Electronic element etching processing method of Kovar alloy coated copper core composite sheet

Abstract

The invention relates to an etching processing method for an electronic element of a Kovar alloy coated copper core composite sheet, and belongs to the field of manufacturing of special electronic materials. The method comprises the following steps: S1, carrying out pretreatment on the surface of a to-be-processed Kovar alloy coated copper core composite sheet; s2, covering the surface of the Kovar alloy coated copper core composite sheet with a photosensitive film; s3, exposing and developing the coated Kovar alloy coated copper core composite sheet, and processing a pattern needing to be etched on the photosensitive film; s4, etching the coating layer Kovar alloy layer by using a selective Kovar alloy etching solution; s5, cleaning and drying; s6, carrying out secondary etching by using a selective copper etching solution; and S7, stripping the film. The electronic element of the Kovar alloy coated copper core composite sheet is processed through a two-step etching method, and compared with punch forming, the phenomena of deformation, burrs, delamination and the like are avoided. A two-step etching method is adopted, the problem that one kind of metal is over-corroded due to the fact that the etching rates of the same kind of etching liquid on the metal made of different materials are different is solved, and the etching factor is greatly improved.

Description

Technical Field

[0001] The present invention relates to the technical field of electronic component processing, and in particular to an electronic component etching processing method of a Kovar alloy-coated copper core composite sheet. Background Art

[0002] Kovar is a low-thermal expansion alloy primarily composed of iron, nickel, and cobalt. Due to its low thermal expansion coefficient and excellent dimensional stability, Kovar is widely used in the electronics industry. Kovar-clad copper core composites, a composite of Kovar and oxygen-free copper, offer excellent conductivity, toughness, and corrosion resistance. They are currently widely used in the power, communications, and automotive industries, generating significant market demand.

[0003] Currently, the primary processing methods for Kovar alloy-clad copper-core composite materials used in electronic components, vacuum devices, magnetoelectric components, and electric heating devices are wire cutting and die punching. Wire cutting is inefficient and costly, making it suitable only for single-piece and small-batch production. While die punching is efficient, it can also produce deformation, burrs, and delamination, resulting in a relatively low yield.

[0004] Metal etching is a technique for removing metal surface material to form patterns or structures through chemical or physical methods. It is mainly divided into wet etching and dry etching. This invention involves wet etching, also known as photochemical etching, which involves removing the protective film of the area to be etched after lamination, exposure, and development. The developed area is exposed to a chemical solution during etching, which dissolves and corrodes the area, creating a hollowed-out effect.

[0005] Etching factor: It is the core parameter to measure the quality of etching process. During the etching process, the etching liquid not only etches in the vertical direction, but also attacks the unprotected metal surfaces on both sides. We call this side etching. Especially in the manufacture of metal precision components, it is defined as: the ratio of etching depth to lateral etching in the metal etching production process. Figure 6 、 Figure 7 Normally, the metal cross-section etched simultaneously on the top and bottom surfaces forms a hexagonal shape, narrow at the top and bottom and wide in the middle. The formula for calculating the etching factor is EF = 2h / (ba). The larger the etching factor, the closer the cross-section is to a rectangle. The process flow and method are key to determining the etching factor. Implementing the right etching process is crucial to ensuring that electronic components meet design precision. Summary of the Invention

[0006] To address these issues, research is underway on the processing technology for Kovar copper-clad electronic components, vacuum devices, magnetoelectric components, and electric heating devices. Photochemical etching offers advantages such as high efficiency, no deformation, no delamination, no burrs, low cost, no mold requirements, and a high yield rate. It is poised to become the mainstream processing method for Kovar copper-clad electronic components in the future.

