Method for electroplating nickel and gold on ceramic copper-clad substrate

Abstract

The invention discloses a nickel and gold electroplating method for a ceramic copper-clad substrate. The nickel and gold electroplating method sequentially comprises the following steps that S1, the ceramic substrate is covered with a complete copper surface; s2, performing film coating operation on a non-plating area, which does not need to be plated with a metal plating layer, on the copper surface, and exposing a to-be-plated area, which needs to be plated with a metal plating layer, on the copper surface; s3, the whole copper surface is electroplated, so that the to-be-plated area is fully plated with a metal plating layer; s4, carrying out film removal operation on a non-plating area on the copper surface; s5, covering an anti-etching protective film on a reserved region at least comprising the region to be plated on the copper surface, and exposing an etching region; and S6, wet etching is carried out on the copper surface, so that the copper surface in the etching region is etched. According to the invention, a metal coating with a large thickness can be electroplated, and an area corresponding to the metal coating can be formed on the copper surface.

Description

Technical Field

[0001] The invention relates to the technical field of printed circuit boards, and in particular to a method for electroplating nickel and gold on a ceramic copper-clad substrate. Background Art

[0002] In conventional chemical nickel-gold plating processes, the nickel thickness of ceramic copper clad substrate products (DCB / AMB / DPC / DBA) can only be plated to 10um, and the gold thickness can only be plated to 100nm. Due to functional requirements, the nickel-gold thickness of some products needs to be greater than the limit of the current existing process.

[0003] like Figure 1 As shown, in the process of chemical nickel-gold plating on the existing ceramic copper-clad substrate, firstly, a copper-cladding operation is performed on the substrate to cover the substrate with a copper surface 1, and then the copper-clad substrate is subjected to a partitioned film coating to cover each of the to-be-plated areas 3 that need to be plated with nickel-gold, and an etching area 2 that needs to be etched is left between each of the to-be-plated areas 3, and then an etching operation is performed on the substrate after the partitioned film coating is completed, and the copper surface 1 located in the etching area 2 is etched, and then the etching area 2 on the etched substrate is subjected to a secondary film coating to leave the to-be-plated area 3 that needs to be chemically plated with nickel-gold, and finally the substrate subjected to the secondary film coating is subjected to chemical plating. Nickel gold, but due to the limitation of the basic principle of chemical plating, after the coating is fully plated on the coating, the thickness of the coating is difficult to increase. At the same time, if the substrate that has undergone secondary coating is directly electroplated, since the copper surfaces 1 in each area 3 to be plated are separated from each other, it is necessary to connect the copper surfaces 1 in each area 3 to be plated with wires before electroplating. There are many wires to be connected, and according to actual needs, some areas 3 to be plated have very small areas, and it is difficult to firmly connect the wires to the copper surfaces 1 in the areas 3 to be plated. Therefore, the existing ceramic copper-clad substrate chemical nickel-gold plating process is difficult to achieve a nickel-gold plating layer of higher thickness. Summary of the invention

[0004] The object of the present invention is to provide a method for electroplating nickel and gold on a ceramic copper-clad substrate, which can electroplate a metal coating with a relatively large thickness and form an area on the copper surface corresponding to the metal coating.

[0005] In order to solve the above technical problems, the present invention adopts the following solutions: A method for electroplating nickel and gold on a ceramic copper-clad substrate comprises the following steps in sequence: Step S1, covering a complete copper surface on a ceramic substrate; Step S2, laminating the unplated area on the copper surface that does not need to be plated with a metal coating, exposing the to-be-plated area on the copper surface that needs to be plated with a metal coating; Step S3, electroplating the entire copper surface so that the area to be plated is fully plated with a metal coating; Step S4, performing a film removal operation on the non-plating area on the copper surface; Step S5, covering the reserved area on the copper surface including at least the to-be-plated area with an anti-etching protective film, exposing the etching area; Step S6, wet-etching the copper surface so that the copper surface in the etching area is etched. The non-plated area and the area to be plated are complementary to fill the copper surface, and the reserved area and the etching area are complementary to fill the copper surface. The etching method is specifically pickling wet etching. The electroplating and etching of the entire copper surface can be carried out using existing technology, which is unnecessary to elaborate. After step S6, the protective film on the area to be plated is removed to obtain the finished product. Its function is that, by first electroplating the area to be plated and then etching the copper surface, compared with the method of first etching the copper surface and then electroplating the etched copper surface in the prior art, it can avoid the difficulty of wiring on the separated copper surfaces, and can use the advantages of electroplating itself to form a thicker metal coating.

