Precise ceramic circuit board

Abstract

The utility model discloses a precision ceramic circuit board, which comprises a ceramic substrate and a circuit layer arranged in the middle area of the two side surfaces of the ceramic substrate. The circuit layer comprises a plurality of circuit layer units which are arranged and distributed, the circuit layer units are arranged at intervals to form cutting grooves, and at least part of the cutting grooves are internally provided with gold-plated leads; the circuit layer comprises a copper plating layer arranged on the ceramic substrate, and a first initial groove and a second initial groove which are perpendicular to each other are formed after the copper plating layer is formed. The cutting groove is obtained by filling the first initial groove and the second initial groove with an auxiliary forming structure in the copper plating layer post-processing process for auxiliary forming. The precision ceramic circuit board is low in production cost, good in structural stability, high in precision of the circuit board, good in quality and high in production efficiency.

Description

Technical Field

[0001] The utility model relates to the technical field of ceramic-based circuit boards, in particular to a precision ceramic circuit board. Background Art

[0002] Compared with ordinary PCB circuit boards, precision ceramic circuit boards have better heat dissipation performance, current carrying capacity, insulation, thermal expansion coefficient, etc., and are therefore widely used in high-power power electronic modules, aerospace, military electronics and other products. However, the surface metallization cost of ceramic circuit boards in the prior art, including ceramic substrates in the products, is relatively high, which increases the overall production cost of the products, and thus makes the production cost of ceramic circuit boards significantly higher than that of traditional PCB circuit boards; the final products have defects such as poor flatness and right angles, low product quality, and low production efficiency. Therefore, how to reduce the production cost of ceramic circuit boards and improve product quality and production efficiency has become a technical problem that needs to be solved urgently. Utility Model Content

[0003] The purpose of the utility model is to solve the above problems and provide a precision ceramic circuit board; the precision ceramic circuit board has low production cost, good structural stability, high circuit board precision, good quality and high production efficiency.

[0004] In order to solve the above technical problems, the technical solution adopted by the utility model is as follows:

[0005] The utility model provides a precision ceramic circuit board, comprising a ceramic substrate, and a circuit layer arranged in the middle area of ​​the two side surfaces of the ceramic substrate; the circuit layer comprises a plurality of circuit layer units arranged and distributed, the circuit layer units are arranged at intervals to form cutting grooves, and at least part of the cutting grooves are provided with gold-plated leads; the circuit layer comprises a copper-plated layer arranged on the ceramic substrate, the copper-plated layer is formed to form a first initial groove and a second initial groove which are arranged perpendicular to each other after being formed, and the cutting groove is obtained by filling the first initial groove and the second initial groove with auxiliary forming structures respectively in the first initial groove and the second initial groove during the post-processing of the copper-plated layer.

[0006] Preferably, the cutting groove includes a first cutting groove and a second cutting groove formed by the first initial groove and the second initial groove respectively, and the gold-plated lead is arranged in the first initial groove; the circuit layer unit also includes a gold-plated layer arranged on a side of the copper-plated layer away from the ceramic substrate, and the gold-plated layer is deposited on the copper-plated layer by an electroplating gold process after the post-processing of the copper-plated layer is completed.

[0007] Preferably, the thickness of the gold-plated lead is smaller than the depth of the first initial groove and is at least 20 μm; the width of the gold-plated lead is smaller than the width of the first initial groove and is at least 100 μm.

[0008] Preferably, it also includes a third groove arranged on the first surface of the ceramic substrate and arranged parallel to the first cutting groove; after the copper plating layer is formed, a third initial groove arranged parallel to the first initial groove is formed on the ceramic substrate, and the third groove is obtained by filling the third initial groove with the auxiliary molding structure during the post-processing process of the copper plating layer.

[0009] Preferably, the auxiliary molding structure is made of photosensitive circuit ink, and the auxiliary molding structure is removed after the post-processing is completed; the gold-plated lead includes a copper gold-plated lead.

[0010] Preferably, it also includes a process edge copper layer arranged at the periphery of the circuit layer, the area corresponding to the process edge copper layer forms a process edge, and a cutting groove is arranged on the process edge in parallel with the cutting groove.

