Preparation method of chemical nickel-palladium-gold plating of high-temperature co-fired ceramic packaging shell
Through the method of chemical nickel plating gold, the problem of high -temperature co -burning ceramic packaging shells after chemical sinking pad pads and black dish effects, realizing the effect of improving durability and welding, and reducing the thickness and manufacturing cost of the plating layer and the cost of manufacturing costs. Essence
Patent Information
- Application Number
- CN202411491765.X
- Authority / Receiving Office
- CN · China
- Patent Type
- Applications(China)
- Current Assignee / Owner
- Filing Date
- 2024-10-24
- Publication Date
- 2025-01-24
AI Technical Summary
The high-temperature co-fired ceramic packaging shell is prone to black disk effect of the pad after chemical deposits of gold, affecting the bonding and welding reliability.
The method of chemical nickel -plating gold gold is adopted, and the nickel layer is formed as a protective layer, a pupa layer as a resistance layer and gold layer as a performance layer by removing oil, pickling, activating, chemical nickel plating, nickel plating, and gold.
It solves the problem of pad black pad effect, improves the durability and solderability of the ceramic package shell, while reducing the thickness of the plating layer, reducing the use of precious metals and manufacturing costs.
Smart Images
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Abstract
Description
Technical Field
[0001] The invention relates to a method for chemically plating on a ceramic shell, in particular to a method for preparing a chemically plated nickel-palladium-gold of a high-temperature co-fired ceramic packaging shell. Background Art
[0002] In the field of electronic packaging, the package shell is exposed to different environmental conditions during actual use, such as high temperature, humidity, acid-base atmosphere, oxygen, etc. When pursuing excellent properties such as high thermal conductivity and good electrical conductivity, ceramic package shells usually use different metal materials, such as iron-nickel alloy, oxygen-free copper, tungsten-copper alloy, etc. Some metal materials themselves are not corrosion-resistant or their performance does not meet the use requirements. Therefore, in the manufacturing process of high-temperature co-fired ceramic (HTCC) package shells, surface treatment is usually required to improve their corrosion resistance, conductivity, welding performance and maintain a specific appearance. Plating, as a method of surface treatment, is widely used in ceramic electronic packaging.
[0003] In the traditional packaging shell plating process, electrochemical deposition is generally used to plate nickel and gold layers on the metal parts. This not only requires the metal parts of the shell to maintain electrical connectivity with each other, but also makes it impossible to finely control the thickness of the plating. Generally, the plating thickness range is large, with the nickel layer thickness of 1.3 to 8.9 μm and the gold layer thickness of 1.3 to 5.7 μm.
[0004] In recent years, a large number of advanced packages such as SIP have been involved in the HTCC packaging field. The SIP package shell is a typical product with a large number of isolated islands, which is almost impossible to plate using conventional electroplating methods. The more effective plating technology at this stage is chemical deposition nickel-gold plating. However, the pads treated by the chemical deposition nickel-gold process are prone to black pad effect, which affects the reliability of bonding and welding. Therefore, a plating solution that can be applied to high-temperature co-fired ceramic package shells is urgently needed to solve the above problems. Summary of the invention
[0005] Purpose of the invention: The purpose of the present invention is to provide a method for preparing chemical nickel-palladium-gold plating of a high-temperature co-fired ceramic packaging shell, which can solve the black pad effect of the pad after chemical gold plating of the high-temperature co-fired ceramic packaging shell.
[0006] Technical solution: The method for preparing the chemical nickel-palladium-gold plating of the high-temperature co-fired ceramic packaging shell of the present invention comprises the following steps:
[0007] (1) Degreasing, pickling and activating the high temperature co-fired ceramic package shell;
[0008] (2) chemically nickel-plating the high-temperature co-fired ceramic package shell treated in step (1), wherein the nickel layer is combined with the substrate to form a protective layer, and then the chemical nickel solution is removed by washing;
[0009] (3) chemically plating palladium on the high temperature co-fired ceramic package shell treated in step (2) to form a palladium barrier layer on the chemical nickel layer, and then washing to remove the chemical palladium solution;
[0010] (4) chemically gold-plating the high-temperature co-fired ceramic package shell after the treatment in step (3) to form a gold performance layer, then cleaning to remove the chemical gold solution, and drying to obtain a high-temperature co-fired ceramic package shell with a surface plated with chemical nickel-palladium-gold.
