Manufacturing method of high-precision step circuit board and high-precision step circuit board

Abstract

The invention provides a manufacturing method of a high-precision step circuit board and the high-precision step circuit board, belongs to the technical field of circuit board manufacturing, and solves the problems of low production efficiency and poor product performance and quality of the high-precision step circuit board. The method comprises the following steps: providing a first substrate and a second substrate; performing first pretreatment on the first substrate to obtain a first substrate to be laminated, the first substrate having a milling groove position; performing second pretreatment on the second substrate to obtain a to-be-pressed second substrate; pressing the first substrate to be pressed and the second substrate to be pressed to obtain a pressed substrate with steps; performing third pretreatment on the laminated substrate with the step to obtain a substrate after the third pretreatment; and carrying out forming treatment on the substrate after the third pretreatment to obtain the high-precision step circuit board. According to the scheme, the circuit board is firstly manufactured in a layered mode, then pressing and forming treatment are conducted, efficient production and manufacturing of the high-precision step circuit board are achieved, and the product performance quality is improved.

Description

Technical Field

[0001] The present invention relates to the technical field of circuit board manufacturing, and in particular to a manufacturing method of a high-precision step circuit board and a high-precision step circuit board. Background Art

[0002] In recent years, with the development of electronic products towards multifunctionality, miniaturization and lightness, the market demand for high-end and key printed circuit board products such as high-frequency, high-speed, high-rise and high-density printed circuit boards, integrated circuit packaging substrates, and special printed circuit boards has been increasing. At the same time, for higher density integration and smaller electronic devices, more electronic components need to be integrated in a limited space, which not only promotes the reduction of equipment size, but also puts forward higher requirements for realizing more functions and more complex circuit designs in a limited area.

[0003] However, currently, when manufacturing step circuit boards, glue overflow is easily generated, which in turn contaminates the circuits in the step grooves, resulting in low production efficiency and poor product performance and quality of high-precision step circuit boards. Summary of the invention

[0004] The present invention provides a method for manufacturing a high-precision step circuit board and a high-precision step circuit board, which solve the problems of low production efficiency and poor product performance and quality of the high-precision step circuit board.

[0005] In order to solve the above technical problems, the technical solution of the present invention is as follows:

[0006] An embodiment of the present invention provides a method for manufacturing a high-precision stepped circuit board, comprising:

[0007] providing a first substrate and a second substrate;

[0008] Performing a first pretreatment on the first substrate to obtain a first substrate to be pressed, wherein the first substrate has a groove position;

[0009] Performing a second pretreatment on the second substrate to obtain a second substrate to be pressed;

[0010] Performing a lamination process on the first substrate to be laminarized and the second substrate to be laminarized to obtain a laminar substrate with a step, wherein the gong groove is in contact with the second substrate;

[0011] Performing a third pretreatment on the laminated substrate with the step to obtain a substrate after the third pretreatment;

[0012] The substrate after the third pretreatment is subjected to a molding process to obtain a high-precision step circuit board.

[0013] Optionally, performing a first pretreatment on the first substrate to obtain a first substrate to be pressed includes:

[0014] Cutting the first substrate according to first preset cutting parameters to obtain a cut first substrate;

[0015] Performing a drilling process on the cut first substrate to obtain a drilled first substrate;

[0016] The first substrate after drilling is subjected to grinding, lamination, exposure and development processes to obtain a first substrate with an anti-corrosion protection layer;

[0017] Performing an etching and film stripping process on the first substrate formed with the anti-corrosion protection layer to obtain a first substrate formed with circuits;

[0018] Performing adhesive film treatment on the first substrate on which the circuit is formed to obtain a first substrate with an adhesive film;

[0019] The first substrate with the adhesive film is subjected to a groove opening process to obtain a first substrate to be pressed.

[0020] Optionally, performing a second pretreatment on the second substrate to obtain a second substrate to be pressed includes:

[0021] Cutting the second substrate according to second preset cutting parameters to obtain a cut second substrate;

[0022] Performing a drilling process on the cut second substrate to obtain a drilled second substrate;

[0023] The drilled second substrate is subjected to grinding, lamination, exposure and development processes to obtain a second substrate with an anti-corrosion protection layer;

[0024] The second substrate with the anti-corrosion protection layer formed thereon is subjected to an etching and film stripping treatment to obtain a second substrate to be laminated.

[0025] Optionally, performing a lamination process on the first substrate to be laminated and the second substrate to be laminated to obtain a laminated substrate having steps, comprises:

[0026] Performing a browning treatment on the second substrate to be pressed to obtain a browned second substrate;

[0027] Performing a stacking and riveting process on the browned second substrate and the grooves of the first substrate to obtain a stacked and riveted substrate;

[0028] The substrate after the stacked plates are riveted is pressed to obtain a pressed substrate with steps.

