A method for manufacturing a microwave plate with tiny blind slots

Abstract

A method for fabricating a microwave board with small blind slots includes the following steps: STEP 101: Fabrication of L1 / L2 layer: blanking → inner layer drilling → milling of adhesive positioning frame → inner layer pretreatment → inner layer lamination → inner layer exposure → inner layer development → inner layer inspection → inner layer acid etching → inner layer stripping → inner layer AO I → browning → transfer bonding of outer layer fabrication; STEP 102: Fabrication of L3 / L4 layer; STEP 103: Fabrication of L5 / L6 layer: blanking → inner layer drilling → milling of adhesive positioning frame → inner layer pretreatment → inner layer lamination → inner layer exposure → inner layer development → inner layer inspection → inner layer acid etching → inner layer stripping → inner layer AO I → inner layer AO I → Browning → Transfer and lamination of outer layer fabrication; STEP 104: Fabrication of L7 / L8 layer; STEP 105: Lamination of L1 to L4 layers; STEP 106: Lamination of L5 to L8 layers; STEP 107: Fabrication of PP; STEP 108: Lamination of L1 to L8 to complete the fabrication of microwave board with small blind slots. The microwave board with small blind slots is thus fabricated at a lower cost and with a guaranteed yield.

Description

Technical Field

[0001] This invention relates to the field of circuit board manufacturing technology, and in particular to a method for manufacturing a microwave board with tiny blind slots. Background Technology

[0002] In the electronics industry, circuit boards have become an indispensable component. The primary function of a conventional PCB is to form the conductors that transmit information. However, with the rapid development of the electronics industry, the demand for circuit boards is increasing, and the requirements and corresponding functions for these boards are also becoming more diverse. Therefore, circuit board designs are becoming more complex and integrated, with a large number of components integrated onto the board to achieve various functions.

[0003] However, with the large-scale integration of components onto circuit boards, the space on these boards has become extremely congested. To expand the mounting space, blind slots, also known as power amplifier slots, are typically created on the circuit board, and components are then installed within these slots to alleviate congestion. As is well known, blind slots are used for soldering and fixing electronic components, and their size, depth, and shape are subject to strict requirements. Currently, blind slots are typically 5*5mm square slots. However, with the increasing density of electronic devices, their growing functionality, and miniaturization, for some power amplifier-based high-frequency communication products, the blind slots will house power amplifier components, leading to increasingly higher dimensional accuracy requirements. Designing smaller blind slots, however, can result in issues such as adhesive residue and deformation. Furthermore, the rapid development of communication technology has led to increasingly higher demands on product performance and integration, making the manufacturing of circuit boards with such high-precision blind slots increasingly difficult. Therefore, designing a reasonable method for manufacturing small blind slot microwave boards is crucial for reducing costs and improving yield. Summary of the Invention

[0004] In view of this, the present invention provides a method for manufacturing a microwave plate with tiny blind slots that can solve the above-mentioned technical problems.

[0005] A method for manufacturing a microwave plate with tiny blind slots includes the following steps:

[0006] STEP101: Fabrication of L1 / L2 layers: Material cutting → Inner layer drilling → Milling of adhesive positioning frame → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Browning → Transfer lamination of outer layer fabrication.

[0007] STEP102: Fabrication of L3 / L4 layers: Material cutting → Copper reduction of substrate → Laser cutting of tape → Inner layer drilling → Finished product cleaning machine → Hole inspection → Plasma → Chemical copper (PTH) → Electroplating of copper → Plasma → Chemical copper → Copper thickening → Circuit inspection → Resin plugging → Resin grinding → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Lamination before gold plating → Exposure before gold plating → Development before gold plating → Hard gold plating → Stripping after gold plating → Lamination after inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Etching of gold plating wires → Inner layer AO I → Measure the expansion and contraction coefficient of layers 3-4, and obtain the expansion and contraction data of the remaining layers → Pressing and baking → Applying tape.

[0008] STEP103: Fabrication of L5 / L6 layer: Material cutting → Inner layer drilling → Milling of adhesive positioning frame → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Browning → Transfer lamination of outer layer fabrication.

[0009] STEP104: Fabrication of L7 / L8 layer: Material cutting → Inner layer drilling → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Lamination before gold plating → Exposure before gold plating → Development before gold plating → Electroplating hard gold → Stripping after gold plating → Lamination and baking → Applying tape → Lamination of outer layer.