[0007] The present invention provides a method for etching electronic components using a Kovar alloy-coated copper core composite sheet, aiming to address the technical problems mentioned in the background technology section above. The technical solution of the present invention is as follows: A method for etching electronic components of a Kovar alloy-coated copper core composite sheet, characterized by comprising the following steps: S1: Pre-treating the surface of the Kovar alloy-coated copper core composite sheet to be processed; S2: Laminating the surface of the Kovar alloy-coated copper core composite sheet; S3: Expose and develop the coated Kovar alloy-coated copper core composite sheet to produce the electronic component pattern to be etched on the photosensitive film; S4: using a Kovar alloy selective etching solution to perform a first etching on the developed cladding layer Kovar alloy layer to obtain a primary etched sheet of a primary etched groove; S5: Clean and dry the initially etched sheet; S6: etching the copper core layer of the initially etched sheet for a second time using a copper selective etching solution; S7: Stripping the film to obtain the target Kovar alloy-coated copper core electronic component.

[0008] Steps S4, S5, and S6 are completed in a continuous etching device comprising a first etching chamber, a cleaning and drying chamber, a second etching chamber, a first material feeding mechanism, a second material feeding mechanism, a position limiting device, a first etching spray mechanism, a second etching spray mechanism, a cleaning spray mechanism, and an air drying mechanism.

[0009] Preferably, the Kovar alloy-clad copper core composite sheet comprises a copper core layer and two Kovar alloy layers, and the copper core layer is located between the two Kovar alloy layers.

[0010] Preferably, the thickness of the Kovar alloy-clad copper core composite sheet is 0.1 mm to 2.0 mm.

[0011] Preferably, the surface of the Kovar alloy-coated copper core composite sheet to be processed in S1 is pre-treated by using acid or alkali to wash away oil stains on the surface of the metal thin material coil, so that the surface tension coefficient of the Kovar alloy-coated copper core composite sheet is greater than or equal to 32 dynes.

[0012] Preferably, in S2, a film is applied to the surface of the Kovar alloy-coated copper core composite sheet, and the film is applied to both the upper and lower surfaces simultaneously, and the film includes a dry film and a wet film.

[0013] The Kovar alloy-coated copper core composite sheet has a thickness of 0.3mm or less when applied as a dry film, and a thickness of more than 0.3mm when applied as a wet film. The drying temperature of the dry and wet films is 60-120°C.

[0014] The exposure, development, etching and film stripping are all performed simultaneously on the upper and lower surfaces.

[0015] Preferably, the exposure time of the film-coated Kovar alloy-coated copper core composite sheet in S3 is 3-15s, and the exposure energy is 10-130mj / cm 2 ; The development uses Na2CO3 solution as a developer to develop the Kovar alloy-coated copper core composite sheet, the concentration of the Na2CO3 solution is 1.5-6.0%, the development temperature is 20-50°C, and the development time is 20-60s; the electronic component patterns to be etched on the photosensitive film are formed simultaneously on the upper and lower surfaces, and the electronic component patterns on the upper and lower surfaces correspond to each other.

[0016] Preferably, in S4, the cladding layer Kovar alloy layer is first etched using a Kovar alloy etching solution. The etching solution is a Kovar alloy selective etching solution that does not corrode or only slightly etch copper. The first etching location is located on the surface of the copper core metal layer.

[0017] Preferably, in S6, the copper core layer is etched for a second time using an etching solution until the finished product is obtained. The etching solution is a copper selective etching solution that does not corrode or slightly etch the Kovar alloy.

[0018] Preferably, steps S4, S5 and S6 are performed in a continuous etching device, which includes a first etching chamber, a cleaning and drying chamber, a second etching chamber, a first material feeding mechanism, a second material feeding mechanism, a first etching spray mechanism, a second etching spray mechanism, a cleaning spray mechanism, an air drying mechanism and a limiting device.

[0019] The first and second etching spray mechanisms both spray and etch the composite sheet simultaneously. The spray etching pressures are: the upper spray pressure is 0.2-2.2 Pa, and the lower spray pressure is 0.1-2 Pa. The lower spray pressure P2 is always lower than the upper spray pressure P1.

[0020] The transmission speed V1 of the first material transmission mechanism is less than or equal to the transmission speed V2 of the second material transmission mechanism; the transmission speeds of V1 and V2 are 0.1-4 m / min.