[0011] Preferably, the post-treatment of the copper-plated layer includes grinding and copper-reducing polishing treatment on the surface of the copper-plated layer.

[0012] The beneficial effects of the utility model include at least:

[0013] The precision ceramic circuit board of the utility model includes the cutting groove and other structures, which are formed by the auxiliary molding structure during the post-processing process of the copper-plated layer. The auxiliary molding structure is filled in the first initial groove and the second initial groove during the post-processing of the copper-plated layer. The auxiliary molding structure supports and protects the groove walls of the first initial groove and the second initial groove, and can resist the extrusion of the copper-plated layer during the post-processing process, improve the deformation or collapse of the groove wall, thereby ensuring the flatness and right angle of the product, improving the stability of the groove structure during the production process, improving the precision of the product, and ensuring the quality of the product; the gold-plated lead is arranged in the groove to provide a conductive basis for forming the gold-plated layer by the electroplating process, which reduces the production cost and improves the production efficiency compared with the chemical gold deposition in the prior art. In addition, the gold-plated lead is arranged in the cutting groove and can be cut and removed in the subsequent production process without affecting the use of a single independent product. BRIEF DESCRIPTION OF THE DRAWINGS

[0014] Figure 1 It is a structural schematic diagram of the first side of the precision ceramic circuit board of the utility model;

[0015] Figure 2 for Figure 1An enlarged schematic diagram of point A is shown;

[0016] Figure 3 This is a schematic diagram of the structure of the second side of the precision ceramic circuit board of the utility model;

[0017] Figure 4 for Figure 3 The enlarged schematic diagram of point B in the middle;

[0018] Figure 5 It is a partial structural schematic diagram of the first surface after a copper plating layer and a process copper layer are formed on a ceramic substrate;

[0019] Figure 6 It is a partial structural schematic diagram of the second surface after the copper plating layer and the process copper layer are formed on the ceramic substrate;

[0020] Figure 7 It is a schematic diagram of the cross section of the structure after the gold-plated leads are set;

[0021] Figure 8 It is a cross-sectional schematic diagram after the auxiliary forming structure is set;

[0022] Fig. 9 for Figure 8 Enlarged schematic diagram of point C in the middle.

[0023] Among them, 1-ceramic substrate, 2-circuit layer, 21-circuit layer unit, 211-copper plating layer, 22-cutting groove, 221-first cutting groove, 222-second cutting groove, 23-process edge copper layer, 24-third groove, 3-gold-plated lead, 41-first initial groove, 42-second initial groove, 43-third initial groove, 5-auxiliary molding structure, 6-process edge, 61-cutting groove, a-first surface, b-first surface. DETAILED DESCRIPTION

[0024] In order to facilitate the understanding of the present invention, the present invention will be described more fully below with reference to the relevant drawings. The preferred embodiments of the present invention are given in the drawings. However, the present invention can be implemented in many different forms and is not limited to the embodiments described herein. On the contrary, the purpose of providing these embodiments is to make the understanding of the disclosure of the present invention more thorough and comprehensive.

[0025] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art of the present invention. The terms used herein in the specification of the present invention are only for the purpose of describing specific embodiments and are not intended to limit the present invention.

[0026] In the present utility model, descriptions such as “first”, “second”, etc. are only used for descriptive purposes and cannot be understood as indicating or suggesting their relative importance or implicitly indicating the number of the indicated technical features.

[0027] The orientation or positional relationship indicated in the description of the present invention is based on the orientation or positional relationship shown in the accompanying drawings and is only for the convenience of describing the present invention and simplifying the description. It does not indicate or imply that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as a limitation on the present invention.