[0011] The degreasing process in step (1) is as follows: placing the high temperature co-fired ceramic package shell into a degreasing agent for degreasing, and then cleaning and removing the degreasing agent; the degreasing agent is an alkaline degreasing agent, the use temperature of the alkaline degreasing agent is 65 to 75° C., and the processing time is 5 to 15 minutes.
[0012] The pickling process in step (1) is as follows: pickling and decontaminating the deoiled high-temperature co-fired ceramic package shell, and then cleaning and removing the acid solution; the pickling temperature is 60-70° C., and the treatment time is 2-3 minutes.
[0013] The activation process in step (1) is as follows: the high temperature co-fired ceramic package shell after acid washing is activated with hydrochloric acid to remove the surface oxide layer, and then the hydrochloric acid solution is washed away.
[0014] The pickling solution used in the pickling in step (1) comprises: 75-100 ml / L sulfuric acid, 5-10 g / L thiourea, and 10-20 ml / L emulsifier; the main component of the emulsifier is OP-10, i.e., alkylphenol polyoxyethylene ether-10.
[0015] The high-temperature co-fired ceramic package shell is usually made of high-temperature co-fired ceramics and various metal parts welded at high temperature. Fine metal burrs adhere to the surface of the metal parts, and the burrs are easy to form coating particles. Therefore, during the pre-treatment process of the high-temperature co-fired ceramic package shell, it is necessary to use a pickling solution to remove the metal burrs. Adding thiourea and emulsifier components to the pickling solution can reduce the corrosion of the acid on the metal substrate of the high-temperature co-fired ceramic package shell, enhance the wetting effect of the substrate and the aqueous solution, and play a role in cleaning metal debris contamination without damaging the metal substrate of the shell. Therefore, when using the pickling solution for treatment, the pickling solution can peel off the fine metal burrs on the substrate, achieve the effect of removing metal burrs, enhance the wetting effect of the solution, and improve the quality of the coating.
[0016] The activation solution used in step (1) is hydrochloric acid with a volume fraction of 45% to 55%, the activation temperature is 35 to 45° C., and the use time is 2 to 3 minutes.
[0017] Wherein, the chemical nickel plating in step (2) uses a medium-phosphorus chemical nickel system, the chemical nickel plating temperature is 77-83° C., the nickel ion concentration is 4.2-4.6 g / L, the pH is 4.6-4.9, and the time is 20-30 min.
[0018] Wherein, the chemical palladium plating solution in step (3) uses a reduced palladium system, the chemical palladium plating temperature is 60-65° C., the palladium ion concentration is 1.5-2.5 g / L, the pH is 6.0-7.0, and the time is 5-10 min.
[0019] Wherein, the chemical gold plating solution in step (4) uses a replacement gold system, the chemical gold plating temperature is 80-85° C., the gold ion concentration is 1.5-3.0 g / L, the pH is 6.0-7.0, and the time is 10-15 min.
[0020] The thickness of the nickel layer is 3.0-5.0 μm; the thickness of the palladium barrier layer is 0.05-0.20 μm; and the thickness of the gold performance layer is 0.05-0.20 μm.