[0021] Preferably, in S5, the cleaning and drying are carried out by spraying water from top to bottom, with a spray pressure of 0.5-1.5 kg / cm 2 Cleaning time 10-30s; the drying, use filtered compressed air to dry the surface water stains of the Kovar alloy coated copper core composite sheet, the gas pressure is 1.0-3.0 kg / cm 2 , compressed air temperature is 20-40℃.

[0022] Beneficial effects of the present invention: 1. Currently, the main processing methods for Kovar alloy-coated copper core composite materials used in electronic components, electronic vacuum devices, magnetoelectric components, electric heating devices, etc. are wire cutting and die punching. The wire cutting processing method has low efficiency, high cost, will produce burrs and thermal deformation, and is only suitable for single-piece and small-batch production. Although the die punching processing method is highly efficient, the processed products will produce deformation, burrs, delamination and other phenomena, resulting in a relatively low yield. The present invention processes electronic components of Kovar alloy-coated copper core composite sheets by photochemical etching. Compared with stamping molding, it will not produce deformation, burrs, delamination and other phenomena, thereby improving the yield. Compared with wire cutting, it will not produce thermal deformation and burrs, and the efficiency is improved by more than ten times, or even dozens of times.

[0023] 2. The present invention uses a Kovar alloy selective etching solution and a copper selective etching solution, and utilizes a secondary etching method to effectively solve the problem of different etching rates of the same etching solution on different metal materials, which causes excessive corrosion of one metal. It can significantly improve the etching factor and thus improve product precision. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a flowchart of the overall implementation steps of a method for etching electronic components of a Kovar alloy-coated copper core composite sheet according to an embodiment of the present invention; Figure 2 It is a schematic front cross-sectional view of a processing device for two consecutive etchings (first etching and second etching); Figure 3 A top view of the material feeding mechanism of the device for two consecutive etchings (the first etching and the second etching); Figure 4 Schematic diagram of the cross section of Kovar alloy-coated copper core composite sheet; Figure 5 A schematic cross-sectional view of a Kovar alloy-clad copper core composite sheet coated or laminated with photosensitive films on top and bottom; Figure 6 This is a schematic diagram of the cross-sectional shape of the Kovar alloy-coated copper core composite material after exposure and development; Figure 7 A schematic cross-sectional view of a Kovar alloy layer after etching using one etching solution in one etching process; Figure 8 A cross-sectional schematic diagram of the etching process of the Kovar alloy layer and the copper core layer using one etching solution in one etching process; Figure 9 A schematic diagram of the cross-section of the Kovar layer after the first etching using a Kovar-selective etching solution using a two-step etching process; Figure 10 This is a schematic cross-sectional view of the Kovar alloy layer and the copper core layer after the second etching with a copper-selective etching solution using a two-step etching process; Figure 11 Schematic diagram for calculating etching factor after one etching process; Figure 12 Schematic diagram for calculating etching factor after two etching processes; Figure 13 Schematic diagram of the finished Kovar alloy-coated copper core electronic component after film stripping.

[0025] In the figure, 1: the chamber of the double etching device, 11: the first etching chamber, 111: the upper spray mechanism of the first etching liquid, 112: the lower spray mechanism of the first etching liquid, 12: the cleaning and drying chamber, 121: the lower spray mechanism of cleaning, 122: the upper spray mechanism of cleaning, 13: the second etching chamber, 131: the lower spray mechanism of the second etching, 132: the upper spray mechanism of the second etching; 2: Kovar alloy-coated copper core composite material coated or laminated with a photosensitive film and developed, 21: upper Kovar alloy layer, 22: copper core layer, 23: lower Kovar alloy layer, 24: upper photosensitive film layer, 25: lower photosensitive film layer, 26: etching removal area after development, 27: side shape of Kovar alloy layer removed by single etching method, 28: etching groove of single etching method, 29: side shape of Kovar alloy and copper core layer removed by single etching method, 30: through-section of single etching method, 31: side shape of Kovar alloy layer removed, 32: primary etching groove, 33: side shape of Kovar alloy and copper core layer removed, 34: primary etching through groove; 3: Air drying mechanism; 4: First etching, cleaning, and drying of the conveyor device; 5: Second etching conveyor; 6: Limit device. DETAILED DESCRIPTION

[0026] Example 1 The copper core composite sheet with a thickness of 0.3mm is clad with Kovar alloy. Figure 4 ), using dry photosensitive film for etching of electronic components.

