High thermal conductivity stainless steel for chip carrier and method for manufacturing the same

Abstract

The application discloses a high-thermal-conductivity stainless steel for a chip support and a preparation method thereof, and relates to the technical field of stainless steel plating. In the application, a nickel layer is first plated on the surface of a stainless steel base, then a copper layer is plated, and finally a high-thermal-conductivity coating is coated to obtain the high-thermal-conductivity stainless steel for the chip support; the nickel has high lattice matching with the stainless steel, the nickel layer has high bonding strength with the stainless steel base, the copper has a thermal conductivity much higher than that of the stainless steel, and the copper plating layer can significantly improve the thermal conductivity; the high-thermal-conductivity coating comprises a multi-epoxy-based epoxy resin, an epoxy-modified carbon nanotube, flaky silver powder, sodium stearate and a curing agent; the high-thermal-conductivity layer formed after the multi-epoxy-based epoxy resin is cured has high crosslinking density, good wear resistance and corrosion resistance, and many reaction sites, and can be quickly cured to improve the efficiency; the epoxy-modified carbon nanotube and the flaky silver powder have a synergistic effect to form a nearly comb-shaped dispersion, which is beneficial to heat dispersion and comprehensive improvement of the heat dissipation.

Description

TECHNICAL FIELD

[0001] The application relates to the technical field of stainless steel plating, and particularly relates to high-thermal-conductivity stainless steel for a chip support and a preparation method thereof. BACKGROUND

[0002] The chip support is a key bearing and connecting component of a chip and is widely applied to high-end fields such as smart phones, automobile electronics and smart wear; a copper alloy lead frame has long occupied a dominant position in the field of chip packaging, at that time, the functions of electronic equipment are relatively single, and the requirements for the size and performance of the chip are not high, and the good electrical conductivity and mechanical strength of the copper alloy can basically meet the needs of chip packaging.

[0003] With the progress of science and technology, the chip develops in the direction of high performance and high integration, for example, in the field of automobile electronics, the chip needs to work stably in a high-temperature and strong electromagnetic interference environment, and the traditional copper alloy lead frame cannot meet the needs.

[0004] Therefore, the application provides high-thermal-conductivity stainless steel for a chip support and a preparation method thereof, so that the prepared chip support has excellent thermal conductivity and corrosion resistance. SUMMARY

[0005] The application aims to provide high-thermal-conductivity stainless steel for a chip support and a preparation method thereof to solve the problems in the prior art.

[0006] To achieve the above-mentioned purpose, the application provides the following technical scheme: a preparation method of high-thermal-conductivity stainless steel for a chip support, comprising the following steps:

[0007] Step 1, taking stainless steel for cleaning, then placing it in a nickel plating solution for electroplating nickel to form a nickel plating layer, then taking it out and placing it in a copper plating solution for electroplating copper to form a copper plating layer, and obtaining composite plated stainless steel;

[0008] Step 2, taking the composite plated stainless steel, coating high-thermal-conductivity paint on the surface of the composite plated stainless steel to form a high-thermal-conductivity layer, and obtaining high-thermal-conductivity stainless steel.

[0009] Further, in step 1, the nickel plating solution comprises the following mass components: 150-250 g / L nickel sulfate, 20-30 g / L nickel oxide and 20-25 g / L boric acid.

[0010] The solvent of the nickel plating solution is deionized water.

[0011] Further, in step 1, the process conditions for electroplating nickel are as follows: temperature 50-60 DEG C, time 15-25 min, current density 1.0-2.0 A / dm 2 .

[0012] Further, in step 1, the copper plating solution comprises the following mass components: 10-20 g / L copper sulfate, 2-4 g / L sodium hypophosphite, 30-40 g / L citric acid, 0.005-0.01 g / L sodium dodecyl benzene sulfonate;

[0013] The solvent of the copper plating solution is deionized water.

[0014] Further, in step 1, the process conditions for electroplating copper are: temperature 50-60℃, time 20-30 min, current density 1.5-2.5 A / dm 2 .

[0015] Further, in step 1, the thickness of the nickel plating layer is 1-3 μm;

[0016] The thickness of the copper plating layer is 3-5 μm;

[0017] In step 2, the thickness of the high-thermal-conductivity layer is 4-6 μm.