[0029] Optionally, performing a third pretreatment on the laminated substrate having the step to obtain the substrate after the third pretreatment includes:

[0030] Performing drilling processing on the pressed substrate to obtain a drilled substrate;

[0031] Performing copper deposition on the drilled substrate to obtain a copper-deposited substrate;

[0032] Performing electroplating treatment on the copper-plated substrate to obtain an electroplated substrate;

[0033] The substrate after the plate electroplating is subjected to a copper coating etching process to obtain a substrate after the third pretreatment.

[0034] Optionally, the substrate after the plate electroplating is subjected to copper coating etching to obtain a substrate after the third pretreatment, comprising:

[0035] The substrate after electroplating is subjected to grinding, lamination, exposure and development processes to obtain a substrate with an anti-corrosion protection layer;

[0036] Performing micro-etching treatment on the substrate formed with the anti-corrosion protection layer to obtain a substrate formed with circuits;

[0037] Performing a film stripping process on the substrate on which the circuit is formed to obtain a film stripped substrate;

[0038] The substrate after film stripping is subjected to electroplating and etching treatment to obtain a substrate after the third pretreatment.

[0039] Optionally, the substrate after film stripping is subjected to electroplating and etching treatment to obtain a substrate after a third pretreatment, comprising:

[0040] The substrate after the film stripping is subjected to grinding, lamination, exposure and development treatments to obtain a substrate with an anti-corrosion protective layer;

[0041] Performing pattern electroplating on the substrate formed with the anti-corrosion protection layer to obtain a pattern electroplated substrate;

[0042] The substrate after pattern electroplating is etched to obtain a substrate after a third pretreatment.

[0043] Optionally, the substrate after the third pretreatment is subjected to a molding process to obtain a high-precision step circuit board, comprising:

[0044] performing optical inspection on the substrate after the third pretreatment to obtain a substrate after optical inspection;

[0045] Performing solder mask text processing on the substrate after the optical inspection to obtain a substrate after the solder mask text processing;

[0046] Performing surface gold immersion treatment on the substrate after the solder mask text processing to obtain a substrate after the surface gold immersion treatment;

[0047] The substrate with the surface immersion gold is cut and formed to obtain a high-precision step circuit board.

[0048] Optionally, the method for manufacturing the highly integrated half-hole step circuit board further includes:

[0049] The high-precision step circuit board is tested and inspected according to preset test conditions to obtain a qualified high-precision step circuit board; the preset test conditions include at least one of the following conditions:

[0050] Open circuit and short circuit test conditions, test voltage is 20~500V, test current is 5~200mA, continuity test range is 2~10000ohm, insulation test range is 5~500Mohm, equivalent test range is 0.1pF~10mF, ambient temperature is 22℃~26℃.

[0051] An embodiment of the present invention further provides a high-precision stepped circuit board, which is prepared by the above method.

[0052] The technical solution of the present invention includes at least the following effects:

[0053] The above scheme of the present invention provides a first substrate and a second substrate; performs a first pretreatment on the first substrate to obtain a first substrate to be pressed; performs a second pretreatment on the second substrate to obtain a second substrate to be pressed; performs a pressing treatment on the first substrate to be pressed and the second substrate to be pressed to obtain a pressed substrate; performs a third pretreatment on the pressed substrate to obtain a third pretreated substrate; and performs a molding treatment on the third pretreated substrate to obtain a high-precision step circuit board. The scheme realizes the efficient production of high-precision step circuit boards by first layering the circuit boards and then performing the pressing and molding treatments, thereby improving the product performance and quality. BRIEF DESCRIPTION OF THE DRAWINGS

[0054] Figure 1 is a flow chart of a method for manufacturing a high-precision stepped circuit board provided by an embodiment of the present invention;

[0055] Figure 2 is a cross-sectional view of a high-precision step circuit board provided by an embodiment of the present invention;

[0056] Among them, 1. first substrate; 2. second substrate; 3. first circuit layer; 4. via hole; 5. AD film layer; 6. second circuit layer. DETAILED DESCRIPTION

[0057] The exemplary embodiments of the present invention will be described in more detail below with reference to the accompanying drawings. Although the exemplary embodiments of the present invention are shown in the accompanying drawings, it should be understood that the present invention can be implemented in various forms and should not be limited by the embodiments set forth herein. On the contrary, these embodiments are provided in order to enable a more thorough understanding of the present invention and to enable the scope of the present invention to be fully communicated to those skilled in the art.

[0058] like Figure 1 As shown, an embodiment of the present invention provides a method for manufacturing a high-precision step circuit board, comprising:

[0059] Step 11, providing a first substrate and a second substrate;

[0060] Step 12, performing a first pretreatment on the first substrate to obtain a first substrate to be pressed, wherein the first substrate has a gong groove position;

[0061] Step 13, performing a second pretreatment on the second substrate to obtain a second substrate to be pressed;

[0062] Step 14, performing a lamination process on the first substrate to be laminated and the second substrate to be laminated to obtain a laminated substrate with steps, wherein the gong groove is laminated with the second substrate;

[0063] Step 15, performing a third pretreatment on the laminated substrate with steps to obtain a substrate after the third pretreatment;

[0064] Step 16, performing molding processing on the substrate after the third pretreatment to obtain a high-precision step circuit board.