[0027] like Figure 1As shown, a method for etching electronic components of a Kovar alloy-coated copper core composite sheet comprises: S1: Kovar alloy coated copper core composite sheet to be processed ( Figure 4 The upper surface of the upper Kovar alloy layer 21 and the lower surface of the lower Kovar alloy layer 23 are pretreated. Surface oil stains are cleaned with acid or alkali to ensure that the surface tension coefficient of the Kovar alloy-coated copper core composite sheet is greater than or equal to 32 dynes.

[0028] S2: Copper core composite sheet clad in Kovar alloy Figure 4 The upper and lower surfaces of the film are respectively attached to the upper photosensitive film layer 24 and the lower photosensitive film layer 25. The film is dried in a drying oven at 60-120°C.

[0029] S3: The coated Kovar alloy-coated copper core composite sheet is exposed and developed to form the electronic component pattern to be etched on the photosensitive film, and the post-development etching removal areas 26 are formed on the upper photosensitive film layer 24 and the lower photosensitive film layer 25 respectively.

[0030] The specific steps of S3 include: S301: Exposure: The exposure time of the film-coated Kovar alloy-coated copper core composite sheet is 3-15s, and the exposure energy is 10-130mj / cm 2 ; S302: Development: Use Na2CO3 solution as a developer to develop the Kovar alloy-coated copper core composite sheet. The concentration of the Na2CO3 solution is 6.0%, the development temperature is 50°C, and the development time is 20s. The electronic component patterns to be etched are processed on the photosensitive film so that they are formed simultaneously on the upper and lower surfaces, and the electronic component patterns on the upper and lower surfaces correspond to each other.

[0031] S4: Using a selective etching solution for Kovar alloy, the developed coating Kovar alloy layer, i.e., the upper Kovar alloy layer 21 and the lower Kovar alloy layer 23, is etched for the first time to obtain a primary etching sheet with a primary etching groove 32. Figure 9 , the primary etching groove 32 shows the side shape 31 of the removed Kovar alloy layer.

[0032] .S5: Clean and dry the initially etched sheet.

[0033] S6: Use copper selective etching solution to etch the copper core layer of the initial etched sheet for the second time, and the etching is completed ( Figure 10 ), forming a primary etched through groove 34, in which the side shape 33 of the Kovar alloy and the copper core layer is removed.

[0034] S7: Strip the film to obtain the target Kovar alloy-coated copper core electronic components ( Figure 13 ).

[0035] Steps S4, S5, and S6 are performed in a continuous etching device ( Figure 2 The continuous etching device includes a first etching chamber 11, a cleaning and drying chamber 12, a second etching chamber 13, a first material feeding mechanism, a second material feeding mechanism, a limiting device 6, a first etching liquid upper spray mechanism 111, a first etching liquid lower spray mechanism 112, a cleaning lower spray mechanism 121, a cleaning upper spray mechanism 122, an air drying mechanism 3, a second etching lower spray mechanism 131, and a second etching upper spray mechanism 132; The first etching chamber 11, the cleaning and drying chamber 12, and the second etching chamber 13 are sequentially distributed according to the material conveying direction and together constitute the double etching device chamber 1; the first etching chamber 11, the cleaning and drying chamber 12, and the second etching chamber 13 are spaced apart from each other and connected by a material conveying channel; The first etching liquid upper spray mechanism 111 and the first etching liquid lower spray mechanism 112 constitute a first etching spray mechanism; the cleaning lower spray mechanism 121 and the cleaning upper spray mechanism 122 constitute a cleaning spray mechanism; the second etching lower spray mechanism 131 and the second etching upper spray mechanism 132 constitute a second etching spray mechanism; The first material feeding mechanism refers to the first etching, cleaning, and drying conveying device 4, which includes a plurality of horizontally evenly arranged conveying rollers distributed in the first etching chamber 11 and the cleaning and drying chamber 12; the second material feeding mechanism refers to the second etching conveying device 5, which includes a plurality of horizontally evenly arranged conveying rollers distributed in the second etching chamber 13; In the first etching chamber 11, the material runs on the conveying roller of the first material conveying mechanism, and a limiting device 6 is provided on the conveying roller. A first etching liquid upper spraying mechanism 111 and a first etching liquid lower spraying mechanism 112 are respectively provided above and below the conveying roller; In the cleaning and drying chamber 12, an upper cleaning spray mechanism 122 and a lower cleaning spray mechanism 121 are respectively provided above and below the conveying roller; an air drying mechanism 3 is provided at the rear of the conveying roller; Similarly, in the second etching chamber 13, the material runs on the conveying roller of the second material feeding mechanism, and a limiting device 6 is provided on the conveying roller. A second etching upper spray mechanism 132 and a second etching lower spray mechanism 131 are respectively provided above and below the conveying roller.