[0018] Further, in step 1, the high-thermal-conductivity coating is prepared by the following process:

[0019] Mixing multi-oxygen-containing epoxy resin, epoxy-modified carbon nanotubes, flaky silver powder, sodium stearate, and curing agent in a mass ratio of 10:(0.5-1.0):(0.3-0.8):(0.1-0.3):(0.3-0.5), and stirring uniformly to obtain the high-thermal-conductivity coating.

[0020] Further, the multi-oxygen-containing epoxy resin is prepared by the following process:

[0021] S1: mixing 10-undecene-1-ol, 4-(trifluoromethyl)styrene, and ammonium persulfate solution, and reacting for 0.3-0.5 h, and then warming up, and then cooling to 35-40℃, and then adding sodium bicarbonate solution to adjust pH to 8-9 to obtain a hydroxyl-containing copolymer;

[0022] S2: mixing docosahexaenoic acid, m-chloroperbenzoic acid, and sodium bicarbonate solution, and reacting in an ice bath to obtain a carboxyl-containing multi-oxygen-containing compound;

[0023] S3: mixing the hydroxyl-containing copolymer, the carboxyl-containing multi-oxygen-containing compound, and concentrated sulfuric acid, and reacting in an oil bath, and then cooling to 35-40℃, and then distilling under reduced pressure to obtain the multi-oxygen-containing epoxy resin.

[0024] Further, in S1, the molar ratio of 10-undecene-1-ol to 4-(trifluoromethyl)styrene is (0.9-1.1):1;

[0025] The mass ratio of 10-undecene-1-ol to ammonium persulfate solution is 6:(0.8-1.2);

[0026] In S1, the mass fraction of the ammonium persulfate solution is 8-10%.

[0027] Further, in S1, the process condition of the heating reaction is: temperature 75-85℃, time 3-5h.

[0028] Further, in S2, the mass ratio of docosahexaenoic acid, m-chloroperbenzoic acid, and sodium bicarbonate solution is 1.5:(1.5-2.5):(1.0-1.2).

[0029] Further, in S2, the process condition of the ice bath reaction is: temperature 5-15℃, time 6-8h.

[0030] Further, the mass fraction of the sodium bicarbonate solution is 50%.

[0031] Further, in S3, the mass ratio of the hydroxyl-containing copolymer, the carboxyl-containing polyepoxide compound, and concentrated sulfuric acid is 10:(1.5-1.9):(1-2).

[0032] Further, in S3, the process condition of the oil bath heating reaction is: temperature 100-110℃, time 8-10h.

[0033] Further, in S3, the concentration of the concentrated sulfuric acid is 98%.

[0034] Further, the epoxy-modified carbon nanotube is prepared by the following process:

[0035] The polyepoxy epoxy resin, N-N dimethylacetamide, triphenylphosphine, and carboxylated carbon nanotube are mixed, stirred uniformly, heated and reacted, dried, and the epoxy-modified carbon nanotube is obtained.

[0036] Further, the ratio of the polyepoxy epoxy resin, N-N dimethylacetamide, triphenylphosphine, and carboxylated carbon nanotube is 10g:(40-50)mL:(0.05-0.1)g:(3-5)g.

[0037] Further, the process condition of the heating reaction is: temperature 70-80℃, time 20-24h.

[0038] The drying process condition is: temperature 70-80℃, time 10-12h.

[0039] Further, the curing agent is prepared by the following process:

[0040] Step A: 1,4-benzenedithiol, tetrahydrofuran, and dibutyltin dilaurate are mixed, heated to 55-65℃ in an oil bath, 2,6-diisocyanatetoluene is added, constant temperature reflux reaction is carried out, and rotary evaporation is performed to obtain a mercapto-containing compound.

[0041] Step B: the thiol-containing compound, tetrahydrofuran are mixed, and the temperature is raised to 65-75 DEG C, then the 4-diaminopyridine is added, and the reaction is continued for 3-4 hours, and then the product is obtained by rotary evaporation.

[0042] Further, in step A, the molar ratio of 1,4-benzenedithiol and 2,6-diisocyanatotoluene is 1: (2.0-2.2);

[0043] The mass ratio of 1,4-benzenedithiol, tetrahydrofuran and dibutyltin dilaurate is 10: (50-60): (0.01-0.05).

[0044] Further, in step A, the process conditions for constant temperature reflux reaction are: temperature 55-65 DEG C, time 20-24 hours.