[0006] Furthermore, in a top-down view of the copper surface, the reserved area completely overlaps with the area to be plated, and the non-plated area completely overlaps with the etched area.

[0007] Furthermore, in a top view of the copper surface, at least one to-be-plated area is provided in each reserved area, and the area of ​​the to-be-plated area in each reserved area is smaller than the area of ​​the reserved area, the etching area is located in the non-plating area, and the area of ​​the etching area is smaller than the area of ​​the non-plating area, and the protective film on the reserved area includes a first height located on the top surface of the metal plating layer and a second height located on the top surface of the copper surface, There are at least two areas to be plated, and every two adjacent areas to be plated are separated from each other. There are at least two reserved areas, and every two adjacent reserved areas are separated from each other. The function is that, since some finished ceramic copper-clad substrates need to have a copper surface that is not plated with a metal coating, through the size relationship between the reserved area and the area to be plated, a part of the unplated copper surface can be left in the area outside the area to be plated in the reserved area on the finished product.

[0008] Furthermore, in step S3, the metal plating layer is a nickel layer or a gold layer.

[0009] Furthermore, the metal plating layer is a nickel layer, and the thickness of the metal plating layer is 10-20um.

[0010] Furthermore, the metal plating layer is a gold layer, and the thickness of the metal plating layer is 100-200nm.

[0011] Furthermore, there are at least two areas to be plated, and every two adjacent areas to be plated are separated from each other.

[0012] Furthermore, in step S2, the following steps are included in sequence: Step S2a, covering the copper surface with a complete dry film; Step S2b, placing a film having a non-plating area pattern between an exposure light source and the dry film on the copper surface; Step S2c, performing exposure operation on the dry film, so that the dry film remains in the non-plating area and the area to be plated is exposed. The film itself is an existing technology used for light shielding during the exposure and imaging process, and the dry film is an existing material commonly used in the exposure and imaging and etching processes. The exposure operation of the dry film is a common existing technology and will not be described in detail.

[0013] Furthermore, in step S5, the following steps are sequentially included: Step S5a, covering the metal plating layer on the copper surface with a complete dry film; Step S5b, placing the film including the reserved area pattern between the exposure light source and the dry film on the copper surface; Step S5c: Expose the dry film so that the dry film remains on the reserved area and the etched area is exposed. The dry film serves as a protective film.

[0014] Furthermore, in step S5b, when the reserved area completely overlaps with the area to be plated, the non-plated area completely overlaps with the etched area, and the distance between each two areas to be plated is greater than twice the thickness of the metal coating, the hollowed-out area of ​​the film used includes a corresponding area corresponding to the shape and size of the area to be plated, an extension area is provided on the outer contour of the corresponding area, and a shading block is provided at the angle between each two bent and extended shading areas. Its function is to enable the extension area on the side wall of each corresponding area to be folded down separately through the provision of the shading block, so as to cover the side wall of the metal coating, thereby avoiding damage to the integrity of the metal coating during the etching process of the metal coating as much as possible.

[0015] Furthermore, the width of the extended area is equal to the thickness of the metal coating, and in the top view of the ceramic substrate during the exposure process, the corresponding area overlaps with the area to be plated. After step S5, air is blown toward the dry film so that the area on the dry film corresponding to the extended area is attached to the side wall of the metal coating.

[0016] Furthermore, in step S5, the following steps are sequentially included: Step S51, covering each reserved area with a thermoplastic material; Step S52: heating the thermoplastic material so that the thermoplastic material covers each outer surface in the reserved area to form a protective film.

[0017] Furthermore, in step S5, the following steps are sequentially included: Step S5A, covering the metal plating layer on the copper surface with a dry film; Step S5B, vacuum treatment is performed on the copper surface to make the dry film close to the side wall of the metal coating; Step S5C, placing the film with the reserved area pattern between the exposure light source and the dry film on the copper surface; Step S5D: Expose the dry film so that the dry film remains on the reserved area and the etched area is exposed. The dry film serves as a protective film.