[0010] STEP105: Lamination of L1 to L4 layers: Lamination → Milling → Measurement → Inner layer drilling → Finished product cleaning machine → Hole inspection → Plasma → Chemical copper → Electroplating of copper → Plasma → Chemical copper → Copper thickening → Circuit inspection → Resin plugging → Resin grinding → Drilling → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Browning → Transfer lamination to outer layer fabrication;

[0011] STEP106: Lamination of L5 to L8 layers: Lamination → Milling → Measurement → Inner layer drilling → Finished product cleaning machine → Hole inspection → Milling of adhesive positioning frame → Plasma → Chemical copper → Electroplating of copper → Plasma → Chemical copper → Copper thickening → Circuit inspection → Resin plugging → Resin grinding → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Lamination before gold plating → Exposure before gold plating → Development before gold plating → Hard gold plating → Stripping after gold plating → Lamination after inner layer lamination → Exposure before inner layer exposure → Development → Inner layer inspection → Etching of gold plating wires → Stripping of inner layer → Inner layer AO I → Browning → Applying adhesive tape → Transfer lamination of outer layer fabrication.

[0012] STEP107: PP fabrication: lamination → PP drilling → PP milling → outer layer fabrication;

[0013] STEP108: Lamination L1 to L8: Lamination → Drilling → Small board cleaning → Hole inspection → First ion → Chemical copper → Electroplating copper → Outer layer lamination → Outer layer exposure → Outer layer development → Circuit inspection → Pattern electroplating → Outer layer stripping → Outer layer alkaline etching → Outer layer tin stripping → Outer layer AO I → Chemical gold EN IG → Text → Long copy → Second drilling → First deep milling of blind slot → Second deep milling of blind slot → Third deep milling of blind slot → Milling → Finished product testing → FQC inspection → Packaging → FQA inspection → Completion of the small blind slot microwave board.

[0014] Furthermore, in STEP101, during the inner layer pretreatment, the board is not brushed. During the inner layer exposure, the GTL layer is used as an auxiliary layer for full-surface exposure. The L2 layer is produced using the measured expansion and contraction file for the smooth surface. During the inner layer acid etching, the L2 layer is etched into a smooth surface.

[0015] Furthermore, in STEP102, the copper reduction of the substrate is micro-etched to 8-12 μm. When laser-cutting the tape, the tape thickness is 0.1 mm. During resin plugging, vacuum plugging is used, employing high-frequency PTFE material. During resin grinding, the material is ground to 17-23 μm. During inner layer exposure, the exposure equipment is LDI, with a minimum front-side linewidth of 17.7 μm and a minimum front-side pitch of 16.5 μm. During inner layer acid etching, the etching tolerance is + / - 0.8 μm, the minimum linewidth is 14.2 μm, and the minimum pitch is 20 μm. During hard gold plating, the GTL nickel thickness is 4-7 μm, the GTL gold thickness is ≥0.05 μm, and the GTL hard gold plating area is 0.162 d / m². 2 .

[0016] Furthermore, in STEP103, during the inner layer exposure, the L5 layer is exposed as an auxiliary layer, and the L6 layer is a smooth surface produced using the measured expansion and contraction data. During the inner layer acid etching, the L6 layer is etched into a smooth surface.

[0017] Furthermore, in STEP104, during the inner layer exposure, when fabricating the L7 layer circuit, the GBL layer serves as an auxiliary layer. The retained copper foil is produced based on the measured expansion and contraction data. The exposure equipment is an LDI, with a minimum line width of 17.2 μm and a minimum pitch of 16.5 μm for the front film. During the inner layer acid etching, the etching tolerance is + / - 0.8 μm, the minimum line width is 13.8 μm, and the minimum pitch is 20 μm. During the exposure before gold plating, L7 serves as an auxiliary layer, and the entire GBL layer is exposed as a positive film.