[0036] In the embodiment, the Kovar alloy-clad copper core composite sheet includes a copper core layer 22 and two Kovar alloy layers, and the copper core layer 22 is located between the two Kovar alloy layers.

[0037] In the embodiment, the exposure time of the film-coated Kovar alloy-coated copper core composite sheet in S3 is 3-15s, and the exposure energy is 10-130mj / cm 2; The development uses Na2CO3 solution as a developer to develop the Kovar alloy-coated copper core composite sheet, the concentration of the Na2CO3 solution is 1.5-6.0%, the development temperature is 20-50°C, and the development time is 20-60s; the electronic component patterns to be etched on the photosensitive film are formed simultaneously on the upper and lower surfaces, and the electronic component patterns on the upper and lower surfaces correspond to each other.

[0038] In the embodiment, in S4, a Kovar etchant is used to perform a first etching of the cladding Kovar layers, i.e., the upper Kovar layer 21 and the lower Kovar layer 23. The etchant is Kovar-selective and does not corrode or only slightly etch copper. The first etching is performed on the surface of the copper core layer.

[0039] In the embodiment, in S6, the copper core layer is etched for the second time using an etching solution until the finished product is obtained. The etching solution is a copper selective etching solution that does not corrode or only slightly corrodes the Kovar alloy.

[0040] In this embodiment, the first and second etching spray mechanisms both employ a simultaneous upper and lower spraying method to spray-etch the composite sheet. The spray etching pressures are: the upper spray pressure is 0.2-2.2 Pa, and the lower spray pressure is 0.1-2 Pa. The lower spray pressure P2 is always less than the upper spray pressure P1.

[0041] In the embodiment, the transmission speed V1 of the first material transmission mechanism is always less than or equal to the transmission speed V2 of the second material transmission mechanism; the transmission speeds of V1 and V2 are 0.1-4 m / min.

[0042] In the embodiment, the cleaning and drying in S5 are carried out by spraying water from top to bottom, with a spray pressure of 0.5-1.5 kg / cm 2 Cleaning time 10-30s; the drying, use filtered compressed air to dry the surface water stains of the Kovar alloy coated copper core composite sheet, the gas pressure is 1.0-3.0kg / cm 2 , compressed air temperature is 20-40℃.

[0043] Example 2 The copper core composite sheet with a thickness of 0.6mm is clad with Kovar alloy. Figure 4 ), using wet photosensitive film for etching of electronic components.

[0044] like Figure 1 As shown, a method for etching electronic components of a Kovar alloy-coated copper core composite sheet comprises: S1: Kovar alloy coated copper core composite sheet to be processed ( Figure 4The upper surface of the upper Kovar alloy layer 21 and the lower surface of the lower Kovar alloy layer 23 are pretreated. Surface oil stains are cleaned with acid or alkali to ensure that the surface tension coefficient of the Kovar alloy-coated copper core composite sheet is greater than or equal to 32 dynes.