[0018] The present invention has the beneficial effects: 1. By first electroplating the area to be plated and then etching the copper surface, compared with the method of first etching the copper surface and then electroplating the etched copper surface in the prior art, the difficulty of wiring on the separated copper surfaces can be avoided, and the advantages of electroplating itself can be used to form a thicker plating layer; 2. By setting the shading block, the expansion area on the side wall of each corresponding area can be folded down separately, so as to cover the side wall of the metal coating, thereby avoiding damage to the integrity of the metal coating during the etching process of the metal coating as much as possible. BRIEF DESCRIPTION OF THE DRAWINGS

[0019] Figure 1 The present invention is a process flow chart of chemical nickel-gold plating on ceramic copper-clad substrate in the prior art; Figure 2 It is the process flow chart of Example 1; Figure 3 is a cross-sectional schematic diagram of the ceramic substrate after step S1 of Example 1; Figure 4 is a schematic cross-sectional view of the ceramic substrate after step S2a of Example 1; Figure 5 is a cross-sectional schematic diagram of the ceramic substrate in step S2b of Example 1; Figure 6 is a schematic cross-sectional view of the ceramic substrate after step S2c of Example 1; Figure 7 is a cross-sectional schematic diagram of the ceramic substrate after step S3 of Example 1; Figure 8 is a cross-sectional schematic diagram of the ceramic substrate after step S4 of Example 1; Fig. 9 is a cross-sectional schematic diagram of the ceramic substrate in step S5b of Example 1; Fig.10 is a schematic cross-sectional view of the ceramic substrate after step S5c of Example 1; Fig.11 is a cross-sectional schematic diagram of the ceramic substrate after step S6 of Example 1; Fig.12 is a schematic top view of the film used in step S2b of Example 1; Fig.13 is a schematic top view of the film used in step S5b of Example 1; Fig.14 is a schematic top view of the film used in step S5b of Example 2; Fig.15 Schematic top view of the ceramic substrate before blowing after step S5c of Example 2; Fig.16 is a cross-sectional schematic diagram of the ceramic substrate after blowing in step S5c of Example 2; Fig.17 It is the process flow chart of Example 3; Fig.18 is a cross-sectional schematic diagram of the ceramic substrate after step S4 of Example 3; Fig.19 is a cross-sectional schematic diagram of a ceramic substrate using a dry film as a protective film in step S5 of Example 3; Fig. 20 is a cross-sectional schematic diagram of a ceramic substrate using a thermoplastic material as a protective film in step S5 of Example 3; Fig.21 Schematic cross-sectional view of the ceramic substrate after the protective film is removed in step S6 of Example 3.

[0020] Figure numerals: 1, copper surface; 2, etching area; 3, area to be plated; 4, metal coating; 5, dry film; 6, film; 7, exposure light source; 8, corresponding area; 9, extension area; 10, shading block; 11, ceramic substrate; 12, non-plating area; 13, reserved area; 14, thermoplastic material. DETAILED DESCRIPTION

[0021] The present invention will be further described in detail below in conjunction with embodiments and drawings, but the embodiments of the present invention are not limited thereto.

[0022] In the description of the present invention, it should be noted that the terms "center", "up", "down", "left", "right", "vertical", "longitudinal", "lateral", "horizontal", "inside", "outside", "front", "back", "top", "bottom" and the like indicate directions or positional relationships based on the directions or positional relationships shown in the accompanying drawings, or are the directions or positional relationships in which the inventive product is usually placed when used. They are only for the convenience of describing the present invention and simplifying the description, and do not indicate or imply that the device or element referred to must have a specific direction, be constructed and operated in a specific direction, and therefore should not be understood as a limitation on the present invention.

[0023] In the description of the present invention, it is also necessary to explain that, unless otherwise clearly specified and limited, the terms "disposed", "opened", "installed", "connected", and "connected" should be understood in a broad sense, for example, it can be a fixed connection, a detachable connection, or an integral connection; it can be a mechanical connection or an electrical connection; it can be a direct connection, or it can be indirectly connected through an intermediate medium, or it can be the internal communication of two components. For ordinary technicians in this field, the specific meanings of the above terms in the present invention can be understood according to specific circumstances.