[0018] Furthermore, in STEP105, after laminating layers L1 to L4, the thickness tolerance of the laminated board is 1.15 mm. During resin via plugging, vacuum plugging is used, and the plugging material is high-frequency PTFE. During inner layer exposure, the exposure equipment is an LD Im film with a minimum linewidth of 23.5 μm and a minimum pitch of 16.5 μm. The L4 layer circuitry is fabricated, and the GTL layer serves as an auxiliary layer, retaining the copper foil. During inner layer acid etching, the etching tolerance is + / - 0.8 μm, the minimum linewidth after reverse etching is 20 μm, and the minimum pitch after reverse etching is 20 μm.

[0019] Furthermore, in STEP108, after laminating L1 to L8, the thickness of the laminated plate is 2.4728 mm. During outer layer lamination, high-temperature tape should be applied first, followed by lamination. For outer layer exposure, the exposure equipment is LDI, with a minimum line width of 22 μm for the front film and a minimum pitch of 18 μm for the front film. The minimum line width for the reverse film is 17.7 μm, and the minimum pitch for the reverse film is 18 mil. During pattern electroplating, the GTL plating area is 10.25 μm, the GBL plating area is 8.64 μm, and the completed hole copper thickness is 30 μm. High-temperature tape should be applied first, followed by electroplating. During outer layer alkaline etching, the etching tolerance is + / - 0.8 μm, with a minimum line width of 20 μm for the front etching and a minimum pitch of 20 μm for the front etching. The minimum line width for the reverse etching is 15.7 μm, and the minimum pitch for the reverse etching is 20 mil. In the chemical gold EN... During IG (In-Glass Injection), the GTL nickel thickness is 3-5µm, the GBL nickel thickness is 3-5µm, the GTL gold thickness is ≥0.05µm, the GBL gold thickness is ≥0.05µm, the GTL gold plating area is 30%, and the GBL gold plating area is 48%. High-temperature tape is applied first, and then the gold plating is carried out externally.

[0020] Furthermore, when slotting or drilling, PI tape of the same dielectric layer thickness is used to protect the slotted areas of layers L3, L4, and L7 to prevent scratches on the gold surface and reduce foot marks.

[0021] Furthermore, during the grooving process, when the distance between the edges of the blind groove is ≥5mm, the electroplated area of ​​the circuit is extended 1.02mm into the blind groove to prevent uneven copper thickness at the edge of the blind groove and to ensure that the non-conductive copper foil or circuit is covered by a dry film.

[0022] Furthermore, when slotting, if the distance between blind slot edges is less than 5mm, the copper area should be appropriately reduced to avoid delamination after lamination.

[0023] Compared with the prior art, the method for manufacturing a microwave board with small blind slots provided by the present invention includes the following steps: STEP 101: Manufacturing L1 / L2 layer: blanking → inner layer drilling → milling adhesive positioning frame → inner layer pretreatment → inner layer lamination → inner layer exposure → inner layer development → inner layer inspection → inner layer acid etching → inner layer film removal → inner layer AO I → browning → transfer bonding to outer layer manufacturing; STEP 102: Manufacturing L3 / L4 layer: blanking → substrate copper reduction → laser cutting tape → inner layer drilling → finished product cleaning machine → hole inspection → plasma → chemical copper (PTH) → electroplating copper → plasma; STEP 103: Manufacturing L5 / L6 layer: blanking → inner layer drilling → milling adhesive positioning frame → inner layer pretreatment → inner layer lamination → inner layer exposure → inner layer development → inner layer inspection → inner layer acid etching → inner layer film removal → inner layer AO I → browning → transfer bonding to outer layer manufacturing; I → Browning → Transfer lamination of outer layer fabrication; STEP 104: Fabrication of L7 / L8 layer: Material cutting → Inner layer drilling → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Pre-gold plating lamination → Pre-gold plating exposure → Pre-gold plating development → Electroplating hard gold → Post-gold plating stripping → Lamination and baking → Applying tape → Transfer lamination of outer layer fabrication; STEP 105: Lamination of L1 to L4 layers: Lamination → Milling → Measurement → Inner layer drilling → Finished product cleaning machine → Hole inspection → Plasma → Chemical copper → Electroplating copper → Plasma → Chemical copper → Copper thickening → Circuit inspection → Resin plugging → Resin grinding → Drilling → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Browning → Transfer lamination of outer layer fabrication; STEP 106: Lamination of L5 to L8 layers; STEP 107: Fabrication of PP; STEP 108: Lamination of L1 to L8: Lamination → Drilling → Small board cleaning → Hole inspection → First ion → Chemical copper → Electroplating of copper → Outer layer lamination → Outer layer exposure → Outer layer development → Circuit inspection → Pattern electroplating → Outer layer stripping → Outer layer alkaline etching → Outer layer tin stripping → Outer layer AO I → Chemical gold EN IG → Text → Long copy → Second drilling → First deep milling of blind groove → Second deep milling of blind groove → Third deep milling of blind groove → Milling → Finished product testing → FQC inspection → Packaging → FQA inspection → Completion of the fabrication of microwave board with fine blind grooves. The microwave board with fine blind grooves produced in this way not only has a lower cost, but also ensures a high yield. Detailed Implementation