[0045] Further, in step B, the mass ratio of the thiol-containing compound, tetrahydrofuran and 4-diaminopyridine is 1: (3-5): (0.4-0.6).

[0046] Compared with the prior art, the present application has the following advantages:

[0047] 1. In the present application, the stainless steel substrate is first subjected to nickel plating treatment, and then subjected to copper plating, the lattice matching of nickel and stainless steel is high, the nickel plating layer has high bonding force with the stainless steel substrate, and the nickel plating layer has a filling effect on the stainless steel substrate, which can improve the flatness of the stainless steel substrate surface, the nickel oxide in the nickel plating solution can maintain the stability of the nickel ion concentration in the nickel plating solution, ensure the uniform thickness of the plating layer, improve the crystallization refinement of the plating layer, and the nickel layer also has certain corrosion resistance, which can block the corrosion of the stainless steel substrate after the oxidation of the copper plating layer; the thermal conductivity of copper is much higher than that of stainless steel, and the copper plating layer can significantly improve the thermal conductivity; in addition, the lattice matching degree of copper and nickel is high, and the bonding force is good.

[0048] 2. In the present application, 10-undecene-1-ol and 4-(trifluoromethyl)styrene are first pre-reacted at room temperature under the action of ammonium persulfate to form an oligomer, and then heated to carry out free radical copolymerization, which can optimize the molecular weight distribution and retain the hydroxyl group, so as to obtain a hydroxyl-containing compound containing a benzene ring and fluorine; then, the epoxy reaction between docosahexaenoic acid and m-chloroperbenzoic acid occurs to convert the double bond into an epoxy group while retaining the carboxyl group, so as to obtain a carboxyl-containing multi-epoxy compound; finally, the hydroxyl-containing compound is esterified with the carboxyl-containing multi-epoxy compound to generate a multi-epoxy epoxy resin containing a benzene ring and fluorine; the benzene ring and fluorine have high chemical inertness and are not easy to be chemically corroded, which improves the corrosion resistance of the coating; compared with ordinary epoxy resin, the multi-epoxy epoxy resin has higher crosslinking density after curing, better wear resistance and more reaction sites, and can be quickly cured to improve the efficiency.

[0049] In the present application, one mercapto group of 1,4-benzenedithiol reacts with the isocyanate group of 2,6-diisocyanatotoluene to obtain a mercapto-containing compound, and then the mercapto-containing compound reacts with diamino pyridine to obtain a curing agent, which is a macromolecular structure, has better compatibility with a coating system than a small molecule curing agent, is not easy to precipitate, and has a long molecular chain, so that the flexibility and impact resistance of the coating can be improved after cross-linking with the epoxy resin.

[0050] 3, carbon nanotubes in epoxy resin is not good, therefore, select carboxylated carbon nanotubes, first with multi epoxy group epoxy resin, make its surface has epoxy group, then add to the coating system, can make its dispersibility increase; In addition, the coating also added flaky silver powder, flaky structure dispersed in the resin matrix can form near comb type dispersion with epoxy modified carbon nanotubes, which is beneficial to heat dispersion and comprehensive improvement of heat dissipation. DETAILED DESCRIPTION

[0051] The technical solutions in the embodiments of the present application will be described below in a clear and complete manner. Obviously, the described embodiments are only some of the embodiments of the present application, not all. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative labor fall within the scope of the present application.

[0052] In the following specific embodiments;

[0053] The stainless steel is 304 stainless steel, which is from Jiangsu Yongjin Metal Technology Co., Ltd.

[0054] Flaky silver powder, average particle size 2 μm;

[0055] Sodium bicarbonate solution, mass fraction 50%;

[0056] Concentrated sulfuric acid, concentration 98%;

[0057] Carbon nanotubes, average diameter 20 nm, average length 20 μm;

[0058] Epoxy resin, grade E44.