[0024] Example 1 A method for electroplating nickel and gold on a ceramic copper-clad substrate, such as Figure 2 As shown, the following steps are included in sequence: Step S1: Figure 3 As shown, a complete copper surface 1 is covered on a ceramic substrate 11; Step S2, laminating the non-plated area 12 on the copper surface 1 that does not need to be plated with a metal coating, exposing the to-be-plated area 3 on the copper surface 1 that needs to be plated with a metal coating 4; Step S3: Figure 7 As shown, the entire copper surface 1 is electroplated so that the area to be plated 3 is fully plated with a metal coating 4; Step S4: Figure 8 As shown, the non-plating area 12 on the copper surface 1 is subjected to a film stripping operation; Step S5, covering the reserved area 13 of the copper surface 1 including at least the area to be plated 3 with an anti-etching protective film, exposing the etching area 2 on the copper surface 1 that needs to be etched; Step S6: Fig.11 As shown, the copper surface 1 is wet-etched so that the copper surface 1 in the etching area 2 is etched. The electroplating and etching of the entire copper surface 1 can be carried out by using the existing technology, and no further description is required. Its function is that by first electroplating the area to be plated 3 and then etching the copper surface 1, compared with the method of first etching the copper surface 1 and then electroplating the etched copper surface 1 in the prior art, it can avoid the difficulty of wiring on the separated copper surfaces 1, and can use the advantages of electroplating itself to form a thicker coating.

[0025] In a top view of the copper surface 1 , the reserved area 13 completely overlaps with the area to be plated 3 , and the non-plated area 12 completely overlaps with the etched area 2 .

[0026] In the step S3, the metal plating layer 4 is a nickel layer or a gold layer.

[0027] The metal coating 4 is a nickel layer, and the thickness of the metal coating 4 is 10-20 um.

[0028] The metal plating layer 4 is a gold layer, and the thickness of the metal plating layer 4 is 100-200 nm.

[0029] There are at least two areas 3 to be plated, and every two adjacent areas 3 to be plated are separated from each other.

[0030] In step S2, the following steps are sequentially included: Step S2a, such as Figure 4 As shown, a complete dry film 5 is covered on the copper surface 1; Step S2b: Figure 5 As shown, Fig.12 The film 6 having the pattern of the non-plating area 12 is placed between the exposure light source 7 and the dry film 5 on the copper surface 1; Step S2c: Figure 6 As shown, the dry film 5 is exposed to light, so that the dry film 5 remains in the non-plating area 12, while exposing the area to be plated 3. The film 6 itself is a prior art for shielding light during the exposure and imaging process, and will not be described in detail.

[0031] In the step S5, the following steps are sequentially included: Step S5a, covering the metal plating layer 4 on the copper surface 1 with the complete dry film 5; Step S5b: Fig. 9 As shown, Fig.13 The film 6 including the pattern of the reserved area 13 is shown to be placed between the exposure light source 7 and the dry film 5 on the copper surface 1; Step S5c: Fig.10 As shown, the dry film 5 is exposed to light, so that the dry film 5 remains on the reserved area 13 and the etched area 2 is exposed. The dry film 5 serves as a protective film.

[0032] The working principle of this embodiment is described as follows: by the method of electroplating first and then etching, the copper surface 1 is electroplated in a complete state, so that the entire copper surface 1 acts as a continuous conductor, and only one wire can be used to electroplate all the areas to be plated 3 on the entire copper surface 1, so that the areas to be plated 3 form a metal coating 4 of the required thickness, and then the copper surface 1 in the etching area 2 is etched. At the same time, since electroplating can form a thicker coating than chemical plating, a thicker coating can be plated on the ceramic copper-clad substrate, and plating can be achieved even for multiple copper surfaces 1 separated from each other or even for copper surfaces 1 with a very small area.

[0033] Example 2 A method for electroplating nickel and gold on a ceramic copper-clad substrate comprises the following steps in sequence: Step S1, covering a complete copper surface 1 on a ceramic substrate 11; Step S2, performing a lamination operation on the non-plated area 12 on the copper surface 1 that does not need to be plated with the metal plating layer 4, exposing the to-be-plated area 3 on the copper surface 1 that needs to be plated with the metal plating layer 4; Step S3, electroplating the entire copper surface 1, so that the area to be plated 3 is fully plated with a metal coating 4; Step S4, performing a film removal operation on the non-plating area 12 on the copper surface 1; Step S5, covering the reserved area 13 of the copper surface 1 including at least the area to be plated 3 with an anti-etching protective film, exposing the etching area 2 on the copper surface 1 that needs to be etched; Step S6, wet-etching the copper surface 1, so that the copper surface 1 in the etching area 2 is etched. The electroplating and etching of the entire copper surface 1 can be carried out by using existing technologies, and no further description is required. Its function is that, by first electroplating the area to be plated 3 and then etching the copper surface 1, compared with the method of first etching the copper surface 1 and then electroplating the etched copper surface 1 in the prior art, it can avoid the difficulty of wiring on the separated copper surfaces 1, and can use the advantages of electroplating itself to form a thicker coating.

