multilayer board, the first ink area and the second ink area to form an ink layer; pre-bakes the PCB multilayer board with the printed ink to form a film of the ink layer of the PCB multilayer board; exposes the pre-baked PCB multilayer board in an exposure machine, and exposes the ink layer by ultraviolet rays according to the exposure data to form a solder mask layer; develops and uses a developing solution after exposure to remove the ink layer other than the solder mask layer, and completes the solder mask production of the PCB multilayer board. The solder mask production is realized on the PCB multilayer board, avoiding the problems of ink entering the hole and incomplete development due to too small aperture, and improving the performance and stability of the PCB board product; and at the same time, the yield rate of the double-sided window VIA with a small aperture is improved.
[0032] In some optional embodiments, in step S1, ink printing is performed by a screen printer at 2.5Kg / cm-3Kg / cm, and the thickness of the ink layer is 0.5mil-1mil. In this embodiment, the ink screen production can make a screen for printing according to the film pattern to ensure the accuracy and clarity of the pattern. The printing ink uses a screen printer to evenly apply the solder mask ink on the surface of the circuit board. During the coating process, the thickness and uniformity of the ink need to be controlled to ensure the printing quality.
[0033] In some optional embodiments, in step S2, the PCB multilayer board is placed in a baking machine and baked at 60°C-100°C for 10 min-60 min. After the ink is applied, a pre-baking process is required. The purpose of pre-baking is to evaporate the solvent in the ink and form a smooth non-stick film coating state. The temperature and time of pre-baking need to be strictly controlled to avoid excessive hardening or poor development.
[0034] In some optional embodiments, in step S3, the pre-baked PCB board is placed in an exposure machine, and a 21-level strip is used to expose the 12+ to 13- position for 2min-4min. The pre-baked PCB board is placed in an exposure machine, and ultraviolet light is used to expose the ink. During exposure, it is necessary to ensure that the film is closely attached to the PCB board and that oxygen is isolated to accelerate the polymerization reaction. The exposure time and energy need to be adjusted according to the ink type and the characteristics of the PCB board.
[0035] In some optional embodiments, before step S1, a pre-process is also included for making a PCB multilayer board. The pre-process specifically includes: cutting, inner layer production, inner layer AOI, lamination, drilling, and outer layer production. In this embodiment, the pre-processing specifically includes: cutting: cutting the PCB substrate into production size. Cleaning: cleaning the surface of the PCB substrate and removing surface contaminants. Laminating: sticking the dry film on the surface of the PCB substrate to prepare for subsequent image transfer. Exposure: using an exposure device to expose the film-coated substrate with ultraviolet light to transfer the image of the substrate to the dry film. Developing, etching, and film removal: removing the uncured photosensitive film, etching away unnecessary copper foil with a strong alkaline solvent, and completing the production of the inner layer board. AOI optical scanning: comparing the image of the PCB board with the data of the good board to find bad phenomena. VRS detection and maintenance: processing the bad image data detected by AOI, and relevant personnel will perform maintenance. Wire filling: soldering the gold wire on the notch or depression to prevent poor electrical properties. Browning: Increase the adhesion between the board and the resin, and increase the wettability of the copper surface. Riveting: Cut the PP into small sheets and normal sizes, so that the inner layer board can be combined with the corresponding PP. Overlay and pressing: Press multiple inner layer boards into one board. Targeting, edging, and grinding: Process the edges of the board to meet the design requirements. Positioning and drilling: Use a drilling machine to drill holes of different diameters and sizes on the board for subsequent processing of plug-ins and heat dissipation. Graphic processing: Graphically process the outer layer of the PCB, remove excess copper foil by etching, and form the final PCB wire pattern. Electroplating: Plate a layer of copper on the hole wall to ensure reliable conductivity between the layers.
[0036] In some optional embodiments, after step S4, a post-process is also included for making a finished PCB board. The post-process includes: text, post-baking, surface treatment, molding, testing, and packaging in sequence. In this embodiment, the text is printing text on the PCB multilayer board; post-baking is placing the PCB board in a baking device, the baking temperature can be 120-150 degrees, and the baking time can be 30 minutes. The ink of the PCB multilayer board is solidified and fixed. Surface treatment: The side of the bare copper plate to be welded is coated to form a layer of organic film to prevent rust and oxidation. Molding: The board shape required by the customer is produced to facilitate the customer to perform SMT patch and assembly. Testing: Test the board circuit to avoid short-circuit boards from flowing out. It can also include FQC final inspection: After completing all processes, a full sampling inspection is carried out to ensure the quality of the PCB board. Vacuum packaging: The finished PCB board is vacuum packaged to prevent moisture, dust and shock.
[0037] Embodiment 3: According to another aspect of the embodiment of the present invention, a PCB manufacturing device is provided, and the device is used to execute the above-mentioned PCB manufacturing method to manufacture a printed circuit board. The PCB manufacturing device of the present invention is used to execute steps S1-S4 in Example 2, specifically including: obtaining a PCB board through solder mask printing and covering the solder mask blocking point screen on the surface of the PCB board to form a window area, and performing solder mask printing in the non-window area of the PCB multilayer board, the first ink area and the second ink area to form an ink layer; pre-baking the PCB multilayer board with printed ink to form a film of the ink layer of the PCB multilayer board; exposing the pre-baked PCB multilayer board in an exposure machine, and exposing the ink layer by ultraviolet rays according to the exposure data to form a solder mask layer; developing using a developing solution after exposure to remove the ink layer other than the solder mask layer, and completing the solder mask production of the PCB multilayer board. The solder mask production is realized on the PCB multilayer board, avoiding the problems of ink entering the hole and incomplete development due to too small aperture, improving the performance and stability of the PCB board product; at the same time, the yield rate of the double-sided window VIA with a small aperture is improved.