[0059] Embodiment 1: A preparation method of a high-thermal-conductivity stainless steel for a chip support, comprising the following steps:

[0060] (1) Preparation of high-thermal-conductivity coating:

[0061] S1: 10-Undecen-1-ol, 4-(trifluoromethyl)styrene, and ammonium persulfate solution were mixed and reacted for 0.5 h. The mixture was heated to 40 °C, and the pH was adjusted to 9 by adding sodium bicarbonate solution to obtain a hydroxyl-containing copolymer. S2: Docosahexaenoic acid, m-chloroperoxybenzoic acid, and sodium bicarbonate solution were mixed and reacted in an ice bath to obtain a carboxyl-containing polyepoxide compound. S3: The hydroxyl-containing copolymer, the carboxyl-containing polyepoxide compound, and concentrated sulfuric acid were mixed and reacted in an oil bath. The mixture was cooled to 40 °C and distilled under reduced pressure to obtain a polyepoxide-containing epoxy resin. In S1, the molar ratio of 10-undecen-1-ol to 4-(trifluoromethyl)styrene was 1. The mass ratio of 10-undecen-1-ol to ammonium persulfate solution is 6:1.2; in S1, the mass fraction of ammonium persulfate solution is 10%; in S1, the process conditions for the heated reaction are: temperature 85℃, time 5h; in S2, the mass ratio of docosahexaenoic acid, m-chloroperoxybenzoic acid, and sodium bicarbonate solution is 1.5:2.5:1.2; in S2, the process conditions for the ice bath reaction are: temperature 15℃, time 8h; in S3, the mass ratio of hydroxyl-containing copolymer, carboxyl-containing polyepoxide compound, and concentrated sulfuric acid is 10:1.9:2; in S3, the process conditions for the oil bath heating reaction are: temperature 110℃, time 10h.

[0062] Polyepoxy resin, N,N dimethylacetamide, triphenylphosphine, and carboxylated carbon nanotubes were mixed in a ratio of 10g:50mL:0.1g:5g, stirred evenly, heated to react, and dried to obtain epoxy-modified carbon nanotubes. The heating reaction conditions were: temperature 80℃, time 24h; the drying process conditions were: temperature 80℃, time 12h.

[0063] Step A: Mix 1,4-phenyldithiol, tetrahydrofuran, and dibutyltin dilaurate, heat in an oil bath to 65°C, add toluene 2,6-diisocyanate, reflux at a constant temperature, and rotary evaporate to obtain a mercapto-containing compound; Step B: Mix the mercapto-containing compound and tetrahydrofuran, heat to 75°C, add diaminopyridine, continue the reaction for 4 hours, and rotary evaporate to obtain a curing agent; In Step A, the molar ratio of 1,4-phenyldithiol and toluene 2,6-diisocyanate is 1:2.2; the mass ratio of 1,4-phenyldithiol, tetrahydrofuran, and dibutyltin dilaurate is 10:60:0.05; In Step A, the process conditions for the isothermal reflux reaction are: temperature 65°C, time 24 hours; In Step B, the mass ratio of the mercapto-containing compound, tetrahydrofuran, and diaminopyridine is 1:5:0.6;

[0064] Polyepoxy resin, epoxy-modified carbon nanotubes, flake silver powder, sodium stearate, and curing agent are mixed in a mass ratio of 10:1.0:0.8:0.3:0.5 and stirred evenly to obtain a high thermal conductivity coating.

[0065] (2) Preparation of high thermal conductivity stainless steel:

[0066] Step 1, take stainless steel for cleaning, and then place in nickel plating solution, electroplating nickel, forming 3 μm of nickel plating layer, then take out and place in copper plating solution, electroplating copper, forming 5 μm of copper plating layer, to get composite plated stainless steel; Step 2, take composite plated stainless steel, coating high thermal conductivity paint on its surface, forming 6 μm of high thermal conductivity layer, to get high thermal conductivity stainless steel; in Step 1, the nickel plating solution comprises the following mass components: 250 g / L nickel sulfate, 30 g / L nickel oxide, 25 g / L boric acid; the solvent of the nickel plating solution is deionized water; in Step 1, the copper plating solution comprises the following mass components: 20 g / L copper sulfate, 4 g / L sodium hypophosphite, 40 g / L citric acid, 0.01 g / L sodium dodecyl benzene sulfonate; the solvent of the copper plating solution is deionized water; in Step 1, the process conditions of electroplating nickel are: temperature 60℃, time 25 min, current density 2.0 A / dm 2 ; in Step 1, the process conditions of electroplating copper are: temperature 60℃, time 30 min, current density 2.5 A / dm 2 .