[0034] In a top view of the copper surface 1 , the reserved area 13 completely overlaps with the area to be plated 3 , and the non-plated area 12 completely overlaps with the etched area 2 .

[0035] In the step S3, the metal plating layer 4 is a nickel layer or a gold layer.

[0036] The metal coating 4 is a nickel layer, and the thickness of the metal coating 4 is 10-20 um.

[0037] The metal plating layer 4 is a gold layer, and the thickness of the metal plating layer 4 is 100-200 nm.

[0038] There are at least two areas 3 to be plated, and every two adjacent areas 3 to be plated are separated from each other.

[0039] In step S2, the following steps are sequentially included: Step S2a, covering the copper surface 1 with a complete dry film 5; Step S2b: Fig.14 The film 6 having the pattern of the etched area 2 is placed between the exposure light source 7 and the dry film 5 on the copper surface 1; Step S2c, performing exposure operation on the dry film 5, so that the dry film 5 remains in the etching area 2, and at the same time, the area to be plated 3 is exposed. The film 6 itself is an existing technology for shielding during the exposure and imaging process, and will not be described in detail.

[0040] In the step S5, the following steps are sequentially included: Step S5a, covering the metal plating layer 4 on the copper surface 1 with the complete dry film 5; Step S5b: Fig.15 The film 6 including the pattern of the area to be plated 3 is placed between the exposure light source 7 and the dry film 5 on the copper surface 1; Step S5c, performing an exposure operation on the dry film 5, so that the dry film 5 remains on the to-be-plated area 3, while exposing the etched area 2. The dry film 5 serves as a protective film.

[0041] In the step S5b, when the reserved area 13 completely overlaps with the to-be-plated area 3, the non-plated area 12 completely overlaps with the etched area 2, and the distance between every two reserved areas 13 is greater than twice the thickness of the metal plating layer 4, Fig.14 As shown, the hollowed-out area of ​​the film 6 used includes a corresponding area 8 corresponding to the shape and size of the area to be plated 3, an expansion area 9 is provided on the outer contour of the corresponding area 8, and a shading block 10 is provided at the angle between each two bent and extended shading areas. Its function is that, through the provision of the shading block 10, the expansion area 9 on the side wall of each corresponding area 8 can be folded down separately, so as to cover the side wall of the metal plating layer 4, and to avoid damaging the integrity of the metal plating layer 4 during the etching process of the metal plating layer 4 as much as possible.

[0042] The width of the extended area 9 is equal to the thickness of the metal coating 4. In the top view of the ceramic substrate 11 during the exposure process, the corresponding area 8 overlaps with the area to be plated 3. like Fig.16 As shown, after step S5 , air is blown toward the dry film 5 so that the area on the dry film 5 corresponding to the extended area 9 is attached to the side wall of the metal coating 4 .

[0043] The working principle of this embodiment is described as follows: Since the coating is performed by electroplating first and then etching, the side walls of the metal coating 4 are easily damaged during the etching process. Therefore, it is necessary to consider the protection of the side walls of the metal coating 4. By setting the extension area 9, the extension area 9 can be bent downward to cover the side walls of the metal coating 4 after blowing, thereby achieving the protection of the side walls of the metal coating 4 during the etching process.