[0065] In this example, first, two substrates are prepared as the basic materials for manufacturing circuit boards. These substrates are usually made of insulating materials, such as epoxy resin, glass fiber, etc., to meet the subsequent circuit design and functional requirements. The first substrate and the second substrate are made of the same material; according to the design requirements, the thickness and size may vary, such as the first substrate is 3 mm thick and the second substrate is 2 mm thick; the pretreatment step is to ensure that the substrate surface is clean and flat, and has good adhesion, specifically including cutting, drilling positioning holes, forming an anti-corrosion layer, etching, sticking a film, gong grooves and other steps; after these pretreatment steps, the first substrate is ready for the subsequent pressing operation; with the first substrate Similarly, the second substrate also needs to undergo a pretreatment step to ensure that its surface is clean, flat and has good adhesion; after pretreatment, the first substrate and the second substrate can be pressed together; during the pressing process, the pretreated first substrate and the second substrate are first tightly combined together through a pressing device; after the pressing is completed, a third pretreatment is required, which specifically includes drilling positioning holes, copper plating, whole-board electroplating, etching and other steps to form a copper layer on the surface of the substrate to meet the conductivity requirements of the circuit design; then the substrate after the third pretreatment is processed into the final required shape and size, including cutting, polishing and other steps. After the molding process, the final high-precision step circuit board is obtained.

[0066] The above technical solution of the present invention solves the problems of low production efficiency and poor product performance and quality of high-precision step circuit boards by first manufacturing the circuit boards in layers and then performing pressing and molding processes, thereby realizing the efficient production of high-precision step circuit boards and improving product performance and quality.

[0067] In an optional embodiment of the present invention, step 12 may include:

[0068] Step 121, cutting the first substrate according to first preset cutting parameters to obtain a cut first substrate;

[0069] Step 122, drilling the cut first substrate to obtain a drilled first substrate;

[0070] Step 123, performing grinding, lamination, exposure and development processes on the first substrate after drilling to obtain a first substrate with an anti-corrosion protection layer formed thereon;

[0071] Step 124, performing an etching and film stripping process on the first substrate formed with the anti-corrosion protection layer to obtain a first substrate formed with circuits;

[0072] Step 125, performing adhesive film treatment on the first substrate with the circuit formed thereon to obtain a first substrate with an adhesive film;

[0073] Step 126, performing a groove processing on the first substrate with the adhesive film to obtain a first substrate to be pressed.

[0074] In this example, the first substrate is firstly cut according to the first preset cutting parameters to obtain the first substrate after cutting; specifically, a saw blade cutting machine is used to cut the material under the conditions of a cutting speed of 4.5±0.5m / min and a cutting size tolerance of ±0.1mm; after cutting, the first substrate after cutting is drilled to obtain the first substrate after drilling; specifically, a drill bit, a pad, and an aluminum sheet are used to drill holes in a workshop environment with a temperature of 20±2°C and a drill bit grinding number of no more than 5 times, and the drilled positioning holes are used for the superposition and fixation of the first substrate and the second substrate; the first substrate after drilling is subjected to a grinding plate-lamination-exposure-development process to obtain a first substrate with an anti-corrosion protective layer, and the main parameters include: The pre-treatment grinding speed is 2.0±0.5m / min, the pickling concentration is 3%~5%, the drying temperature is 90±5℃, and the water breaking test is not less than 15s; the dry film laminating speed is 0.9±0.2m / min, the dry film laminating temperature is 120±10℃, the dry film laminating pressure is 60~80Psi, the laminating board temperature is 50±5℃, the laminating board temperature is 55±5℃, the exposure scale is 6~7 levels, the LDI exposure energy is 24.3MJ, the dust-free workshop environment is 20±2℃, the humidity is 55%±5%, the dry film developing speed is 2.5±0.5m / min, the dry film developing temperature is 30±2℃, the sodium carbonate developer concentration is 1.0%±0.2%, and the developing pressure is controlled at 60%~70% according to the developing point;

[0075] After the above treatment, an anti-corrosion protection layer reflecting the circuit outline is formed on the first substrate; then the first substrate formed with the anti-corrosion protection layer is subjected to an etching and film stripping treatment to obtain a first substrate formed with a circuit, and the specific parameters of the etching and film stripping are shown in Table 1;

[0076] Table 1 Etching stripping parameters

[0077]

[0078] After obtaining the first substrate forming the circuit, in order to prevent the first substrate and the second substrate from causing overflow, it is designed to stick an AD film on the surface of the first substrate that is bonded to the second substrate, that is, the AD film is cut according to the size of the first substrate, and then the AD film is spread on the core board, and finally the film is pressed on the core board using a laminating machine; the film sticking parameters include: the temperature of the hot pressing roller is 125±5℃, and the speed of the hot pressing roller is 3.0±0.5m / min; after sticking the AD film, the exposed position area corresponding to the second substrate design is gonged on the first substrate using a gong machine to obtain the first substrate to be pressed, wherein the parameters during gonging include: the feed speed is 10±5m / min, the travel speed is 5±2m / min, and the rotation speed is 48000~51000rpm; the workshop ambient temperature is 23±3℃, and the humidity is 60%±10%.