[0067] Embodiment 2: a preparation method of high thermal conductivity stainless steel for chip holder, comprising the following steps:

[0068] (1) preparation of high thermal conductivity paint:

[0069] S1: mix 10-undecene-1-ol, 4-(trifluoromethyl)styrene, ammonium persulfate solution, react for 0.4 h, warm up reaction, cool down to 38℃, add sodium bicarbonate solution to adjust pH to 8, to get hydroxyl-containing copolymer; S2: mix docosahexaenoic acid, m-chloroperbenzoic acid, sodium bicarbonate solution, ice bath reaction, to get carboxyl-containing polycyclic epoxy compound; S3: mix hydroxyl-containing copolymer, carboxyl-containing polycyclic epoxy compound, concentrated sulfuric acid, oil bath heating reaction, cool down to 38℃, reduce pressure distillation, to get polycyclic epoxy epoxy resin; in S1, the molar ratio of 10-undecene-1-ol and 4-(trifluoromethyl)styrene is 1.0:1; the mass ratio of 10-undecene-1-ol and ammonium persulfate solution is 6:1.0; in S1, the mass fraction of ammonium persulfate solution is 9%; in S1, the process conditions of warm up reaction are: temperature 80℃, time 4 h; in S2, the mass ratio of docosahexaenoic acid, m-chloroperbenzoic acid and sodium bicarbonate solution is 1.5:2.0:1.1; in S2, the process conditions of ice bath reaction are: temperature 10℃, time 7 h; in S3, the mass ratio of hydroxyl-containing copolymer, carboxyl-containing polycyclic epoxy compound and concentrated sulfuric acid is 10:1.7:1.5; in S3, the process conditions of oil bath heating reaction are: temperature 105℃, time 9 h;

[0070] Mixing multi-epoxy epoxy resin, N-N dimethylacetamide, triphenylphosphine, carboxylated carbon nanotubes in proportion 10g:45mL:0.08g:4g, stirring uniformly, heating reaction, drying, obtaining epoxy modified carbon nanotubes; the process conditions of heating reaction are: temperature 75℃, time 22h; the process conditions of drying are: temperature 75℃, time 11h;

[0071] Step A: mixing 1,4-benzenedithiol, tetrahydrofuran, dibutyltin dilaurate, heating to 60℃ in oil bath, adding 2,6-diisocyanate toluene, constant temperature refluxing reaction, rotary evaporation, obtaining thiol-containing compound; Step B: mixing thiol-containing compound, tetrahydrofuran, heating to 70℃, adding diamino pyridine, continuing to react for 3.5h, rotary evaporation, obtaining curing agent; in Step A, the molar ratio of 1,4-benzenedithiol, 2,6-diisocyanate toluene is 1:2.1; the mass ratio of 1,4-benzenedithiol, tetrahydrofuran, dibutyltin dilaurate is 10:55:0.03; in Step A, the process conditions of constant temperature refluxing reaction are: temperature 60℃, time 22h; in Step B, the mass ratio of thiol-containing compound, tetrahydrofuran, diamino pyridine is 1:4:0.5;

[0072] Mixing multi-epoxy epoxy resin, epoxy modified carbon nanotubes, flaky silver powder, sodium stearate, curing agent in mass ratio 10:0.8:0.5:0.2:0.4, stirring uniformly, obtaining high thermal conductivity coating;

[0073] (2) Preparation of high thermal conductivity stainless steel:

[0074] Step 1, taking stainless steel for cleaning, then placing in nickel plating solution, electroplating nickel to form 2μm nickel plating layer, then taking out and placing in copper plating solution, electroplating copper to form 4μm copper plating layer, obtaining composite plated stainless steel; Step 2, taking composite plated stainless steel, coating high thermal conductivity coating on the surface to form 5μm high thermal conductivity layer, obtaining high thermal conductivity stainless steel; in Step 1, the nickel plating solution comprises the following mass components: 200g / L nickel sulfate, 25g / L nickel oxide, 23g / L boric acid; the solvent of the nickel plating solution is deionized water; in Step 1, the copper plating solution comprises the following mass components: 15g / L copper sulfate, 3g / L sodium hypophosphite, 35g / L citric acid, 0.008g / L sodium dodecyl benzene sulfonate; the solvent of the copper plating solution is deionized water; in Step 1, the process conditions of electroplating nickel are: temperature 55℃, time 20min, current density 1.5A / dm 2 ; in Step 1, the process conditions of electroplating copper are: temperature 55℃, time 25min, current density 2.0A / dm 2 .