[0045] S2: Copper core composite sheet clad in Kovar alloy Figure 4 The upper and lower surfaces of the film are respectively attached to the upper photosensitive film layer 24 and the lower photosensitive film layer 25. The film is dried in a drying oven at 60-120°C.

[0046] S3: The coated Kovar alloy-coated copper core composite sheet is exposed and developed to form the electronic component pattern to be etched on the photosensitive film, and the post-development etching removal areas 26 are formed on the upper photosensitive film layer 24 and the lower photosensitive film layer 25 respectively.

[0047] The specific steps of S3 include: S301: Exposure: The exposure time of the film-coated Kovar alloy-coated copper core composite sheet is 3-15s, and the exposure energy is 10-130mj / cm 2 ; S302: Development: Use Na2CO3 solution as a developer to develop the Kovar alloy-coated copper core composite sheet. The concentration of the Na2CO3 solution is 6.0%, the development temperature is 50°C, and the development time is 20s. The electronic component patterns to be etched are processed on the photosensitive film so that they are formed simultaneously on the upper and lower surfaces, and the electronic component patterns on the upper and lower surfaces correspond to each other.

[0048] S4: Using a selective etching solution for Kovar alloy, the developed coating Kovar alloy layer, i.e., the upper Kovar alloy layer 21 and the lower Kovar alloy layer 23, is etched for the first time to obtain a primary etching sheet with a primary etching groove 32. Figure 9 , the primary etching groove 32 shows the side shape 31 of the removed Kovar alloy layer.

[0049] S5: Clean and dry the initially etched sheet.

[0050] S6: Use copper selective etching solution to etch the copper core layer of the initial etched sheet for the second time, and the etching is completed ( Figure 10 ), forming a primary etched through groove 34, in which the side shape 33 of the Kovar alloy and the copper core layer is removed.

[0051] Steps S4, S5, and S6 are performed in a continuous etching device ( Figure 2The continuous etching device includes a first etching chamber 11, a cleaning and drying chamber 12, a second etching chamber 13, a first material feeding mechanism, a second material feeding mechanism, a limiting device 6, a first etching liquid upper spray mechanism 111, a first etching liquid lower spray mechanism 112, a cleaning lower spray mechanism 121, a cleaning upper spray mechanism 122, an air drying mechanism 3, a second etching lower spray mechanism 131, and a second etching upper spray mechanism 132; The first etching chamber 11, the cleaning and drying chamber 12, and the second etching chamber 13 are sequentially distributed according to the material conveying direction and together constitute the double etching device chamber 1; the first etching chamber 11, the cleaning and drying chamber 12, and the second etching chamber 13 are spaced apart from each other and connected by a material conveying channel; The first etching liquid upper spray mechanism 111 and the first etching liquid lower spray mechanism 112 constitute a first etching spray mechanism; the cleaning lower spray mechanism 121 and the cleaning upper spray mechanism 122 constitute a cleaning spray mechanism; the second etching lower spray mechanism 131 and the second etching upper spray mechanism 132 constitute a second etching spray mechanism; The first material feeding mechanism refers to the first etching, cleaning, and drying conveying device 4, which includes a plurality of horizontally evenly arranged conveying rollers distributed in the first etching chamber 11 and the cleaning and drying chamber 12; the second material feeding mechanism refers to the second etching conveying device 5, which includes a plurality of horizontally evenly arranged conveying rollers distributed in the second etching chamber 13; S7: Strip the film to obtain the target Kovar alloy-coated copper core electronic components ( Figure 13 ).

[0052] In an embodiment, the Kovar alloy-clad copper core composite sheet includes a copper core layer and two Kovar alloy layers, and the copper core layer is located between the two Kovar alloy layers.