[0024] The following provides a more detailed description of specific embodiments of the present invention. It should be understood that the description of the embodiments of the present invention herein is not intended to limit the scope of protection of the present invention.

[0025] The present invention provides a method for manufacturing a microwave plate with tiny blind slots, comprising the following steps:

[0026] STEP101: Fabrication of L1 / L2 layers: Material cutting → Inner layer drilling → Milling of adhesive positioning frame → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Browning → Transfer lamination of outer layer fabrication.

[0027] STEP102: Fabrication of L3 / L4 layers: Material cutting → Copper reduction of substrate → Laser cutting of tape → Inner layer drilling → Finished product cleaning machine → Hole inspection → Plasma → Chemical copper (PTH) → Electroplating of copper → Plasma → Chemical copper → Copper thickening → Circuit inspection → Resin plugging → Resin grinding → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Lamination before gold plating → Exposure before gold plating → Development before gold plating → Hard gold plating → Stripping after gold plating → Lamination after inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Etching of gold plating wires → Inner layer AO I → Measure the expansion and contraction coefficient of layers 3-4, and obtain the expansion and contraction data of the remaining layers → Pressing and baking → Applying tape.

[0028] STEP103: Fabrication of L5 / L6 layer: Material cutting → Inner layer drilling → Milling of adhesive positioning frame → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Browning → Transfer lamination of outer layer fabrication.

[0029] STEP104: Fabrication of L7 / L8 layer: Material cutting → Inner layer drilling → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Lamination before gold plating → Exposure before gold plating → Development before gold plating → Electroplating hard gold → Stripping after gold plating → Lamination and baking → Applying tape → Lamination of outer layer.

[0030] STEP105: Lamination of L1 to L4 layers: Lamination → Milling → Measurement → Inner layer drilling → Finished product cleaning machine → Hole inspection → Plasma → Chemical copper → Electroplating of copper → Plasma → Chemical copper → Copper thickening → Circuit inspection → Resin plugging → Resin grinding → Drilling → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Browning → Transfer lamination to outer layer fabrication;

[0031] STEP106: Lamination of L5 to L8 layers: Lamination → Milling → Measurement → Inner layer drilling → Finished product cleaning machine → Hole inspection → Milling of adhesive positioning frame → Plasma → Chemical copper → Electroplating of copper → Plasma → Chemical copper → Copper thickening → Circuit inspection → Resin plugging → Resin grinding → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Lamination before gold plating → Exposure before gold plating → Development before gold plating → Hard gold plating → Stripping after gold plating → Lamination after inner layer lamination → Exposure before inner layer exposure → Development → Inner layer inspection → Etching of gold plating wires → Stripping of inner layer → Inner layer AO I → Browning → Applying adhesive tape → Transfer lamination of outer layer fabrication.

[0032] STEP107: PP fabrication: lamination → PP drilling → PP milling → outer layer fabrication;

[0033] STEP108: Lamination L1 to L8: Lamination → Drilling → Small board cleaning → Hole inspection → First ion → Chemical copper → Electroplating copper → Outer layer lamination → Outer layer exposure → Outer layer development → Circuit inspection → Pattern electroplating → Outer layer stripping → Outer layer alkaline etching → Outer layer tin stripping → Outer layer AO I → Chemical gold EN IG → Text → Long copy → Second drilling → First deep milling of blind slot → Second deep milling of blind slot → Third deep milling of blind slot → Milling → Finished product testing → FQC inspection → Packaging → FQA inspection → Completion of the small blind slot microwave board.