[0079] In an optional embodiment proposed by the present invention, step 13 may include:

[0080] Step 131, cutting the second substrate according to a second preset cutting parameter to obtain a cut second substrate;

[0081] Step 132, drilling the cut second substrate to obtain a drilled second substrate;

[0082] Step 133, grinding, laminating, exposing and developing the drilled second substrate to obtain a second substrate with an anti-corrosion protection layer;

[0083] Step 134 , performing an etching and film stripping process on the second substrate formed with the anti-corrosion protection layer to obtain a second substrate to be laminated.

[0084] In this example, the second substrate is firstly cut according to the second preset cutting parameters to obtain the second substrate after cutting; specifically, a saw blade cutting machine is used to cut the material under the conditions of a cutting speed of 4.5±0.5m / min and a cutting size tolerance of ±0.1mm; after cutting, the second substrate after cutting is drilled to obtain the second substrate after drilling; specifically, a drill bit, a pad, and an aluminum sheet are used to drill holes in a workshop environment at a temperature of 20±2°C and a drill bit grinding number of no more than 5 times, and the drilled positioning holes are used for the superposition and fixation of the first substrate and the second substrate; the second substrate after drilling is subjected to a grinding-filming-exposure-development process to obtain a second substrate with an anti-corrosion protective layer formed thereon, and the main parameters include: a pre-treatment grinding speed of 2.0±0.5m / min, a pickling concentration of 3%~5%, The drying temperature is 90±5℃, and the water breaking test is not less than 15s; the dry film laminating speed is 0.9±0.2m / min, the dry film laminating temperature is 120±10℃, the dry film laminating pressure is 60~80Psi, the film entering the board temperature is 50±5℃, the film exiting the board temperature is 55±5℃, the exposure scale is 6~7 levels, the LDI exposure energy is 24.3MJ, the dust-free workshop environment is 20±2℃, the humidity is 55%±5%, the dry film developing speed is 2.5±0.5m / min, the dry film developing temperature is 30±2℃, the sodium carbonate developer concentration is 1.0%±0.2%, and the developing pressure is controlled to be 60%~70% according to the developing point; after the above treatment, an anti-corrosion protective layer reflecting the circuit outline is formed on the second substrate; then the second substrate formed with the anti-corrosion protective layer is etched and film stripped to obtain the second substrate to be pressed. It should be noted that the method for determining the time of the etching stripping treatment here is the same as the method for determining the time of the etching stripping treatment of the first substrate mentioned above, and the etching stripping treatment time is determined according to the ambient temperature of the substrate during etching, the copper thickness of the circuit on the substrate, the line width of the actual circuit, the etching rate and the side etching effect;

[0085] In specific implementation, the copper thickness of the circuit on the substrate is usually measured in ounces, and 1oz copper thickness is about 35μm; the line width of the actual circuit refers to the actual width of the circuit width specified in the design after taking etching into account; the side etching effect refers to the phenomenon that the side of the copper layer may be etched during the etching process, which will cause the line width to become narrower;

[0086] Theoretical etching and film stripping processing time is: , where t1 is the theoretical etching time, L is the copper thickness of the circuit on the substrate, V is the etching rate, and the etching rate is a preset value;

[0087] The actual line width can be obtained according to the following formula: K = K1–2×K s , where K is the actual line width, K1 is the designed line width, and K sis the side etching amount, which is generally 10%~20% of the etching depth, and is taken as 15% in this formula;

[0088] Therefore, the actual etching and film stripping processing time can be obtained as follows:

[0089]

[0090] Among them, m T is the environmental temperature influence coefficient. Under normal circumstances, the etching temperature is in the range of 40℃~50℃. When the ambient temperature is high, the activity of the etching solution is enhanced, the etching rate is accelerated, and the etching time is shortened; when the temperature is low, the activity of the etching solution is weakened, the etching rate is slowed down, and the etching time is prolonged. Therefore, it can be set , T is the etching environment temperature.

[0091] In an optional embodiment of the present invention, step 14 may include:

[0092] Step 141, performing a browning treatment on the second substrate to be pressed to obtain a browned second substrate;

[0093] Step 142, performing a stacking and riveting process on the browned second substrate and the grooves of the first substrate to obtain a stacked and riveted substrate;

[0094] Step 143, pressing the substrate after the stacked plates are riveted together to obtain a pressed substrate with steps.