[0021] Beneficial effects: Compared with the prior art, the present invention achieves the following significant effects:
[0022] (1) In the chemical nickel-palladium-gold plating method of the present plating method, the nickel plating layer serves as a protective layer, the palladium plating layer serves as a barrier layer, and the gold plating layer serves as a performance layer, which can solve the black pad effect of the solder pad after the high-temperature co-fired ceramic package shell adopts chemical gold deposition. (2) In the chemical nickel-palladium-gold plating, the thickness of the nickel layer is 3.0-5.0 μm, the thickness of the palladium layer is 0.05-0.20 μm, and the thickness of the gold layer is 0.05-0.20 μm, which ensures that the ceramic package shell has good durability and solderability while reducing the thickness of the plating layer, effectively reducing the use of precious metals and reducing the plating manufacturing cost. (3) The present plating method uses chemical deposition instead of electroplating throughout the process, which reduces energy consumption and carbon emissions. (4) The present invention provides a formula and use method of a pickling solution, which can remove metal burrs, is not easy to corrode the metal substrate, and ensures the quality of the plating. (5) The coating on the surface of the high-temperature co-fired ceramic package shell obtained by the plating method has a good appearance, and after the coating obtained by the plating method is tested at 420°C and N2, the coating still does not peel or bubble, and has good bonding strength. (6) The plating method innovatively develops a chemical nickel-palladium-gold plating process suitable for semiconductor high-temperature co-fired ceramic package shells, which is suitable for the plating manufacturing process of SIP-type non-electrically connected ceramic shells in high-temperature co-fired ceramic package shells. BRIEF DESCRIPTION OF THE DRAWINGS
[0023] Figure 1 This is a real picture of the sample prepared during the plating process of Example 1;
[0024] Figure 2This is a real picture of the sample prepared during the plating process of Example 2;
[0025] Figure 3 This is a real picture of the sample prepared during the plating process of Comparative Example 1. DETAILED DESCRIPTION
[0026] The present invention is described in further detail below.
[0027] Example 1
[0028] The present embodiment provides a method for coating chemical nickel-palladium-gold on a high-temperature co-fired ceramic package shell. The high-temperature co-fired ceramic package shell is assembled into a semi-finished product by high-temperature brazing of a high-temperature co-fired ceramic substrate and metal parts.
[0029] The specific plating method comprises the following steps:
[0030] (1) Alkaline ultrasonic degreasing: In this embodiment, the alkaline degreasing agent selected is a commercially available alkaline degreasing agent, and ultrasonic cleaning is performed at 70°C for 10 minutes to remove mineral oil stains caused by mechanical processing on the surface of the high-temperature co-fired ceramic package shell; then, tap water is used for ultrasonic cleaning at room temperature for 2 minutes to clean the degreasing agent remaining on the surface of the shell; then, pure water is used for ultrasonic cleaning at room temperature for 2 minutes to remove the remaining degreasing agent.
[0031] (2) Pickling: In this embodiment, the pickling solution components are: 80 ml / L sulfuric acid, 10 g / L thiourea, and 10 ml / L emulsifier. The emulsifier is alkylphenol polyoxyethylene ether-10. The high-temperature co-fired ceramic package shell treated in step (1) is placed in the pickling solution and soaked at 65°C for 3 minutes, then ultrasonically cleaned with tap water at room temperature for 2 minutes to remove the residual pickling solution, and then cleaned with pure water at room temperature for 2 minutes.
[0032] (3) Activation with hydrochloric acid: the high temperature co-fired ceramic package shell treated in step (2) is activated with 50% by volume hydrochloric acid at 40° C. for 3 min to remove the oxide layer on the surface of the material, activate the surface of the base metal, and improve the bonding strength of the coating; after activation, it is first washed with pure water at room temperature for 20 seconds, and then washed with pure water at room temperature for 20 seconds to remove the residual hydrochloric acid solution.
[0033] (4) Chemical nickel plating. In this embodiment, the chemical nickel plating uses a medium-phosphorus chemical nickel system, and the phosphorus content of the plating layer is 10%; the high-temperature co-fired ceramic packaging shell treated in step (3) is placed in a chemical nickel plating solution, the nickel plating solution temperature is 80°C, the pH is 4.70, and the nickel plating time is 28 minutes. A chemical nickel layer is obtained by plating. After the chemical nickel plating is completed, it is first rinsed with a first pure water for 10 seconds, and then rinsed with a second pure water for 10 seconds to remove the residual plating solution.