[0044] Example 3 A method for electroplating nickel and gold on a ceramic copper-clad substrate, such as Fig.17 As shown, the following steps are included in sequence: Step S1, covering a complete copper surface 1 on a ceramic substrate 11; Step S2, performing a lamination operation on the non-plated area 12 on the copper surface 1 that does not need to be plated with the metal plating layer 4, exposing the to-be-plated area 3 on the copper surface 1 that needs to be plated with the metal plating layer 4; Step S3, electroplating the entire copper surface 1, so that the area to be plated 3 is fully plated with a metal coating 4; Step S4: Fig.18 As shown, the non-plating area 12 on the copper surface 1 is subjected to a film stripping operation; Step S5, covering the reserved area 13 of the copper surface 1 including at least the area to be plated 3 with an anti-etching protective film, exposing the etching area 2 on the copper surface 1 that needs to be etched; Step S6: Fig.21 As shown, the copper surface 1 is wet-etched so that the copper surface 1 in the etching area 2 is etched. The electroplating and etching of the entire copper surface 1 can be carried out by using the existing technology, and no further description is required. Its function is that by first electroplating the area to be plated 3 and then etching the copper surface 1, compared with the method of first etching the copper surface 1 and then electroplating the etched copper surface 1 in the prior art, it can avoid the difficulty of wiring on the separated copper surfaces 1, and can use the advantages of electroplating itself to form a thicker metal coating 4.

[0045] In a top view of the copper surface 1, at least one to-be-plated area 3 is provided in each reserved area 13, and the area of ​​the to-be-plated area 3 in each reserved area 13 is smaller than the area of ​​the reserved area 13; the etching area 2 is located in the non-plating area 12, and the area of ​​the etching area 2 is smaller than the area of ​​the non-plating area 12; the protective film on the reserved area 13 includes a first height located on the top surface of the metal plating layer 4 and a second height located on the top surface of the copper surface 1; There are at least two areas to be plated 3, and every two adjacent areas to be plated 3 are separated from each other. There are at least two reserved areas 13, and every two adjacent reserved areas 13 are separated from each other. The function is that, since some finished ceramic copper-clad substrates need to have a copper surface 1 that is not plated with a metal coating 4, the size relationship between the reserved area 13 and the area to be plated 3 allows a portion of the unplated copper surface 1 to be left in the area outside the area to be plated 3 in the reserved area 13 on the finished product.

[0046] In the step S3, the metal plating layer 4 is a nickel layer or a gold layer.

[0047] The metal coating 4 is a nickel layer, and the thickness of the metal coating 4 is 10-20 um.

[0048] The metal plating layer 4 is a gold layer, and the thickness of the metal plating layer 4 is 100-200 nm.

[0049] In step S2, the following steps are sequentially included: Step S2a, covering the copper surface 1 with a complete dry film 5; Step S2b, placing the film 6 having the pattern of the non-plating area 12 between the exposure light source 7 and the dry film 5 on the copper surface 1; Step S2c, performing exposure operation on the dry film 5, so that the dry film 5 remains in the non-plating area 12, and at the same time, the area to be plated 3 is exposed. The film 6 itself is an existing technology for shielding during the exposure and imaging process, and will not be described in detail.

[0050] In the step S5, the following steps are sequentially included: Step S51, coating each reserved area 13 with a thermoplastic material 14; Step S52: Fig. 20As shown, the thermoplastic material 14 is heated so that the thermoplastic material 14 covers each outer surface in the reserved area 13 to form a protective film. The thermoplastic material 14 is a prior art, such as hot melt adhesive, heat shrink film, thermoplastic dry film 5, etc. Its function is that since the reserved area 13 has a high metal plating layer 4 and a low copper surface 1, in order to make the reserved area 13 have a protective film with a first height and a second height of different heights, and at the same time make the protective film able to fill the side of the metal plating layer 4, to avoid Fig.19 When the dry film 5 is directly used as the protective film, a gap is left between the section between the first height and the second height on the protective film and the side wall of the metal coating 4, causing the etching liquid to penetrate. Using thermoplastic material 14 as the protective film can effectively avoid this problem.

[0051] The remaining steps and principles are the same as those in Example 1.

[0052] Example 4 A method for electroplating nickel and gold on a ceramic copper-clad substrate comprises the following steps in sequence: Step S1, covering a complete copper surface 1 on a ceramic substrate 11; Step S2, laminating the non-plated area 12 on the copper surface 1 that does not need to be plated with a metal coating, exposing the to-be-plated area 3 on the copper surface 1 that needs to be plated with a metal coating 4; Step S3, electroplating the entire copper surface 1, so that the area to be plated 3 is fully plated with a metal coating 4; Step S4, performing a film removal operation on the non-plating area 12 on the copper surface 1; Step S5, covering at least the reserved area 13 of the copper surface 1 including the area to be plated with an anti-etching protective film, exposing the etching area 2 on the copper surface that needs to be etched; Step S6, wet-etching the copper surface 1, so that the copper surface 1 in the etching area 2 is etched. The electroplating and etching of the entire copper surface 1 can be carried out by using existing technologies, and no further description is required. Its function is that, by first electroplating the area to be plated 3 and then etching the copper surface 1, compared with the method of first etching the copper surface 1 and then electroplating the etched copper surface 1 in the prior art, it can avoid the difficulty of wiring on the separated copper surfaces 1, and can use the advantages of electroplating itself to form a thicker metal coating 4.