[0075] Example 3: a method for preparing high thermal conductivity stainless steel for chip support, comprising the following steps:

[0076] (1) Preparation of high thermal conductive paint:

[0077] S1: 10-undecene-1-ol, 4-(trifluoromethyl)styrene, ammonium persulfate solution was mixed, and the reaction was carried out for 0.3 h, the temperature was raised, and the temperature was lowered to 35℃, sodium bicarbonate solution was added to adjust the pH to 8, and a hydroxyl-containing copolymer was obtained; S2: docosahexaenoic acid, m-chloroperbenzoic acid, sodium bicarbonate solution was mixed, and the reaction was carried out in ice bath, and a carboxyl-containing polyepoxide compound was obtained; S3: the hydroxyl-containing copolymer, the carboxyl-containing polyepoxide compound, and concentrated sulfuric acid were mixed, and the reaction was carried out in oil bath heating, and the temperature was lowered to 35℃, and the reaction was carried out under reduced pressure distillation, and a polyepoxy epoxy resin was obtained; in S1, the molar ratio of 10-undecene-1-ol and 4-(trifluoromethyl)styrene was 0.9:1; the mass ratio of 10-undecene-1-ol and ammonium persulfate solution was 6:0.8; in S1, the mass fraction of ammonium persulfate solution was 8%; in S1, the process conditions for temperature raising reaction were: temperature 75℃, time 3h; in S2, the mass ratio of docosahexaenoic acid, m-chloroperbenzoic acid and sodium bicarbonate solution was 1.5:1.5:1.0; in S2, the process conditions for ice bath reaction were: temperature 5℃, time 6h; in S3, the mass ratio of hydroxyl-containing copolymer, carboxyl-containing polyepoxide compound and concentrated sulfuric acid was 10:1.5:1; in S3, the process conditions for oil bath heating reaction were: temperature 100℃, time 8h;

[0078] The polyepoxy epoxy resin, N-N dimethylacetamide, triphenylphosphine, and carboxylated carbon nanotubes were mixed in proportions of 10g:40mL:0.05g:3g, stirred uniformly, heated and reacted, and dried to obtain epoxy modified carbon nanotubes; the process conditions for heating reaction were: temperature 70℃, time 20h; the process conditions for drying were: temperature 70℃, time 10h;

[0079] Step A: 1,4-benzenedithiol, tetrahydrofuran, dibutyltin dilaurate were mixed, and the temperature was raised to 55℃ in oil bath, 2,6-diisocyanate toluene was added, and the reaction was carried out under constant temperature reflux, and rotary evaporation was carried out to obtain a thiol-containing compound; Step B: the thiol-containing compound, tetrahydrofuran were mixed, and the temperature was raised to 65℃, and diamino pyridine was added, and the reaction was continued for 3h, and rotary evaporation was carried out to obtain a curing agent; in Step A, the molar ratio of 1,4-benzenedithiol and 2,6-diisocyanate toluene was 1:2.0; the mass ratio of 1,4-benzenedithiol, tetrahydrofuran, and dibutyltin dilaurate was 10:50:0.01; in Step A, the process conditions for constant temperature reflux reaction were: temperature 55℃, time 20h; in Step B, the mass ratio of thiol-containing compound, tetrahydrofuran, and diamino pyridine was 1:3:0.4;

[0080] Polyepoxy resin, epoxy-modified carbon nanotubes, flake silver powder, sodium stearate, and curing agent are mixed in a mass ratio of 10:0.5:0.3:0.1:0.3 and stirred evenly to obtain a high thermal conductivity coating.

[0081] (2) Preparation of high thermal conductivity stainless steel:

[0082] Step 1: Clean the stainless steel, then place it in a nickel plating solution for nickel plating to form a 1μm nickel layer. Next, remove it and place it in a copper plating solution for copper plating to form a 3μm copper layer, resulting in a composite-plated stainless steel. Step 2: Coat the surface of the composite-plated stainless steel with a high thermal conductivity coating to form a 4μm high thermal conductivity layer, resulting in high thermal conductivity stainless steel. In Step 1, the nickel plating solution includes the following components by mass: 150g / L nickel sulfate, 20g / L nickel oxide, and 20g / L boric acid; the solvent for the nickel plating solution is deionized water. In Step 1, the copper plating solution includes the following components by mass: 10g / L copper sulfate, 2g / L sodium hypophosphite, 30g / L citric acid, and 0.005g / L sodium dodecylbenzenesulfonate; the solvent for the copper plating solution is deionized water. In Step 1, the electroplating conditions for nickel are: temperature 50℃, time 15min, and current density 1.0A / dm³. 2 In step 1, the electroplating copper process conditions are: temperature 50℃, time 20 min, and current density 1.5 A / dm³. 2 .