[0028] Example

[0029] See also Figures 1 to 6 The embodiment of the utility model provides a precision ceramic circuit board, which includes a ceramic substrate 1, and a circuit layer 2 arranged in the middle area of ​​the two side surfaces of the ceramic substrate 1; the circuit layer 2 includes a plurality of circuit layer units 21 arranged and distributed, and the circuit layer units 21 are spaced to form cutting grooves 22, and at least part of the cutting grooves 22 are provided with gold-plated leads 3; the circuit layer 2 includes a copper-plated layer 211 arranged on the ceramic substrate 1, and the copper-plated layer 211 is formed to form a first initial groove 41 and a second initial groove 42 arranged perpendicular to each other after molding, and the cutting groove 22 is obtained by filling the first initial groove 41 and the second initial groove 42 with auxiliary molding structures 5 respectively during the post-processing process of the copper-plated layer 211, and the auxiliary molding structure 5 is arranged on the side of the gold-plated lead 3 away from the ceramic substrate 1.

[0030] The precision ceramic circuit board of the utility model includes the cutting groove and other structures, which are formed by the auxiliary molding structure 5 during the post-processing process of the copper-plated layer 211. During the post-processing process of the copper-plated layer 211, the auxiliary molding structure 5 is filled in the first initial groove and the second initial groove. The auxiliary molding structure 5 supports and protects the groove walls of the first initial groove and the second initial groove, and can resist the extrusion of the copper-plated layer 211 during the post-processing process, improve the deformation or collapse of the groove wall, and thus ensure the flatness and right angle of the product, improve the stability of the groove structure during the production process, improve the precision of the product, and ensure the quality of the product; the gold-plated lead 3 is arranged in the groove to provide a conductive basis for forming a gold-plated layer by an electroplating process, which reduces the production cost and improves the production efficiency compared to the chemical gold deposition in the prior art. In addition, the gold-plated lead 3 is arranged in the cutting groove and can be cut and removed in the subsequent production process without affecting the use of a single independent product.

[0031] Further, the cutting groove 22 includes a first cutting groove 221 and a second cutting groove 222 formed by the first initial groove 41 and the second initial groove 42, respectively, and the gold-plated lead 3 is arranged in the first initial groove 41; correspondingly, after the first cutting groove 221 is formed in the first initial groove 41, the gold-plated lead is arranged in the first cutting groove 221, and the cross-sectional schematic diagram of the gold-plated lead after being arranged in the first cutting groove 221 is as shown in Figure 7 As shown; the circuit layer unit 21 also includes a gold-plated layer disposed on a side of the copper-plated layer 211 away from the ceramic substrate 1, and the gold-plated layer is deposited on the copper-plated layer 211 by an electroplating gold process after the post-treatment of the copper-plated layer 211 is completed.

[0032] The thickness of the gold-plated lead 3 is smaller than the depth of the first initial groove 41 and is at least 20 μm; the width of the gold-plated lead 3 is smaller than the width of the first initial groove 41 and is at least 100 μm.

[0033] The ceramic circuit board also includes a third groove 24 disposed on the first surface a of the ceramic substrate 1 and arranged parallel to the first cutting groove 221; after the copper plating layer 211 is formed, a third initial groove 43 disposed parallel to the first initial groove 41 is formed on the ceramic substrate 1, and the third groove 24 is obtained by filling the auxiliary molding structure 5 in the third initial groove 43 during the post-processing of the copper plating layer 211 to assist in molding; the cross-sectional schematic diagram of the auxiliary molding structure 5 filled in the groove structure is shown in Figure 8 and Fig. 9 In the process of post-processing the copper-plated layer 211, the auxiliary molding structure 5 is used to fill the first initial groove 41, the second initial groove 42 and the third initial groove 43, thereby preventing the groove structure in the circuit layer from deforming or collapsing during the process of post-processing the copper-plated layer, thereby ensuring the flatness and right angle of the product, improving the stability of the groove structure during the production process, improving the precision of the product, and ensuring the quality of the product.

[0034] In some embodiments, the auxiliary molding structure 5 is made of photosensitive circuit ink, and the auxiliary molding structure 5 is removed after the post-processing is completed; the gold-plated lead 3 includes a copper gold-plated lead 3.

[0035] The ceramic circuit board also includes a process edge copper layer 23 arranged on the periphery of the circuit layer 2, and the area corresponding to the process edge copper layer 23 forms a process edge 6, and a cutting groove 61 is arranged on the process edge 6 in parallel with the cutting groove 22.