[0053] In a top view of the copper surface, at least one to-be-plated area 3 is provided in each reserved area 13, and the area of ​​the to-be-plated area 3 in each reserved area 13 is smaller than the area of ​​the reserved area 13; the etching area 2 is located in the non-plating area 12, and the area of ​​the etching area 2 is smaller than the area of ​​the non-plating area 12; the protective film on the reserved area 13 includes a first height located on the top surface of the metal plating layer 4 and a second height located on the top surface of the copper surface 1; There are at least two areas to be plated 3, and every two adjacent areas to be plated 3 are separated from each other. There are at least two reserved areas 13, and every two adjacent reserved areas 13 are separated from each other. The function is that, since some finished ceramic copper-clad substrates need to have a copper surface 1 that is not plated with a metal coating 4, the size relationship between the reserved area 13 and the area to be plated 3 allows a portion of the unplated copper surface 1 to be left in the area outside the area to be plated 3 in the reserved area 13 on the finished product.

[0054] In the step S3, the metal plating layer 4 is a nickel layer or a gold layer.

[0055] The metal coating 4 is a nickel layer, and the thickness of the metal coating 4 is 10-20 um.

[0056] The metal plating layer 4 is a gold layer, and the thickness of the metal plating layer 4 is 100-200 nm.

[0057] In step S2, the following steps are sequentially included: Step S2a, covering the copper surface 1 with a complete dry film 5; Step S2b, placing the film 6 having the pattern of the non-plating area 12 between the exposure light source 7 and the dry film 5 on the copper surface 1; Step S2c, performing exposure operation on the dry film 5, so that the dry film 5 remains in the non-plating area 12, and at the same time, the area to be plated 3 is exposed. The film 6 itself is an existing technology for shielding during the exposure and imaging process, and will not be described in detail.

[0058] In the step S5, the following steps are sequentially included: Step S5A, covering the metal plating layer 4 on the copper surface 1 with a dry film 5; Step S5B, vacuum treatment is performed on the copper surface 1 to make the dry film 5 close to the side wall of the metal plating layer 4; Step S5C, placing the film 6 having the pattern of the etching area 2 between the exposure light source 7 and the dry film 5 on the copper surface 1; Step S5D, performing an exposure operation on the dry film 5, so that the dry film 5 remains on the area to be plated 3, while exposing the etching area 2. The dry film 5 serves as a protective film. Its function is that, since the reserved area 13 has a relatively high metal plating layer 4 and a relatively low copper surface 1, in order to make the reserved area 13 have a protective film with a first height and a second height of different heights, and at the same time make the protective film fill the side of the metal plating layer 4, and avoid leaving a gap between the section between the first height and the second height on the protective film and the side wall of the metal plating layer 4, which causes the etching liquid to penetrate, the method of vacuum treatment of the copper surface 1 covered with the dry film 5 can effectively avoid the occurrence of this problem.

[0059] The remaining steps and principles are the same as those in Example 1.

[0060] The above description is only a preferred embodiment of the present invention and does not limit the present invention in any form. According to the technical essence of the present invention, within the spirit and principles of the present invention, any simple modification, equivalent replacement and improvement made to the above embodiment still falls within the protection scope of the technical solution of the present invention.

Claims

1. A method for electroplating nickel and gold on a ceramic copper-clad substrate, characterized in that: The following steps are included in sequence: Step S1, covering a complete copper surface (1) on a ceramic substrate (11); Step S2, performing a lamination operation on the non-plated area (12) on the copper surface (1) that does not need to be plated with the metal coating (4), thereby exposing the to-be-plated area (3) on the copper surface (1) that needs to be plated with the metal coating (4); Step S3, electroplating the entire copper surface (1) so that the area to be plated (3) is fully plated with a metal coating (4); Step S4, performing a film removal operation on the non-plating area (12) on the copper surface (1); Step S5, covering the reserved area (13) on the copper surface (1) including at least the area to be plated (3) with an anti-etching protective film, thereby exposing the etching area (2) on the copper surface (1) that needs to be etched; Step S6, wet-etching the copper surface (1) so that the copper surface (1) in the etching area (2) is etched.