[0083] Comparative Example 1: Compared with Example 1, the polyepoxy epoxy resin was replaced with a commercially available epoxy resin, while all other conditions remained unchanged.

[0084] Comparative Example 2: Compared with Example 1, the curing agent was replaced with ethylenediamine, while the other conditions remained the same.

[0085] Comparative Example 3: Compared with Example 1, no modification was made to the carbon nanotubes, and all other conditions remained unchanged.

[0086] Comparative Example 4: Compared with Example 1, the polyepoxy epoxy resin was replaced with commercially available epoxy resin, the curing agent was replaced with ethylenediamine, and the carbon nanotubes were not modified, while the other conditions remained unchanged.

[0087] Experiment: The high thermal conductivity stainless steel obtained in the examples and comparative examples was used to test its performance;

[0088] Thermal conductivity: The thermal conductivity of high thermal conductivity stainless steel was tested using a YBF-2 thermal conductivity tester.

[0089] Corrosion resistance: According to ASTM-B117-2011, a 5% NaCl solution was used for testing at 35°C for 720 hours.

[0090] The table below shows the performance test results of high thermal conductivity stainless steel;

[0091]

[0092] According to the data in the above table, the following conclusions can be drawn:

[0093] Compared with Example 1, Comparative Example 1 replaces the multi-epoxy epoxy resin with a commercially available epoxy resin, and the thermal conductivity of the stainless steel decreases and the corrosion rate increases to a greater extent. The reason is that the multi-epoxy epoxy resin has a higher crosslinking density after curing than the ordinary epoxy resin, and the multi-epoxy epoxy resin contains benzene rings and fluorine, both of which have high chemical inertness and are not prone to chemical corrosion;

[0094] Compared with Example 1, Comparative Example 2 replaces the curing agent with ethylenediamine, and the thermal conductivity of the stainless steel decreases and the corrosion rate increases. The reason is that the curing agent in the example has a macromolecular structure, which has better compatibility with the coating system than the small molecule curing agent, and is not prone to precipitation;

[0095] Compared with Example 1, Comparative Example 3 does not modify the carbon nanotubes, and the thermal conductivity of the stainless steel decreases and the corrosion rate increases. The reason is that the carbon nanotubes have poor dispersibility in the coating and are prone to agglomeration, which may cause the conduction path to be discontinuous, resulting in a decrease in thermal conductivity;

[0096] Compared with Example 1, Comparative Example 4 replaces the multi-epoxy epoxy resin with a commercially available epoxy resin, replaces the curing agent with ethylenediamine, and does not modify the carbon nanotubes. The thermal conductivity of the stainless steel is the worst and the corrosion rate is the highest;

[0097] In summary, the settings of the components and process conditions of the high thermal conductivity coating in the present application can improve the thermal conductivity of the prepared high thermal conductivity stainless steel while maintaining good corrosion resistance.

[0098] It will be obvious to a person skilled in the art that the application is not limited to the details of the above-described exemplary embodiments, but can be implemented in other concrete forms without departing from the spirit or essential characteristics of the application. Therefore, the embodiments should be considered exemplary and non-limiting, and the scope of the application is defined by the appended claims rather than the above description, and it is intended to encompass all variations falling within the meaning and scope of the equivalent elements of the claims.

Claims

1. A method for producing a high thermal conductivity stainless steel for a chip carrier, characterized by: The method comprises the following steps: ​ Step 1, take stainless steel for cleaning, and then place it in a nickel plating solution for electroplating nickel to form a nickel plating layer, and then take it out and place it in a copper plating solution for electroplating copper to form a copper plating layer, thereby obtaining a composite plated stainless steel; Step 2, take the composite plated stainless steel, coat high-thermal-conductivity paint on the surface of the composite plated stainless steel to form a high-thermal-conductivity layer, and obtain high-thermal-conductivity stainless steel; In step 1, the high-thermal-conductivity paint is prepared by the following process: Mix multi-oxygen-containing epoxy resin, epoxy-modified carbon nanotubes, flaky silver powder, sodium stearate and curing agent according to a mass ratio of 10: (0.5-1.0): (0.3-0.8): (0.1-0.3): (0.3-0.5), and stir until uniform to obtain the high-thermal-conductivity paint.