[0038] In the description provided herein, a large number of specific details are described. However, it is understood that embodiments of the present invention can be practiced without these specific details. Similarly, in order to simplify the present invention and help understand one or more of the various inventive aspects, in the above description of exemplary embodiments of the present invention, the various features of the embodiments of the present invention are sometimes grouped together into a single embodiment, figure, or description thereof. Wherein, the claims that follow the specific embodiment are hereby expressly incorporated into the specific embodiment, wherein each claim itself is a separate embodiment of the present invention.
[0039] Those skilled in the art will appreciate that the modules in the devices in the embodiments may be adaptively changed and arranged in one or more devices different from the embodiments. The modules or units or components in the embodiments may be combined into one module or unit or component, and further may be divided into a plurality of submodules or subunits or subcomponents. Except that at least some of such features and / or processes or units are mutually exclusive.
[0040] It should be noted that the above embodiments illustrate the present invention rather than limit it, and that those skilled in the art may design alternative embodiments without departing from the scope of the appended claims. In the claims, any reference symbol between brackets shall not be construed as a limitation on the claims. The word "comprising" does not exclude the presence of elements or steps not listed in the claims. The word "one" or "an" preceding an element does not exclude the presence of multiple such elements. The present invention may be implemented with the aid of hardware comprising several different elements and with the aid of appropriately programmed computers. In a unit claim that lists several systems, several of these systems may be embodied by the same hardware item. The use of the words first, second, and third, etc. does not indicate any order. These words may be interpreted as names. The steps in the above embodiments, unless otherwise specified, should not be understood as limitations on the order of execution.
Claims
1. A solder mask screen, characterized in that: It comprises a screen body, wherein a first ink placement area is arranged on the periphery of the screen body, and a plurality of cover hole areas covering the VIA through holes of the PCB multilayer board are arranged on the inner side of the screen body; at least one second ink placement area is arranged between adjacent cover hole areas; Wherein, the second ink supply area is spaced apart from the cover hole area.
2. The solder mask screen according to claim 1, characterized in that: When the distance between two adjacent cover hole areas is greater than a first preset value, the second ink supply area is set as a lower ink groove, and the lower ink groove is connected to the first ink supply area; the distance between the lower ink groove and the cover hole area is a first preset distance.
3. The solder mask screen according to claim 2, characterized in that: The first preset value is 20 mil; the first preset distance is greater than or equal to 10 mil; and the width of the first ink application area is 1 mil-3 mil.
4. The solder mask screen according to claim 1, characterized in that: When the distance between two adjacent cover hole areas is less than a first preset value, the second ink lowering area is set as an ink lowering hole, and the distance between the ink lowering hole and the cover hole area is a second preset distance.
5. The solder mask screen according to claim 4, characterized in that: The length and width of the ink delivery hole are both greater than or equal to 10 mil; the first preset value is 20 mil; the second preset distance is greater than or equal to 5 mil; and the width of the first ink delivery area is 1 mil-3 mil.
6. A PCB manufacturing method, characterized in that: The method comprises: S1, solder mask printing, obtaining a PCB board and covering the solder mask screen according to any one of claims 1 to 5 on the surface of the PCB board to form a window area, and performing solder mask printing on the non-window area, the first ink area and the second ink area of the PCB multilayer board to form an ink layer; S2, pre-baking, pre-baking the PCB multilayer board with printing ink to form a film on the ink layer of the PCB multilayer board; S3, exposure, placing the pre-baked PCB multilayer board in an exposure machine, and exposing the ink layer by ultraviolet light according to the exposure data to form a solder mask; S4, development, after exposure, use a developing solution to remove the ink layer other than the solder mask layer to complete the solder mask production of the PCB multilayer board.
7. The method for making solder mask on a PCB with double-sided window holes according to claim 6, characterized in that: In step S1, ink printing is performed by a screen printer at 2.5 Kg / cm-3 Kg / cm, and the thickness of the ink layer is 0.5 mil-1 mil.
8. The method for making solder mask on a PCB with double-sided window holes according to claim 6, characterized in that: In step S2, the PCB multilayer board is placed in a baking machine and baked at 60° C.-100° C. for 10 min-60 min.
9. The method for making solder mask on a PCB with double-sided window holes according to claim 6, characterized in that: In step S3, the pre-baked PCB multilayer board is placed in an exposure machine, and a 21-level energy strip is used to expose the 12+ to 13- positions for 2 minutes to 4 minutes.
10. The method for making solder mask on a PCB with double-sided window holes according to claim 6, characterized in that: It also includes the front process and the back process. The front process is to manufacture the PCB board through the front process before step S1, and the front process specifically includes: cutting, inner layer manufacturing, inner layer AOI, lamination, drilling, and outer layer manufacturing; The post-process is to complete the production of the PCB finished board through the post-process after step S4, and the post-process includes: text, post-baking, surface treatment, molding, testing, and packaging.