[0053] In the embodiment, the exposure time of the film-coated Kovar alloy-coated copper core composite sheet in S3 is 3-15s, and the exposure energy is 10-130mj / cm 2 ; The development uses Na2CO3 solution as a developer to develop the Kovar alloy-coated copper core composite sheet, the concentration of the Na2CO3 solution is 1.5-6.0%, the development temperature is 20-50°C, and the development time is 20-60s; the electronic component patterns to be etched on the photosensitive film are formed simultaneously on the upper and lower surfaces, and the electronic component patterns on the upper and lower surfaces correspond to each other.

[0054] In the embodiment, in S4, a Kovar etchant is used to perform a first etching of the cladding Kovar layers, i.e., the upper Kovar layer 21 and the lower Kovar layer 23. The etchant is Kovar-selective and does not corrode or only slightly etch copper. The first etching is performed on the surface of the copper core layer.

[0055] In the embodiment, in S6, the copper core layer is etched for the second time using an etching solution until the finished product is obtained. The etching solution is a copper selective etching solution that does not corrode or only slightly corrodes the Kovar alloy.

[0056] In this embodiment, the first and second etching spray mechanisms both employ a simultaneous upper and lower spraying method to spray-etch the composite sheet. The spray etching pressures are: the upper spray pressure is 0.2-2.2 Pa, and the lower spray pressure is 0.1-2 Pa. The lower spray pressure P2 is always less than the upper spray pressure P1.

[0057] In the embodiment, the transmission speed V1 of the first material transmission mechanism is always less than or equal to the transmission speed V2 of the second material transmission mechanism; the transmission speeds of V1 and V2 are 0.1-4 m / min.

[0058] In the embodiment, the cleaning and drying in S5 are carried out by spraying water from top to bottom, with a spray pressure of 0.5-1.5 kg / cm 2 Cleaning time 10-30s; the drying, use filtered compressed air to dry the surface water stains of the Kovar alloy coated copper core composite sheet, the gas pressure is 1.0-3.0 kg / cm 2 , compressed air temperature is 20-40℃.

[0059] Comparative Example A dual-purpose etching solution for Kovar alloy and copper is used, which can not only meet the requirements of Kovar alloy etching but also achieve copper etching. The material thickness is selected to be the same as that of Example 1 and Example 2. The Kovar alloy-coated copper core composite sheet is etched using a traditional one-time process.

[0060] After the etching of the Kovar alloy layer is completed, an etching groove 28 ( Figure 7 ), the etching groove 28 of the one-step etching method shows the side shape 27 of the Kovar alloy layer removed by the one-step etching method, and the through section 30 of the one-step etching method is formed after the copper core layer is etched. Figure 8 ), a through section 30 of a single etch process shows the removal of the Kovar alloy and the copper core layer side profile 29 by a single etch process.

[0061] Using a Kovar alloy and copper etching solution, the calculation formula for the etching factor of the component processed by a one-time etching process is EF1=2h / (b1-a1)( Figure 11 ) Using two selective etching solutions of Kovar alloy and copper, and using a two-step etching process, the calculation formula for the etching factor of the component is EF2=2h / (b2-a2) ( Figure 12 ) Depend on Figure 11and Figure 12 It can be seen that the etching factor EF2 of the component processed by the double etching method is significantly improved compared with the etching factor EF1 of the component processed by the single etching method.

Claims

1. A method for etching electronic components of Kovar alloy-coated copper core composite sheets, characterized in that: The following steps are involved: S1: Pre-treating the surface of the Kovar alloy-coated copper core composite sheet to be processed; S2: Laminating the surface of the Kovar alloy-coated copper core composite sheet; S3: Expose and develop the coated Kovar alloy-coated copper core composite sheet to produce the electronic component pattern to be etched on the photosensitive film; S4: using a Kovar alloy selective etching solution to perform a first etching on the developed cladding layer Kovar alloy layer to obtain a primary etched sheet of a primary etched groove; S5: Clean and dry the initially etched sheet; S6: etching the copper core layer of the initially etched sheet for a second time using a copper selective etching solution; S7: Stripping the film to obtain the target Kovar alloy-coated copper core electronic component.