[0095] In this example, the second substrate is firstly cleaned thoroughly to remove impurities such as oil and dust on the surface, so as to ensure that the browning liquid can evenly and fully contact the surface of the substrate; the cleaned second substrate is immersed in a solution containing a browning agent; the browning agent is usually a strong oxidant, which can react chemically on the surface of the second substrate to form a rough oxide film; by controlling parameters such as the immersion time, temperature and concentration of the browning liquid, the thickness and roughness of the browning layer can be adjusted to meet the requirements of subsequent processes; after the browning treatment, the second substrate is taken out of the browning liquid, cleaned with a cleaning agent such as deionized water to remove the residual browning liquid and impurities, and then dried to obtain the browned second substrate;

[0096] The browned second substrate and the first substrate are aligned in a predetermined position and direction to ensure accurate matching between the layers; the rivets are inserted into the riveting holes and the rivets are subjected to pressure riveting by using a riveting device; during the pressure riveting process, the tail of the rivet undergoes plastic deformation, thereby being firmly fixed on the substrate; thereby the first substrate 1 with the groove position and the second substrate 2 are bonded together to form a substrate with a step difference in height; the substrates after riveting are inspected to ensure that the riveting quality meets the requirements; if necessary, the uneven or protruding parts are trimmed;

[0097] The riveted substrates are placed in a laminating machine for preheating. Preheating can remove moisture and volatile substances in the substrates and improve the laminating effect. After preheating, a certain pressure and temperature are applied to the substrates. The pressure and temperature should be adjusted according to factors such as the material, number of layers and thickness of the substrates. The adhesive between the substrates is cured by heating and pressurizing to achieve a strong bond. After applying pressure and temperature, a certain insulation time is maintained to ensure that the adhesive is fully cured. After the insulation is completed, the substrates are cooled to gradually cool to room temperature. The laminated substrates are inspected to ensure that the layers are firmly bonded and have no obvious defects. The specific parameters of the laminating process are shown in Table 2.

[0098] Table 2 Lamination process parameters

[0099]

[0100] In an optional embodiment of the present invention, step 15 may include:

[0101] Step 151, drilling the laminated substrate to obtain a drilled substrate;

[0102] Step 152, performing copper deposition treatment on the drilled substrate to obtain a copper-deposited substrate;

[0103] Step 153, performing electroplating treatment on the copper-plated substrate to obtain an electroplated substrate;

[0104] Step 154, performing copper coating etching treatment on the substrate after plate electrification to obtain a substrate after a third pretreatment.

[0105] In this example, the laminated substrate is firstly drilled to form positioning holes for mounting components on the substrate. Specifically, a drill bit, a backing plate, and an aluminum sheet are used to drill holes in a workshop environment at a temperature of 20±2°C and the drill bit is ground no more than 5 times.

[0106] The substrate after drilling is subjected to copper deposition treatment, that is, a layer of metal copper is deposited on the surface of the hole or the substrate position of the board surface by chemical means, so as to provide base copper for subsequent electroplating to increase the copper thickness, and finally achieve the conductivity and heat dissipation required by the product; the steps of copper deposition treatment include: board loading - swelling - water washing - degumming - recycling - water washing - pre-neutralization - high-level water washing - neutralization - water washing - degreasing - hot water washing - water washing - micro-etching - water washing - pre-impregnation - activation - water washing - speeding up - water washing - copper deposition - water washing - board loading;

[0107] The substrate after copper deposition is subjected to board electrical treatment to increase the thickness of the copper deposition layer; the steps of board electrical treatment include: board loading - pickling - double water washing - pre-impregnation - copper plating - double water washing - board lowering - peeling - water washing - chuck brush drying - board lowering;

[0108] The substrate after the board is electroplated is subjected to copper coating etching treatment, which specifically includes: firstly, grinding the board - laminating - exposure - development treatment, forming an anti-corrosion protection layer on the substrate, exposing the unnecessary copper layer position, and protecting the necessary copper layer position, and removing the unnecessary copper layer by chemical micro-etching, leaving the necessary copper layer position; the micro-etching steps include placing the board on the horizontal line - water washing - micro-etching - water washing - strong wind drying, and the main parameters of micro-etching include micro-etching speed of 1.1m / min, micro-etching solution temperature of 35±5℃, sulfuric acid concentration of 150~200g / L, and hydrogen peroxide concentration of 40~80ml / L;

[0109] After the substrate is micro-etched, the anti-corrosion dry film (i.e., anti-corrosion protective layer) needs to be removed to expose the required copper layer; the film removal steps include placing the board on the horizontal line - film removal - water washing - strong wind drying - high temperature drying; the main parameters include micro-etching speed of 2.5m / min, film removal liquid temperature of 40±5℃, and film removal liquid concentration of 5±2% sodium hydroxide;

[0110] After the film is stripped, the substrate is then subjected to graphic circuit processing and graphic electroplating processing in sequence, that is, an anti-corrosion protective layer is formed on the substrate by an exposure-development method to expose the unnecessary copper layer position and protect the necessary copper layer position, and then the copper layer thickness on the hole wall and the substrate is increased by electroplating, and then etching is performed again. The unnecessary copper layer is cleaned by chemical methods, leaving the required graphic circuit copper layer, and finally the substrate after the third pretreatment is obtained.

[0111] In an optional embodiment of the present invention, step 16 may include:

[0112] Step 161, optically inspecting the substrate after the third pretreatment to obtain a substrate after the optical inspection;

[0113] Step 162, performing solder mask text processing on the substrate after the optical inspection to obtain a substrate after the solder mask text processing;

[0114] Step 163, performing surface gold deposition on the substrate after the solder mask text processing to obtain a substrate after the surface gold deposition;

[0115] Step 164, cutting and shaping the substrate after the surface immersion gold treatment to obtain a high-precision step circuit board.