[0034] (5) Chemical palladium plating. In this embodiment, the chemical palladium plating uses a reduced palladium system. The high-temperature co-fired ceramic packaging shell treated in step (4) is placed in a chemical palladium plating solution. The palladium plating solution temperature is 60° C. The palladium plating time is 10 minutes. A chemical palladium layer is deposited on the nickel layer. After the chemical palladium plating is completed, it is first rinsed with a first pure water for 10 seconds, and then rinsed with a second pure water for 10 seconds to remove the residual plating solution.
[0035] (6) Chemical gold plating. In this embodiment, the chemical gold plating solution uses a gold replacement system, the main component of which is potassium cyanide. The high-temperature co-fired ceramic package shell treated in step (5) is placed in a chemical gold plating solution and gold-plated at 80°C for 15 minutes to replace a chemical gold layer on the palladium layer. After the chemical gold plating is completed, it is first cleaned at room temperature for 2 minutes using pure water ultrasound, and then washed with hot pure water at 70°C for 2 minutes to remove the gold plating solution. Finally, it is dried at 110°C for 5 minutes to obtain a high-temperature co-fired ceramic package shell plated with chemical nickel, palladium and gold.
[0036] The high-temperature co-fired ceramic packaging shell plated with chemical nickel, palladium and gold obtained in Example 1 has an average nickel layer thickness of 4.20 μm, an average palladium layer thickness of 0.14 μm, an average gold layer thickness of 0.16 μm, and a smooth coating surface; the high-temperature co-fired ceramic packaging shell plated with chemical nickel, palladium and gold has a coating that does not peel or bubble after high-temperature testing at 420°C and N2, and has good bonding strength between the coating and the substrate; the high-temperature co-fired ceramic packaging shell plated with chemical nickel, palladium and gold has controllable coating bonding parameters and good coating performance.
[0037] Example 2
[0038] The present embodiment provides a method for coating chemical nickel-palladium-gold on a high-temperature co-fired ceramic package shell. The high-temperature co-fired ceramic package shell is assembled into a semi-finished product by high-temperature brazing of a high-temperature co-fired ceramic substrate and metal parts.
[0039] The specific plating method comprises the following steps:
[0040] (1) Alkaline ultrasonic degreasing: In this embodiment, the alkaline degreasing agent selected is a commercially available alkaline degreasing agent, and ultrasonic cleaning is performed at 70°C for 10 minutes to remove mineral oil stains caused by mechanical processing on the surface of the high-temperature co-fired ceramic package shell; then, tap water is used for ultrasonic cleaning at room temperature for 2 minutes to clean the degreasing agent remaining on the surface of the shell; then, pure water is used for ultrasonic cleaning at room temperature for 2 minutes to remove the remaining degreasing agent.
[0041] (2) Pickling: In this embodiment, the pickling solution components are: 80 ml / L sulfuric acid, 10 g / L thiourea, and 10 ml / L emulsifier. The emulsifier is alkylphenol polyoxyethylene ether-10. The high-temperature co-fired ceramic package shell treated in step (1) is placed in the pickling solution and soaked at 65°C for 3 minutes, then ultrasonically cleaned with tap water at room temperature for 2 minutes to remove the residual pickling solution, and then cleaned with pure water at room temperature for 2 minutes.
[0042] (3) Activation with hydrochloric acid: the high temperature co-fired ceramic package shell treated in step (2) is activated with 50% by volume hydrochloric acid at 40° C. for 3 min to remove the oxide layer on the surface of the material, activate the surface of the base metal, and improve the bonding strength of the coating; after activation, it is first washed with pure water at room temperature for 20 seconds, and then washed with pure water at room temperature for 20 seconds to remove the residual hydrochloric acid solution.