[0036] The process edge copper layer 23 and the copper plating layer 211 are plated on the ceramic substrate 1 at the same time. When in use, the obtained precision ceramic circuit board is cut along the direction parallel to the cutting groove 61 to obtain a plurality of single products, and the gold-plated lead 3 in the first cutting groove 221 is also removed at the same time during cutting, thereby avoiding the gold-plated lead 3 from remaining. Preferably, a water jet is used to cut the obtained precision ceramic circuit board.

[0037] The post-processing of the copper plating layer 211 includes grinding and copper-reducing polishing of the surface of the copper plating layer 211 .

[0038] The present utility model also provides a method for manufacturing a precision ceramic circuit board, which is used to prepare the precision ceramic circuit board as described above, and comprises the steps of:

[0039] S1, providing a ceramic substrate 1, plating a copper plating layer 211 and a process copper layer 23 on a first surface a and a second surface b of the ceramic substrate 1, wherein a first initial groove 41 and a second initial groove 42 are arranged between the copper plating layers 211, and a third initial groove 43 parallel to the first initial groove 41 is also arranged on the copper plating layer 211 on the first surface a;

[0040] See specifically Figure 5 and Figure 6 As shown, the copper-plated layer 211 is deposited on the first surface a and the second surface b of the ceramic substrate 1, respectively, and the first initial groove 41, the second initial groove 42 and the third initial groove 43 are formed on the copper-plated layer of the first surface a, and the first initial groove 41 and the second initial groove 42 are formed on the copper-plated layer of the second surface b; the area corresponding to the copper-plated layer 211 forms the circuit layer of the high-precision ceramic circuit board, and the area corresponding to the process copper layer 23 forms the process edge of the high-precision ceramic circuit board;

[0041] S2, a gold-plated lead 3 is arranged in the first initial groove 41, and then the auxiliary molding structure 5 is filled in the first initial groove 41, the second initial groove 42 and the third initial groove 43. The structural cross-sectional schematic diagrams after the gold-plated lead 3 and the auxiliary molding structure 5 are respectively shown in the figure, that is, the auxiliary molding structure 5 is arranged on the side of the gold-plated lead 3 away from the ceramic substrate 1; then the copper-plated layer 211 obtained in step S1 is post-processed to further ensure the flatness of the product surface; after the post-processing is completed, the auxiliary molding structure 5 is removed to form a cutting groove 22 and a third groove 24; wherein, the cutting groove 22 includes a first cutting groove 221 and a second cutting groove 222 formed by the first initial groove 41 and the second initial groove 42 respectively;

[0042] S3, using an electroplating gold process to deposit a gold-plated layer on the side of the copper-plated layer 211 away from the surface of the ceramic substrate 1, and the gold-plated layer and the copper-plated layer 211 are stacked to form a circuit layer 2. Specifically, the copper-plated layer includes a plurality of copper-plated layer units arranged at intervals, the gold-plated layer includes a plurality of gold-plated layer units arranged corresponding to the copper-plated layer units, and the gold-plated layer units and the copper-plated layer units are stacked to form a circuit layer unit 21; the circuit layer units 21 are spaced apart to form the cutting grooves 22, and the third grooves 24 are arranged on the circuit layer units 21 and are arranged parallel to the first cutting grooves 221.

[0043] In the preparation method of the precision ceramic circuit board described in the utility model, the auxiliary molding structure 5 is filled in the initial groove before the copper plating layer 211 is post-processed, so as to support and protect the groove wall of the initial groove during the post-processing of the copper plating layer 211, so as to avoid the groove wall of the initial groove from being squeezed, collapsed and deformed during the post-processing process, thereby ensuring the flatness and right angle of the product, improving the precision of the product and improving the product quality; the gold plating layer is formed by electroplating with gold, which reduces the production cost and improves the production efficiency compared with the chemical gold deposition in the prior art, and the gold-plated lead 3 can be cut and removed in the subsequent production process without affecting the use of a single independent product.