[0034] In STEP101, do not brush the board during inner layer pretreatment. During inner layer exposure, the GTL layer is used as an auxiliary layer for full-area exposure, and L2 is produced using measured expansion and contraction data for a smooth finish. During inner layer etching, the L2 layer is etched to a smooth finish.

[0035] In STEP 102, the copper reduction process on the substrate is micro-etched to 8-12 μm. The tape thickness is 0.1 mm during laser cutting. For resin plugging, vacuum plugging is used, employing high-frequency PTFE material. During resin polishing, the thickness is reduced to 17-23 μm. For inner layer exposure, an LDI exposure device is used, with a minimum front-side linewidth of 17.7 μm and a minimum front-side pitch of 16.5 μm. During inner layer acid etching, the etching tolerance is + / - 0.8 μm, the minimum linewidth is 14.2 μm, and the minimum pitch is 20 μm. For hard gold plating, the GTL nickel thickness is 4-7 μm, the GTL gold thickness is ≥0.05 μm, and the GTL hard gold plating area is 0.162 d / m². 2 .

[0036] In STEP 103, during inner layer exposure, layer L5 is exposed as an auxiliary layer across the entire surface, while layer L6 is a smooth layer produced using measured expansion and contraction data. During inner layer etching, layer L6 is etched to a smooth finish.

[0037] In STEP 104, during the inner layer exposure, when fabricating the L7 layer circuitry, the GBL layer serves as an auxiliary layer, and the retained copper foil is produced based on measured expansion and contraction data. The exposure equipment is an LDI, with a minimum front-side film linewidth of 17.2 μm and a minimum front-side film pitch of 16.5 μm. During the inner layer acid etching, the etching tolerance is + / - 0.8 μm, the minimum linewidth is 13.8 μm, and the minimum pitch is 20 μm. During the pre-gold plating exposure, L7 serves as an auxiliary layer, and the entire GBL layer is exposed as a positive film.

[0038] In STEP105, after laminating layers L1 to L4, the thickness tolerance of the laminated board is 1.15 mm. For resin via plugging, vacuum plugging is used, and the plugging material is high-frequency PTFE. During inner layer exposure, the exposure equipment is an LD 1m reverse film with a minimum linewidth of 23.5 μm and a minimum pitch of 16.5 μm. The L4 layer circuitry is fabricated, and the GTL layer is used as an auxiliary layer to retain the copper layer. During inner layer acid etching, the etching tolerance is + / - 0.8 μm, the minimum linewidth after reverse etching is 20 μm, and the minimum pitch after reverse etching is 20 μm.

[0039] In STEP106, the thickness tolerance of the laminated plate after lamination of layers L5 to L8 is 1.15 mm. During edge milling, the outer frame is milled and smoothed using a forming machine. For inner layer exposure, the exposure equipment is LDI, with a minimum front film linewidth of 19.2 mil and a minimum front film pitch of 16.5 mil. When fabricating the L5 layer circuitry, the GTL layer is used as an auxiliary layer for full-area exposure. During inner layer acid etching, the etching tolerance is + / - 0.8 mil, the minimum linewidth after front etching is 15.7 mil, and the minimum pitch after front etching is 20 mil. Before gold plating, the L5 layer is used as an auxiliary layer, and the BGL layer is fully exposed as a positive film. During hard gold plating, the GTL nickel thickness is 4-7 μm, the GTL gold thickness is ≥0.05 μm, and the GTL hard gold plating area is 2.5867 d / m². 2 .

[0040] In STEP107, when making PP, the PP is first cut and then pressed together.

[0041] In STEP108, after laminating L1 to L8, the thickness of the laminated plate is 2.4728 mm. During outer layer lamination, high-temperature tape should be applied first, followed by lamination. For outer layer exposure, the exposure equipment is LDI, with a minimum linewidth of 22 μm for the front film and a minimum pitch of 18 μm for the front film; a minimum linewidth of 17.7 μm for the reverse film; and a minimum pitch of 18 μm for the reverse film. During pattern electroplating, the GTL plating area is 10.25 μm, the GBL plating area is 8.64 μm, and the completed hole copper thickness is 30 μm. High-temperature tape should be applied first, followed by electroplating. During outer layer alkaline etching, the etching tolerance is + / - 0.8 μm, with a minimum linewidth of 20 μm and a minimum pitch of 20 μm for the front etching; a minimum linewidth of 15.7 μm for the reverse etching; and a minimum pitch of 20 μm for the reverse etching. During the electroless gold EN IG process, the GTL nickel thickness is 3-5µm, the GBL nickel thickness is 3-5µm, the GTL gold thickness is ≥0.05µm, the GBL gold thickness is ≥0.05µm, the GTL electroless gold area is 30%, and the GBL electroless gold area is 48%. High-temperature tape is applied first, and then the electroless gold process is carried out externally.