2. A method for electroplating nickel-gold on a ceramic copper-clad substrate according to claim 1, characterized in that: In a top-down view of the copper surface (1), the reserved area (13) completely overlaps with the area to be plated (3), and the non-plated area (12) completely overlaps with the etched area (2).

3. The method for electroplating nickel-gold on a ceramic copper-clad substrate according to claim 1, characterized in that: In a top view of the copper surface (1), each reserved area (13) is provided with at least one area to be plated (2), and the area of ​​the area to be plated (3) in each reserved area (13) is smaller than the area of ​​the reserved area (13); the etching area (2) is located in the non-plating area (12), and the area of ​​the etching area (2) is smaller than the area of ​​the non-plating area (12); and the protective film on the reserved area (13) comprises a first height located on the top surface of the metal plating layer and a second height located on the top surface of the copper surface; There are at least two to-be-plated areas (3), and every two adjacent to-be-plated areas (3) are separated from each other. There are at least two reserved areas (13), and every two adjacent to-be-plated areas (13) are separated from each other.

4. The method for electroplating nickel-gold on a ceramic copper-clad substrate according to claim 1, characterized in that: In step S3, the metal plating layer (4) is a nickel layer or a gold layer. When the metal plating layer (4) is a nickel layer, the thickness of the metal plating layer (4) is 10-20 μm; when the metal plating layer (4) is a gold layer, the thickness of the metal plating layer (4) is 100-200 nm.

5. The method for electroplating nickel-gold on a ceramic copper-clad substrate according to claim 1, characterized in that: There are at least two areas to be plated (3), and every two adjacent areas to be plated (3) are separated from each other.

6. The method for electroplating nickel-gold on a ceramic copper-clad substrate according to claim 1, characterized in that: In step S2, the following steps are sequentially included: Step S2a, covering the complete dry film (5) on the copper surface (1); Step S2b, placing a film (6) having a pattern of a non-plating area (12) between an exposure light source (7) and a dry film (5) on the copper surface (1); Step S2c, performing an exposure operation on the dry film (5), so that the dry film (5) remains in the non-plating area (12) and the area to be plated (3) is exposed.

7. The method for electroplating nickel-gold on a ceramic copper-clad substrate according to claim 1, characterized in that: In the step S5, the following steps are sequentially included: Step S5a, covering the complete dry film (5) on the metal plating layer (4) on the copper surface (1); Step S5b, placing the film (6) including the pattern of the reserved area (13) between the exposure light source (7) and the dry film (5) on the copper surface (1); Step S5c: performing an exposure operation on the dry film (5), so that the dry film (5) remains on the reserved area (13) and the etched area (2) is exposed at the same time.

8. The method for electroplating nickel-gold on a ceramic copper-clad substrate according to claim 7, characterized in that: In the step S5b, in a state where the reserved area (13) completely overlaps with the area to be plated (3), the non-plated area (12) completely overlaps with the etched area (2), and the distance between each two reserved areas (13) is greater than twice the thickness of the metal coating (4), the hollowed-out area of ​​the film (6) used includes a corresponding area (8) corresponding to the shape and size of the area to be plated (3), an expansion area (9) is provided on the outer contour of the corresponding area (8), and a shading block (10) is provided at the angle between each two bent and extended shading areas.

9. The method for electroplating nickel-gold on a ceramic copper-clad substrate according to claim 8, characterized in that: The width of the extended area (9) is equal to the thickness of the metal coating (4), and in a top view of the ceramic substrate (11) during the exposure process, the corresponding area (8) overlaps with the area to be plated (3). After step S5, air is blown toward the dry film (5) so that the area on the dry film (5) corresponding to the extended area (9) is attached to the side wall of the metal coating (4).

10. The method for electroplating nickel-gold on a ceramic copper-clad substrate according to claim 1, characterized in that: In the step S5, the following steps are sequentially included: Step S51, coating each reserved area (13) with a thermoplastic material (14); Step S52: heating the thermoplastic material (14) so ​​that the thermoplastic material (14) covers each outer surface in the reserved area (13) to form a protective film.

Images