[0116] In this example, the production board is first optically inspected, and the image of the production board is collected. The image is then checked against the design data to check whether there are PCB defects such as line gaps, line open circuits, thin lines, thick lines, etc. on the production board; then the substrate after the electroplating and etching treatment is subjected to solder mask text processing to obtain a substrate after solder mask text processing; wherein the main materials for solder mask processing include solder mask ink, oil-opening water, industrial sodium carbonate and industrial sulfuric acid, and the main parameters include a pre-treatment grinding speed of 1.5±0.5m / min, a pickling concentration of 3%~5%, a drying temperature of 90±5°C, and a printing speed of 1.5±0.5m / min; the main materials for text processing include character ink and inkjet cleaning fluid; the substrate after the solder mask text processing is subjected to Surface immersion gold treatment is performed to obtain a substrate after surface immersion gold treatment; wherein, the main materials for surface treatment include gold salt, activation, pre-immersion and sulfuric acid; the main parameters include degreasing temperature of 40~60℃, degreasing concentration of 20~120ml / L, sodium persulfate of 80~13g / L, sulfuric acid of 10~30ml / L, micro-etching temperature of 28~32℃, activation temperature of 25~30℃, activation concentration of 80~120ml / L, chemical nickel temperature of 79~81℃, nickel bath concentration of 4.3~4.6g / L, bath load of 0.3~1.0d㎡ / L, PH of 4.5~4.7, immersion gold plating temperature of 85~90℃, PH of 4.8~6.0, gold concentration of 0.5~1.2%, and gold liquid concentration of 100ml / L.

[0117] A specific embodiment of the method for manufacturing a high-precision stepped circuit board provided by an embodiment of the present invention is:

[0118] Step 1, providing a first substrate and a second substrate;

[0119] First, prepare two substrates, namely a first substrate and a second substrate, both of which are made of epoxy boards (FR-4);

[0120] Step 2, performing a first pretreatment on the first substrate to obtain a first substrate to be pressed;

[0121] Specifically, a saw blade cutting machine is used to cut the material at a cutting speed of 4.5±0.5m / min and a cutting size tolerance of ±0.1mm; after cutting, a positioning hole is drilled for the first substrate after cutting using a drill bit, a pad, and an aluminum sheet in a workshop environment at a temperature of 20±2°C and the drill bit is ground no more than 5 times, and the positioning hole is used for precise positioning and fixing when the first substrate and the second substrate are superimposed; the first substrate after drilling is subjected to a grinding-film pressing-exposure-development process to form an anti-corrosion protective layer reflecting the outline of the circuit on the first substrate; then the first substrate formed with the anti-corrosion protective layer is subjected to an etching and film stripping process to obtain a first substrate formed with a circuit; in order to prevent the first substrate and the second substrate from causing a poor overflow of glue when they are combined, an AD film is designed to be pasted on the surface of the first substrate that is bonded to the second substrate; after pasting the AD film, a gong machine is used to gong the exposed position area corresponding to the second substrate design on the first substrate to obtain the first substrate to be pressed;

[0122] Step 3, performing a second pretreatment on the second substrate to obtain a second substrate to be pressed;

[0123] Specifically, a saw blade cutting machine is used to cut the material under the conditions of a cutting speed of 4.5±0.5m / min and a cutting size tolerance of ±0.1mm; after cutting, a positioning hole is drilled on the second substrate after cutting using a drill bit, a pad, and an aluminum sheet in a workshop environment at a temperature of 20±2°C and the drill bit is ground no more than 5 times, and the positioning hole is used for precise positioning and fixing when the first substrate and the second substrate are superimposed; the second substrate after drilling is subjected to a grinding-filming-exposure-development process to form an anti-corrosion protective layer reflecting the circuit contour on the second substrate; and then the second substrate formed with the anti-corrosion protective layer is subjected to an etching and film stripping process to obtain a second substrate to be pressed;

[0124] Step 4, performing a lamination process on the first substrate to be laminated and the second substrate to be laminated to obtain laminated substrates;

[0125] Specifically, firstly, the second substrate is thoroughly cleaned to remove impurities such as oil and dust on the surface; the cleaned second substrate is immersed in a solution containing a browning agent for browning treatment, then the second substrate is taken out of the browning liquid, cleaned with a cleaning agent such as deionized water to remove the residual browning liquid and impurities, and then dried to obtain the browned second substrate; the browned second substrate and the first substrate are aligned according to a predetermined position and direction to ensure accurate matching between the layers; the rivets are inserted into the riveting holes, and the rivets are press-riveted using a riveting device; the substrates after riveting the stacked plates are placed in a pressing machine for preheating treatment; after preheating, a certain pressure and temperature are applied to the substrates to cause the adhesive between the substrates to undergo a curing reaction, thereby achieving a firm bond.