[0042] In all the above steps, when fabricating the blind slots or blind vias, precision control is required. Specifically, the thicknesses of the dielectric layers CS / L2, CS / L4, and CS / L6 need to be accurately calculated and verified with actual data from cross-section analysis. Additionally, the areas of L3, L4, and L7 where slots are to be made should be protected with PI tape of the same dielectric layer thickness to prevent scratches on the gold surface and reduce pressure marks.

[0043] When deep milling with a milling cutter, excess layers should be removed while controlling precision to ultimately form a blind slot. Key design considerations for blind slots: When the distance between blind slot edges is ≥5mm, the plating area should be extended 1.02mm (40mil) into the blind slot to prevent uneven copper thickness at the edges and to avoid non-conductive copper foil or circuitry being covered by dry film. When the distance between blind slot edges is <5mm, the copper area needs to be appropriately reduced to avoid delamination after lamination.

[0044] Compared with the prior art, the method for manufacturing a microwave board with small blind slots provided by the present invention includes the following steps: STEP 101: Manufacturing L1 / L2 layer: blanking → inner layer drilling → milling adhesive positioning frame → inner layer pretreatment → inner layer lamination → inner layer exposure → inner layer development → inner layer inspection → inner layer acid etching → inner layer film removal → inner layer AO I → browning → transfer bonding to outer layer manufacturing; STEP 102: Manufacturing L3 / L4 layer: blanking → substrate copper reduction → laser cutting tape → inner layer drilling → finished product cleaning machine → hole inspection → plasma → chemical copper (PTH) → electroplating copper → plasma; STEP 103: Manufacturing L5 / L6 layer: blanking → inner layer drilling → milling adhesive positioning frame → inner layer pretreatment → inner layer lamination → inner layer exposure → inner layer development → inner layer inspection → inner layer acid etching → inner layer film removal → inner layer AO I → browning → transfer bonding to outer layer manufacturing; I → Browning → Transfer lamination of outer layer fabrication; STEP 104: Fabrication of L7 / L8 layer: Material cutting → Inner layer drilling → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Pre-gold plating lamination → Pre-gold plating exposure → Pre-gold plating development → Electroplating hard gold → Post-gold plating stripping → Lamination and baking → Applying tape → Transfer lamination of outer layer fabrication; STEP 105: Lamination of L1 to L4 layers: Lamination → Milling → Measurement → Inner layer drilling → Finished product cleaning machine → Hole inspection → Plasma → Chemical copper → Electroplating copper → Plasma → Chemical copper → Copper thickening → Circuit inspection → Resin plugging → Resin grinding → Drilling → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AO I → Browning → Transfer lamination of outer layer fabrication; STEP 106: Lamination of L5 to L8 layers; STEP 107: Fabrication of PP; STEP 108: Lamination of L1 to L8: Lamination → Drilling → Small board cleaning → Hole inspection → First ion → Chemical copper → Electroplating of copper → Outer layer lamination → Outer layer exposure → Outer layer development → Circuit inspection → Pattern electroplating → Outer layer stripping → Outer layer alkaline etching → Outer layer tin stripping → Outer layer AO I → Chemical gold EN IG → Text → Long copy → Second drilling → First deep milling of blind groove → Second deep milling of blind groove → Third deep milling of blind groove → Milling → Finished product testing → FQC inspection → Packaging → FQA inspection → Completion of the fabrication of microwave board with fine blind grooves. The microwave board with fine blind grooves produced in this way not only has a lower cost, but also ensures a high yield.

[0045] The above are merely preferred embodiments of the present invention and are not intended to limit the scope of protection of the present invention. Any modifications, equivalent substitutions or improvements within the spirit of the present invention are covered within the scope of the claims of the present invention.