[0043] (4) Chemical nickel plating. In this embodiment, the chemical nickel plating uses a medium-phosphorus chemical nickel system, and the phosphorus content of the coating is 10%. The high-temperature co-fired ceramic packaging shell treated in step (3) is placed in a nickel plating solution. The nickel plating solution temperature is 80°C, the pH is 4.74, and the nickel plating time is 40 minutes. A chemical nickel layer is obtained by plating. After the chemical nickel plating is completed, it is first rinsed with a first pure water for 10 seconds, and then rinsed with a second pure water for 10 seconds to remove the residual plating solution.
[0044] (5) Chemical palladium plating. In this embodiment, the chemical palladium plating uses a reduced palladium system. The high-temperature co-fired ceramic packaging shell treated in step (4) is placed in a palladium plating solution. The palladium plating solution temperature is 60° C. The palladium plating time is 15 minutes. A chemical palladium layer is deposited on the nickel layer. After the chemical palladium plating is completed, it is first rinsed with a first pure water rinse for 10 seconds, and then rinsed with a second pure water rinse for 10 seconds to remove the residual plating solution.
[0045] (6) Chemical gold plating. In this embodiment, the chemical gold plating solution uses a gold replacement system, the main component of which is potassium cyanide. The high-temperature co-fired ceramic package shell treated in step (5) is placed in a chemical gold plating solution and gold-plated at 80°C for 15 minutes to replace a chemical gold layer on the palladium layer. After the chemical gold plating is completed, it is first cleaned at room temperature with pure water ultrasound for 2 minutes, and then washed with hot pure water at 70°C for 2 minutes to remove the gold plating solution. Finally, it is dried at 110°C for 5 minutes to obtain a high-temperature co-fired ceramic package shell plated with chemical nickel, palladium and gold.
[0046] The high-temperature co-fired ceramic packaging shell plated with chemical nickel, palladium and gold obtained in Example 2 has an average nickel layer thickness of 5.3μm, an average palladium layer thickness of 0.21μm, an average gold layer thickness of 0.13μm, and a smooth coating surface; the high-temperature co-fired ceramic packaging shell plated with chemical nickel, palladium and gold, after high-temperature testing at 420°C and N2, the coating does not peel or bubble, and the coating has good bonding strength with the substrate.
[0047] Comparative Example 1
[0048] A method for coating chemical nickel-palladium-gold on a high-temperature co-fired ceramic package shell, the specific coating method comprising the following steps:
[0049] (1) Alkaline ultrasonic degreasing: A commercially available alkaline degreasing agent was selected and ultrasonic cleaning was performed at 70°C for 10 minutes to remove mineral oil stains caused by mechanical processing on the surface of the high-temperature co-fired ceramic package shell; then, tap water was used for ultrasonic cleaning at room temperature for 2 minutes to clean most of the degreasing agent remaining on the surface of the shell; then, pure water was used for ultrasonic cleaning at room temperature for 2 minutes to completely remove the remaining degreasing agent.
[0050] (2) Pickling: The pickling solution is selected to have the following components: 80 ml / L sulfuric acid, 10 g / L thiourea, and 10 ml / L emulsifier, wherein the emulsifier is alkylphenol polyoxyethylene ether-10. The high temperature co-fired ceramic package shell treated in step (1) is placed in the pickling solution and soaked at 65° C. for 3 min, then ultrasonically cleaned with tap water at room temperature for 2 min to remove the residual pickling solution, and then cleaned with pure water at room temperature for 2 min.
[0051] (3) Activation with hydrochloric acid: the high temperature co-fired ceramic package shell treated in step (2) is activated with 50% by volume hydrochloric acid at 40° C. for 3 min to remove the oxide layer on the surface of the material, activate the surface of the base metal, and improve the bonding strength of the coating; after activation, it is first washed with pure water at room temperature for 20 seconds, and then washed with pure water at room temperature for 20 seconds to remove the residual hydrochloric acid solution.
[0052] (4) Chemical nickel plating. In this embodiment, the chemical nickel plating uses a medium-phosphorus chemical nickel system, and the phosphorus content of the coating is 10%. The high-temperature co-fired ceramic packaging shell treated in step (3) is placed in a nickel plating solution. The nickel plating solution temperature is 80°C, the pH is 4.72, and the nickel plating time is 25 minutes. A chemical nickel layer is obtained by plating. After the chemical nickel plating is completed, it is first rinsed with a first pure water for 10 seconds, and then rinsed with a second pure water for 10 seconds to remove the residual plating solution.