[0126] Step 5, performing a third pretreatment on the laminated substrate to obtain a substrate after the third pretreatment;

[0127] Specifically, the laminated substrate is firstly subjected to drilling treatment to form positioning holes for mounting components on the substrate; the drilled substrate is subjected to copper plating treatment to deposit a layer of metal copper on the surface of the hole or the substrate position of the board surface by chemical means to provide base copper for subsequent electroplating to increase the copper thickness; the copper plating substrate is then subjected to plate electroplating treatment to increase the thickness of the copper plating layer; the plate electroplating substrate is subjected to copper coating etching treatment, including: firstly, plate grinding-film lamination-exposure-development treatment is performed to form an anti-corrosion protective layer on the substrate, which will expose the unnecessary copper layer position and protect the necessary copper layer position, and the unnecessary copper layer is removed by chemical micro-etching. Clean it and leave the required copper layer position; after the substrate is micro-etched, the anti-corrosion dry film (i.e., anti-corrosion protective layer) needs to be removed to expose the required copper layer; the substrate after film removal is then subjected to graphic circuit processing and graphic electroplating processing in sequence, that is, through the exposure-development method, an anti-corrosion protective layer is formed on the substrate to expose the unnecessary copper layer position and protect the necessary copper layer position, and then the copper layer thickness on the hole wall and the substrate is increased by electroplating, and then etching is performed again, and the unnecessary copper layer is cleaned by chemical means, leaving the required graphic circuit copper layer, and finally the substrate after the third pretreatment is obtained.

[0128] Step 6, performing molding processing on the substrate after the third pretreatment to obtain a high-precision step circuit board.

[0129] Specifically, firstly, the production board is optically inspected to check whether there are any defects on the production board; then, the substrate after the electroplating and etching treatment is subjected to solder mask text treatment to obtain a substrate after solder mask text treatment, wherein the solder mask layer is usually a special ink or resin material, which is used to protect the non-conductive area of ​​the circuit board to prevent short circuit or damage during the subsequent welding process; after the solder mask layer is dried and cured, text printing is performed; the text printing usually includes the logo, component number, polarity mark, etc. on the circuit board, which is used to guide the subsequent assembly and testing; the substrate after the solder mask text treatment is subjected to surface gold plating treatment to obtain a substrate after surface gold plating, wherein gold plating is a chemical gold plating method, which deposits a thin layer of gold on the surface of the substrate through a chemical reaction; this layer of gold not only has good conductivity and corrosion resistance, but also provides an aesthetic appearance; after the gold plating is completed, post-processing is performed, including steps such as cleaning and drying to remove all residues and ensure the firm adhesion of the gold layer; a laser cutting machine, a mechanical punch or a water jet and other equipment are used to cut and shape the substrate according to the cutting procedure to obtain a high-precision step circuit board.

[0130] The above-mentioned technical scheme of the present invention realizes the efficient production of high-precision step circuit boards and improves the product performance quality by first making the circuit boards in layers and then performing pressing and molding processes.

[0131] In an optional embodiment of the present invention, the method further comprises the following steps:

[0132] Step 171, testing and inspecting the high-precision step circuit board according to preset test conditions to obtain a qualified high-precision step circuit board; the preset test conditions include at least one of the following conditions:

[0133] Step 172, open circuit and short circuit test conditions, test voltage is 20~500V, test current is 5~200mA, conduction test range is 2~10000ohm, insulation test range is 5~500Mohm, equivalent test range is 0.1pF~10mF, and ambient temperature is 22℃~26℃.

[0134] In this embodiment, in order to improve the qualified rate of circuit boards and user satisfaction, it is necessary to inspect the high-precision step circuit boards. Only circuit boards that pass the preset inspection conditions are qualified high-precision step circuit boards and can be used for subsequent production or shipment. In this embodiment, after the high-precision step circuit boards are inspected according to the above inspection method, the qualified rate of high-precision step circuit boards is high, which fully meets the market demand.

[0135] like Figure 2 As shown, an embodiment of the present invention proposes a high-precision step circuit board, which is prepared by the method for making a high-precision step circuit board according to any one of the above embodiments. The high-precision step circuit board comprises: a first substrate 1, a second substrate 2, a first circuit layer 3, a second circuit layer 6, and a via 4, wherein the first substrate 1 and the second substrate 2 are bonded together by an AD adhesive film layer 5, and at the same time, the first substrate 1 has a gong groove, and the first substrate 1 with the gong groove is bonded with the second substrate 2 to form a substrate with a step having a step difference in height.

[0136] The above are preferred embodiments of the present invention. It should be pointed out that, for ordinary technicians in this technical field, several improvements and modifications can be made without departing from the principles of the present invention. These improvements and modifications should also be regarded as within the scope of protection of the present invention.

Claims

1. A method for manufacturing a high-precision step circuit board, characterized in that: include: providing a first substrate and a second substrate; Performing a first pretreatment on the first substrate to obtain a first substrate to be pressed, wherein the first substrate has a groove position; Performing a second pretreatment on the second substrate to obtain a second substrate to be pressed; Performing a lamination process on the first substrate to be laminarized and the second substrate to be laminarized to obtain a laminar substrate with a step, wherein the gong groove is in contact with the second substrate; Performing a third pretreatment on the laminated substrate with steps to obtain a substrate after the third pretreatment; The substrate after the third pretreatment is subjected to a molding process to obtain a high-precision step circuit board.