Claims

1. A method for manufacturing a microwave plate with tiny blind slots, comprising the following steps: STEP101: Fabrication of L1 / L2 layers: Material cutting → Inner layer drilling → Milling of adhesive positioning frame → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AOI → Browning → Transfer lamination of outer layer fabrication. STEP102: Fabrication of L3 / L4 layers: Material cutting → Copper reduction of substrate → Laser cutting of tape → Inner layer drilling → Finished product cleaning machine → Hole inspection → Plasma → Chemical copper (PTH) → Electroplating of copper → Plasma → Chemical copper → Copper thickening → Circuit inspection → Resin plugging → Resin grinding → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AOI → Lamination before gold plating → Exposure before gold plating → Development before gold plating → Hard gold plating → Stripping after gold plating → Lamination after inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Etching of gold plating wires → Inner layer AOI → Measure the expansion and contraction coefficients of layers 3-4, and obtain expansion and contraction data for the remaining layers → Pressing and baking → Applying tape. STEP103: Fabrication of L5 / L6 layer: Material cutting → Inner layer drilling → Milling of adhesive positioning frame → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AOI → Browning → Transfer lamination of outer layer fabrication. STEP104: Fabrication of L7 / L8 layer: Material cutting → Inner layer drilling → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer film removal → Inner layer AOI → Lamination before gold plating → Exposure before gold plating → Development before gold plating → Hard gold plating → Film removal after gold plating → Lamination and baking → Applying tape → Lamination of outer layer. STEP105: Lamination of L1 to L4 layers: Lamination → Milling → Measurement → Inner layer drilling → Finished product cleaning machine → Hole inspection → Plasma → Chemical copper → Electroplating of copper → Plasma → Chemical copper → Copper thickening → Circuit inspection → Resin plugging → Resin grinding → Drilling → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AOI → Browning → Transfer lamination to outer layer fabrication; STEP106: Lamination of L5 to L8 layers: Lamination → Milling → Measurement → Inner layer drilling → Finished product cleaning machine → Hole inspection → Milling of adhesive positioning frame → Plasma → Chemical copper → Electroplating of copper → Plasma → Chemical copper → Copper thickening → Circuit inspection → Resin plugging → Resin grinding → Inner layer pretreatment → Inner layer lamination → Inner layer exposure → Inner layer development → Inner layer inspection → Inner layer acid etching → Inner layer stripping → Inner layer AOI → Lamination before gold plating → Exposure before gold plating → Development before gold plating → Hard gold plating → Stripping after gold plating → Lamination after inner layer lamination → Exposure before inner layer development → Inner layer inspection → Etching of gold plating wires → Stripping of inner layer → Inner layer AOI → Browning → Applying adhesive tape → Transfer lamination to outer layer fabrication. STEP107: PP fabrication: lamination → PP drilling → PP milling → outer layer fabrication; STEP108: Lamination L1 to L8: Lamination → Drilling → Small board cleaning → Hole inspection → First ion → Chemical copper → Electroplating copper → Outer layer lamination → Outer layer exposure → Outer layer development → Circuit inspection → Pattern electroplating → Outer layer stripping → Outer layer alkaline etching → Outer layer tin stripping → Outer layer AOI → Chemical gold enig → Text → Long copy → Second drilling → First deep milling of blind slot → Second deep milling of blind slot → Third deep milling of blind slot → Milling → Finished product testing → FQC inspection → Packaging → FQA inspection → Completion of the small blind slot microwave board.

2. The method for fabricating a micro-blind slot microwave plate as described in claim 1, characterized in that: In STEP101, during the inner layer pretreatment, do not brush the board. During the inner layer exposure, the GTL layer is used as an auxiliary layer for full-surface exposure. The L2 layer is produced using the measured expansion and contraction file for the smooth surface. During the inner layer acid etching, the L2 layer is etched into a smooth surface.