2. The method for etching electronic components of a Kovar alloy-coated copper core composite sheet according to claim 1, characterized in that The Kovar alloy-clad copper core composite sheet comprises a copper core layer and two Kovar alloy layers, and the copper core layer is located between the two Kovar alloy layers.

3. The method for etching electronic components of a Kovar alloy-coated copper core composite sheet according to claim 1, characterized in that The thickness of the Kovar alloy-clad copper core composite sheet is 0.1mm-2.0mm.

4. The method for etching electronic components of a Kovar alloy-coated copper core composite sheet according to claim 1, characterized in that In S1, the surface of the Kovar alloy-coated copper core composite sheet to be processed is pre-treated by using acid or alkali to remove oil stains on the surface of the metal thin material coil, so that the surface tension coefficient of the Kovar alloy-coated copper core composite sheet is greater than or equal to 32 dynes.

5. The method for etching electronic components of a Kovar alloy-coated copper core composite sheet according to claim 1, characterized in that In S2, a film is applied to the surface of the Kovar alloy-coated copper core composite sheet, wherein the film is applied to the upper and lower surfaces simultaneously, and the film includes a dry film and a wet film; The Kovar alloy-coated copper core composite sheet has a thickness of less than or equal to 0.3 mm for dry film application and a thickness of more than 0.3 mm for wet film application; the drying temperature of the dry and wet films is 60-120°C; The exposure, development, etching and film stripping are all performed simultaneously on the upper and lower surfaces.

6. The method for etching electronic components of a Kovar alloy-coated copper core composite sheet according to claim 1, characterized in that The exposure time of the film-coated Kovar alloy-coated copper core composite sheet in S3 is 3-15s, and the exposure energy is 10-130mj / cm 2 ; The development uses Na2CO3 solution as a developer to develop the Kovar alloy-coated copper core composite sheet, the concentration of the Na2CO3 solution is 1.5-6.0%, the development temperature is 20-50°C, and the development time is 20-60s; the electronic component patterns to be etched on the photosensitive film are formed simultaneously on the upper and lower surfaces, and the electronic component patterns on the upper and lower surfaces correspond to each other.

7. The method for etching electronic components of a Kovar alloy-coated copper core composite sheet according to claim 1, characterized in that In S4, the cladding layer Kovar alloy layer is etched for the first time using a Kovar alloy selective etching solution, and the first etching position is located on the surface of the copper core layer.

8. The method for etching electronic components of a Kovar alloy-coated copper core composite sheet according to claim 1, characterized in that In S6, the copper core layer is etched for a second time using a copper selective etching solution until the finished product is obtained. The copper selective etching solution has no corrosion or only slightly corrodes the Kovar alloy.

9. The method for etching electronic components of a Kovar alloy-coated copper core composite sheet according to claim 1, characterized in that Steps S4, S5, and S6 are performed in a continuous etching device, which includes a first etching chamber, a cleaning and drying chamber, a second etching chamber, a first material feeding mechanism, a second material feeding mechanism, a first etching spray mechanism, a second etching spray mechanism, a cleaning spray mechanism, an air drying mechanism, and a limiting device; The first etching spray mechanism and the second etching spray mechanism both adopt a top and bottom simultaneous spraying method to spray-etch the composite sheet; the spray etching pressure is: the upper spray pressure is: 0.2-2.2Pa, the lower spray pressure is 0.1-2Pa, and the lower spray pressure P2 is always less than the upper spray pressure P1; The transmission speed V1 of the first material transmission mechanism is less than or equal to the transmission speed V2 of the second material transmission mechanism; the transmission speeds of V1 and V2 are 0.1-4 m / min.

10. The electronic component etching processing method of the Kovar alloy-coated copper core composite sheet according to claim 1, characterized in that: The cleaning described in S5 is carried out by spraying water from top to bottom, with a spray pressure of 0.5-1.5kg / cm 2 , cleaning time 10-30s; the drying, use filtered compressed air to dry the surface water stains of the Kovar alloy coated copper core composite sheet, the gas pressure is 1.0-3.0 kg / cm 2 , compressed air temperature is 20-40℃.

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