2. The method of claim 1, wherein the high thermal conductivity stainless steel for a chip carrier is prepared by the steps of: The multi-oxygen-containing epoxy resin is prepared by the following process: ​ S1: mix 10-undecene-1-ol, 4-(trifluoromethyl)styrene and ammonium persulfate solution, and react for 0.3-0.5 h under temperature rising, and then cool to 35-40 DEG C, add sodium bicarbonate solution to adjust pH to 8-9 to obtain a hydroxyl-containing copolymer; S2: mix docosahexaenoic acid, m-chloroperbenzoic acid and sodium bicarbonate solution, and react under ice bath to obtain a carboxyl-containing multi-oxygen-containing compound; S3: mix the hydroxyl-containing copolymer, the carboxyl-containing multi-oxygen-containing compound and concentrated sulfuric acid, and react under oil bath heating, and then cool to 35-40 DEG C and distill under reduced pressure to obtain the multi-oxygen-containing epoxy resin.

3. The method for preparing a high thermal conductivity stainless steel for a chip scaffold according to claim 1, characterized in that: The curing agent is prepared by the following process: Step A: mix 1,4-benzenedithiol, tetrahydrofuran and dibutyltin dilaurate, heat to 55-65 DEG C under oil bath, add 2,6-diisocyanatetoluene, and reflux react under constant temperature, and then rotary evaporate to obtain a mercapto-containing compound; Step B: mix the mercapto-containing compound and tetrahydrofuran, heat to 65-75 DEG C, add diamino pyridine, and continue to react for 3-4 h, and then rotary evaporate to obtain the curing agent.

4. The method of claim 1, wherein the high thermal conductivity stainless steel for a chip carrier is prepared by the steps of: The epoxy-modified carbon nanotube is prepared by the following process: ​ Mix multi-oxygen-containing epoxy resin, N-N dimethylacetamide, triphenylphosphine and carboxylated carbon nanotube, stir until uniform, heat to react, and then dry to obtain the epoxy-modified carbon nanotube.

5. The method of claim 2, wherein the high thermal conductivity stainless steel for a chip carrier is prepared by the steps of: In S1, the molar ratio of 10-undecene-1-ol to 4-(trifluoromethyl)styrene is (0.9-1.1):1; ​ The mass ratio of 10-undecene-1-ol to ammonium persulfate solution is 6:(0.8-1.2). In S1, the mass fraction of the ammonium persulfate solution is 8-10%.

6. The method of claim 2, wherein the high thermal conductivity stainless steel for a chip carrier is prepared by the steps of: In S2, the mass ratio of docosahexaenoic acid to m-chloroperbenzoic acid to sodium bicarbonate solution is 1.5:(1.5-2.5):(1.0-1.2). ​ 7. The method of claim 3, wherein the high thermal conductivity stainless steel for a chip carrier is prepared by the steps of: In step A, the molar ratio of 1,4-benzenedithiol to 2,6-diisocyanatetoluene is 1:(2.0-2.2); ​ The mass ratio of 1,4-benzenedithiol to tetrahydrofuran to dibutyltin dilaurate is 10:(50-60):(0.01-0.05).

8. The method of claim 3, wherein the high thermal conductivity stainless steel for a chip carrier is prepared by the steps of: In step B, the mass ratio of the mercapto-containing compound to tetrahydrofuran to diamino pyridine is 1:(3-5):(0.4-0.6). ​ 9. The method of claim 4, wherein the high thermal conductivity stainless steel for a chip carrier is prepared by the steps of: The ratio of polycarboxylated carbon nanotubes, N-N dimethylacetamide, triphenylphosphine, carboxylated carbon nanotubes is 10g: (40~50)mL: (0.05~0.1)g: (3~5)g. ​ 10. A high thermal conductivity stainless steel for a chip carrier, characterized by: The preparation method according to any one of claims 1~9.

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