3. The method for fabricating a micro-blind slot microwave plate as described in claim 1, characterized in that: In STEP102, during copper reduction of the substrate, micro-etching is performed to a thickness of 8-12 μm; during laser cutting of the tape, the tape thickness is 0.1 mm; during resin plugging, vacuum plugging is used, and high-frequency PTFE material is employed; during resin grinding, the thickness is reduced to 17-23 μm; during inner layer exposure, LDI is used, with a minimum front-side linewidth of 17.7 mil and a minimum front-side pitch of 16.5 mil; during inner layer acid etching, the etching tolerance is + / - 0.8 mil, the minimum linewidth is 14.2 mil, and the minimum pitch is 20 mil; during hard gold plating, the GTL nickel thickness is 4-7 μm, the GTL gold thickness is ≥0.05 μm, and the GTL hard gold plating area is 0.162 d / m². 2 .

4. The method for fabricating a microwave plate with tiny blind slots as described in claim 1, characterized in that: In STEP103, during inner layer exposure, layer L5 is used as an auxiliary layer for full-area exposure, while layer L6 is a smooth surface produced using measured expansion and contraction data. During inner layer acid etching, layer L6 is etched into a smooth surface.

5. The method for fabricating a micro-blind slot microwave plate as described in claim 1, characterized in that: In STEP104, during the inner layer exposure, when fabricating the L7 layer circuitry, the GBL layer serves as an auxiliary layer. The retained copper foil is produced based on the measured expansion and contraction data. The exposure equipment is an LDI, with a minimum front film linewidth of 17.2 mil and a minimum front film pitch of 16.5 mil. During the inner layer acid etching, the etching tolerance is + / - 0.8 mil, the minimum linewidth is 13.8 mil, and the minimum pitch is 20 mil. During the exposure before gold plating, L7 serves as an auxiliary layer, and the entire GBL layer is exposed as a positive film.

6. The method for fabricating a micro-blind slot microwave plate as described in claim 1, characterized in that: In STEP105, after laminating layers L1 to L4, the thickness tolerance of the laminated board is 1.15mm. During resin via plugging, the plugging method is vacuum plugging, and the plugging material is high-frequency PTFE. During inner layer exposure, the exposure equipment is LDIm reverse film with a minimum line width of 23.5mil and a minimum pitch of 16.5mil. The L4 layer circuit is fabricated, and the GTL layer is used as an auxiliary layer to retain the copper foil. During inner layer acid etching, the etching tolerance is + / - 0.8mil, the minimum line width after reverse etching is 20mil, and the minimum pitch after reverse etching is 20mil.

7. The method for fabricating a micro-blind slot microwave plate as described in claim 1, characterized in that: In STEP108, after laminating L1 to L8, the thickness of the laminated plate is 2.4728 mm. When laminating the outer layer, high-temperature tape should be applied first, followed by lamination. For outer layer exposure, the exposure equipment is LDI, with a minimum linewidth of 22 mil for the front film and a minimum pitch of 18 mil for the front film. The minimum linewidth for the reverse film is 17.7 mil, and the minimum pitch for the reverse film is 18 mil. During pattern plating, the GTL plating area is: 10.25, GBL electroplating area: 8.64, completed hole copper thickness: 30um. High-temperature tape must be applied first, then electroplating. During the outer alkaline etching, the etching tolerance is + / - 0.8mil. The minimum line width and minimum spacing of the front etching are 20mil and 20mil respectively. The minimum line width and minimum spacing of the back etching are 15.7mil and 20mil respectively. During the ENIG gold plating, the GTL nickel thickness is 3-5um, the GBL nickel thickness is 3-5um, the GTL gold thickness is ≥0.05um, the GBL gold thickness is ≥0.05um, the GTL gold plating area is 30%, and the GBL gold plating area is 48%. High-temperature tape is applied first, then the gold plating is performed externally.

8. The method for fabricating a micro-blind slot microwave plate as described in claim 1, characterized in that: When slotting or drilling, use PI tape of the same dielectric layer thickness to protect the gold surface from scratches and reduce foot marks at the slotted areas of layers L3, L4, and L7.

9. The method for fabricating a microwave plate with tiny blind slots as described in claim 1, characterized in that: When slotting, if the distance between the edges of the blind slots is ≥5mm, the electroplated area of ​​the circuit should be extended 1.02mm into the blind slot to prevent uneven copper thickness at the edges of the blind slots and to ensure that the non-conductive copper foil or circuit is covered by a dry film.

10. The method for fabricating a micro-blind slot microwave plate as described in claim 1, characterized in that: When slotting, if the distance between blind slot edges is less than 5mm, the copper area should be appropriately reduced to avoid delamination after lamination.