2. The method for manufacturing a high-precision stepped circuit board according to claim 1, characterized in that: Performing a first pretreatment on the first substrate to obtain a first substrate to be pressed, comprising: Cutting the first substrate according to first preset cutting parameters to obtain a cut first substrate; Performing a drilling process on the cut first substrate to obtain a drilled first substrate; The first substrate after drilling is subjected to grinding, lamination, exposure and development processes to obtain a first substrate with an anti-corrosion protection layer; Performing an etching and film stripping process on the first substrate formed with the anti-corrosion protection layer to obtain a first substrate formed with circuits; Performing adhesive film treatment on the first substrate on which the circuit is formed to obtain a first substrate with an adhesive film; The first substrate with the adhesive film is subjected to a groove opening process to obtain a first substrate to be pressed.

3. The method for manufacturing a high-precision stepped circuit board according to claim 1, characterized in that: Performing a second pretreatment on the second substrate to obtain a second substrate to be pressed, comprising: Cutting the second substrate according to second preset cutting parameters to obtain a cut second substrate; Performing a drilling process on the cut second substrate to obtain a drilled second substrate; The drilled second substrate is subjected to grinding, lamination, exposure and development processes to obtain a second substrate with an anti-corrosion protection layer; The second substrate with the anti-corrosion protection layer formed thereon is subjected to an etching and film stripping treatment to obtain a second substrate to be laminated.

4. The method for manufacturing a high-precision stepped circuit board according to claim 1, characterized in that: The first substrate to be pressed and the second substrate to be pressed are pressed together to obtain a pressed substrate with steps, comprising: Performing a browning treatment on the second substrate to be pressed to obtain a browned second substrate; Performing a stacking and riveting process on the browned second substrate and the grooves of the first substrate to obtain a stacked and riveted substrate; The substrate after the stacked plates are riveted is pressed to obtain a pressed substrate with steps.

5. The method for manufacturing a high-precision stepped circuit board according to claim 1, characterized in that: Performing a third pretreatment on the laminated substrate with steps to obtain a substrate after the third pretreatment, comprising: Performing drilling processing on the pressed substrate to obtain a drilled substrate; Performing copper deposition on the drilled substrate to obtain a copper-deposited substrate; Performing electroplating treatment on the copper-plated substrate to obtain an electroplated substrate; The substrate after the plate electroplating is subjected to a copper coating etching process to obtain a substrate after the third pretreatment.

6. The method for manufacturing a high-precision stepped circuit board according to claim 5, characterized in that: The substrate after the plate is subjected to copper coating etching treatment to obtain a substrate after the third pretreatment, comprising: The substrate after electroplating is subjected to grinding, lamination, exposure and development processes to obtain a substrate with an anti-corrosion protection layer; Performing micro-etching treatment on the substrate formed with the anti-corrosion protection layer to obtain a substrate formed with circuits; Performing a film stripping process on the substrate on which the circuit is formed to obtain a film stripped substrate; The substrate after film stripping is subjected to electroplating and etching treatment to obtain a substrate after the third pretreatment.

7. The method for manufacturing a high-precision stepped circuit board according to claim 6, characterized in that: The substrate after the film stripping is subjected to electroplating and etching treatment to obtain a substrate after the third pretreatment, comprising: The substrate after the film stripping is subjected to grinding, lamination, exposure and development treatments to obtain a substrate with an anti-corrosion protective layer; Performing pattern electroplating on the substrate formed with the anti-corrosion protection layer to obtain a pattern electroplated substrate; The substrate after pattern electroplating is etched to obtain a substrate after a third pretreatment.

8. The method for manufacturing a high-precision stepped circuit board according to claim 1, characterized in that: The substrate after the third pretreatment is subjected to a molding process to obtain a high-precision step circuit board, comprising: performing optical inspection on the substrate after the third pretreatment to obtain a substrate after optical inspection; Performing solder mask text processing on the substrate after the optical inspection to obtain a substrate after the solder mask text processing; Performing surface gold immersion treatment on the substrate after the solder mask text processing to obtain a substrate after the surface gold immersion treatment; The substrate with the surface immersion gold is cut and formed to obtain a high-precision step circuit board.

9. The method for manufacturing a high-precision stepped circuit board according to claim 1, characterized in that: Also includes: The high-precision step circuit board is tested and inspected according to preset test conditions to obtain a qualified high-precision step circuit board; the preset test conditions include at least one of the following conditions: Open circuit and short circuit test conditions, test voltage is 20~500V, test current is 5~200mA, continuity test range is 2~10000ohm, insulation test range is 5~500Mohm, equivalent test range is 0.1pF~10mF, ambient temperature is 22℃~26℃.

10. A high-precision step circuit board, characterized in that: The high-precision step circuit board is prepared by the method described in any one of claims 1 to 9.

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