[0053] (5) Chemical palladium plating. In this embodiment, the chemical palladium plating uses a reduced palladium system. The high-temperature co-fired ceramic packaging shell treated in step (4) is placed in a palladium plating solution. The palladium plating solution temperature is 60° C. The palladium plating time is 25 minutes. A chemical palladium layer is deposited on the nickel layer. After the chemical palladium plating is completed, it is first rinsed with a first pure water rinse for 10 seconds, and then rinsed with a second pure water rinse for 10 seconds to remove the residual plating solution.
[0054] (6) Chemical gold plating. In this embodiment, the chemical gold plating uses a replacement gold system. The high-temperature co-fired ceramic package shell treated in step (5) is placed in a gold plating solution and plated with gold at 80°C for 15 minutes to replace a chemical gold layer on the palladium layer. After the chemical gold plating is completed, it is first cleaned at room temperature with pure water ultrasound for 2 minutes, and then washed with hot pure water at 70°C for 2 minutes to remove the gold plating solution. Finally, it is dried at 110°C for 5 minutes to obtain a high-temperature co-fired ceramic package shell plated with chemical nickel, palladium and gold.
[0055] The high-temperature co-fired ceramic package shell plated with chemical nickel-palladium-gold obtained in Comparative Example 1 has an average nickel layer thickness of 3.85 μm, an average palladium layer thickness of 0.45 μm, and an average gold layer thickness of 0.15 μm. Compared with Example 1, the thickness of the palladium layer in Comparative Example 1 is significantly increased, which greatly affects the deposition process of the chemical gold layer, resulting in a rough surface microstructure of the gold layer, reddening of the surface of the gold layer of the prepared sample, abnormal appearance, poor bonding ability, large fluctuations in the gold wire bonding tensile test data, and bonding tensile failure.
[0056] See also Figure 1 , Figure 2 , respectively, are the actual pictures of the samples prepared in the plating process of Example 1 and Example 2. It can be seen that the sample layers are complete, the gold layer is bright and smooth, and there are no defects such as color spots. Figure 3 , which is a real picture of the sample prepared during the plating process of Comparative Example 1, it can be seen that the gold layer on the surface of the sample prepared in Comparative Example 1 begins to have spots, and the quality of the gold layer is significantly reduced. Therefore, increasing the thickness of the palladium layer too much will greatly affect the appearance of the prepared sample and form appearance defects.
[0057] The gold wire bonding test data of the samples obtained in Example 1 and Comparative Example 1 are shown in Table 1 below. It can be seen that the average value of the gold wire bonding tensile force obtained by the samples prepared in the plating process of Example 1 is significantly higher than the gold wire bonding tensile force obtained by the samples prepared in Comparative Example 1. The minimum value of the gold wire bonding tensile force of Example 1 is higher. Comparing the plating parameters, the difference between the plating parameters of Example 1 and Comparative Example 1 lies in the thickness of the palladium plating layer. When the thickness of the palladium layer increases, the gold wire bonding tensile force value decreases. However, as an isolation layer, the palladium plating layer requires a certain thickness to play an isolation role. Therefore, the palladium layer thickness obtained by the corresponding plating parameters of Example 1 is obviously more suitable for the high-temperature co-fired ceramic packaging shell, and the performance of the obtained physical sample is more excellent.
[0058] Table 1 Gold wire bonding test data of samples obtained in Example 1 and Comparative Example 1
[0059]
[0060] Note: When using a 25μm diameter gold wire, a failure is considered when the wire bonding tensile force is less than 3g.