[0044] The thickness of the gold-plated lead 3 is smaller than the depth of the first initial groove 41 and is at least 20 μm; the width of the gold-plated lead 3 is smaller than the width of the first initial groove 41 and is at least 100 μm.

[0045] In some embodiments, the auxiliary molding structure 5 is made of photosensitive circuit ink, and the auxiliary molding structure 5 is removed after the post-processing of the copper plating layer 211 is completed; the gold-plated lead 3 includes a copper gold-plated lead 3. The auxiliary molding structure 5 is filled in the initial groove, which specifically includes the steps of: using 36T screen printing for photosensitive circuit ink, heat-treating at 75°C for 25 minutes, exposing at 280mj energy, and developing. The removal of the auxiliary molding structure 5 specifically includes the steps of: soaking in a stripping solution for 5-10 minutes at a temperature of 50°C, and then washing and drying; the stripping solution is an alkaline stripping solution with a mass percentage of 5-10%; preferably, the alkaline stripping solution includes sodium hydroxide.

[0046] The technical features of the above embodiments may be combined arbitrarily. To make the description concise, not all possible combinations of the technical features in the above embodiments are described. However, as long as there is no contradiction in the combination of these technical features, they should be considered to be within the scope of this specification.

[0047] The above embodiments only express the preferred implementation of the utility model, and the description is relatively specific and detailed, but it cannot be understood as limiting the scope of the utility model patent. It should be pointed out that for ordinary technicians in this field, several modifications and improvements can be made without departing from the concept of the utility model, which all belong to the protection scope of the utility model. Therefore, the protection scope of the utility model patent shall be based on the attached claims.

Claims

1. A precision ceramic circuit board, characterized in that: The invention comprises a ceramic substrate, and a circuit layer arranged in the middle area of ​​the two side surfaces of the ceramic substrate; the circuit layer comprises a plurality of circuit layer units arranged and distributed, the circuit layer units are arranged at intervals to form cutting grooves, and at least some of the cutting grooves are provided with gold-plated leads; the circuit layer comprises a copper-plated layer arranged on the ceramic substrate, the copper-plated layer is formed to form a first initial groove and a second initial groove arranged perpendicular to each other after being formed, and the cutting groove is obtained by filling the first initial groove and the second initial groove with auxiliary forming structures in the post-processing process of the copper-plated layer.

2. The precision ceramic circuit board according to claim 1, characterized in that: The cutting groove includes a first cutting groove and a second cutting groove formed by the first initial groove and the second initial groove respectively, and the gold-plated lead is arranged in the first initial groove; the circuit layer unit also includes a gold-plated layer arranged on a side of the copper-plated layer away from the ceramic substrate, and the gold-plated layer is deposited on the copper-plated layer by using an electroplating gold process after the post-treatment of the copper-plated layer is completed.

3. The precision ceramic circuit board according to claim 2, characterized in that: The thickness of the gold-plated lead is smaller than the depth of the first initial groove and is at least 20 μm; the width of the gold-plated lead is smaller than the width of the first initial groove and is at least 100 μm.

4. The precision ceramic circuit board according to claim 2, characterized in that: It also includes a third groove disposed on the first surface of the ceramic substrate and arranged parallel to the first cutting groove; After the copper plating layer is formed, a third initial groove parallel to the first initial groove is formed on the ceramic substrate. The third groove is formed by filling the third initial groove with the auxiliary forming structure during post-processing of the copper plating layer.

5. The precision ceramic circuit board according to claim 1, characterized in that: The auxiliary molding structure is made of photosensitive circuit ink, and the auxiliary molding structure is removed after the post-processing is completed; the gold-plated lead wire includes a copper gold-plated lead wire.

6. The precision ceramic circuit board according to claim 1, characterized in that: It also includes a process edge copper layer arranged on the periphery of the circuit layer, the area corresponding to the process edge copper layer forms a process edge, and a cutting groove is arranged on the process edge in parallel with the cutting groove.

7. The precision ceramic circuit board according to claim 1, characterized in that: The post-treatment of the copper-plated layer includes a grinding and copper-reducing polishing treatment on the surface of the copper-plated layer.

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