Claims
1. A method for preparing a high temperature co-fired ceramic packaging shell by chemically plating nickel palladium gold, characterized in that: The following steps are involved: (1) Degreasing, pickling and activating the high temperature co-fired ceramic package shell; (2) chemically nickel-plating the high-temperature co-fired ceramic package shell treated in step (1), wherein the nickel layer is combined with the substrate to form a protective layer, and then the chemical nickel solution is removed by washing; (3) chemically plating palladium on the high temperature co-fired ceramic package shell treated in step (2) to form a palladium barrier layer on the chemical nickel layer, and then washing to remove the chemical palladium solution; (4) chemically gold-plating the high-temperature co-fired ceramic package shell after the treatment in step (3) to form a gold performance layer, then cleaning to remove the chemical gold solution, and drying to obtain a high-temperature co-fired ceramic package shell with a surface plated with chemical nickel-palladium-gold.
2. The method for preparing the chemical nickel-palladium-gold plating of the high temperature co-fired ceramic package shell according to claim 1, characterized in that: The chemical nickel plating in step (2) uses a medium-phosphorus chemical nickel system, the chemical nickel plating temperature is 77-83° C., the nickel ion concentration is 4.2-4.6 g / L, the pH is 4.6-4.9, and the time is 20-30 min.
3. The method for preparing the chemical nickel-palladium-gold plating of the high temperature co-fired ceramic package shell according to claim 1, characterized in that: The chemical palladium plating solution in step (3) uses a reduced palladium system, the chemical palladium plating temperature is 60-65° C., the palladium ion concentration is 1.5-2.5 g / L, the pH is 6.0-7.0, and the time is 5-10 min.
4. The method for preparing the chemical nickel-palladium-gold plating of the high temperature co-fired ceramic package shell according to claim 1, characterized in that: The chemical gold plating solution in step (4) uses a replacement gold system, the chemical gold plating temperature is 80-85° C., the gold ion concentration is 1.5-3.0 g / L, the pH is 6.0-7.0, and the time is 10-15 min.
5. The method for preparing the chemical nickel-palladium-gold plating of the high temperature co-fired ceramic package shell according to claim 1, characterized in that: The thickness of the nickel layer is 3.0-5.0 μm, and the phosphorus content is 8%-11%; the thickness of the palladium barrier layer is 0.05-0.20 μm; and the thickness of the gold performance layer is 0.05-0.20 μm.
6. The method for preparing the chemical nickel-palladium-gold plating of the high temperature co-fired ceramic package shell according to claim 1, characterized in that: The degreasing process in step (1) is as follows: placing the high temperature co-fired ceramic package shell into a degreasing agent for degreasing, and then cleaning and removing the degreasing agent; the degreasing agent is an alkaline degreasing agent, the use temperature of the alkaline degreasing agent is 65 to 75° C., and the processing time is 5 to 15 minutes.
7. The method for preparing the chemical nickel-palladium-gold plating of the high temperature co-fired ceramic package shell according to claim 1, characterized in that: The pickling process in step (1) is as follows: pickling and decontaminating the deoiled high temperature co-fired ceramic package shell, and then cleaning and removing the acid solution; the pickling temperature is 60-70° C., and the treatment time is 2-3 minutes.
8. The method for preparing the chemical nickel-palladium-gold plating of the high temperature co-fired ceramic package shell according to claim 1, characterized in that: The activation process in step (1) is: the high temperature co-fired ceramic package shell after acid washing is activated with hydrochloric acid to remove the surface oxide layer, and then the hydrochloric acid solution is washed away.
9. The method for preparing the chemical nickel-palladium-gold plating of the high temperature co-fired ceramic package shell according to claim 1, characterized in that: The pickling solution used in step (1) comprises: 75-100 ml / L of sulfuric acid, 5-10 g / L of thiourea, and 10-20 ml / L of emulsifier.
10. The method for preparing the chemical nickel-palladium-gold plating of the high temperature co-fired ceramic package shell according to claim 1, characterized in that: The activation liquid used in step (1) is hydrochloric acid with a volume fraction of 45% to 55%, the activation temperature is 35 to 45° C., and the use time is 2 to 3 minutes.