A method for manufacturing a selectively gold-plated double-sided heat dissipation copper-based substrate

Abstract

The present invention relates to the field of double-sided heat dissipation copper-based carriers, and specifically discloses a method for manufacturing a double-sided heat dissipation copper-based carrier with selective gold plating. The method comprises the following steps: preparing AlN ceramics and copper sheets; pre-oxidizing the copper sheets: pre-oxidizing the copper sheets to obtain pre-oxidized copper sheets; placing a number of pre-oxidized copper sheets obtained in S1 horizontally on a mesh belt, with the oxidized surface facing upward, and vertically placing the AlN ceramics to be evaporated on the surface thereof for evaporation; obtaining copper-containing AlN ceramics; oxidizing the copper-containing AlN ceramics obtained in S3 to obtain copper porcelain; sintering the copper porcelain obtained in S4 once to obtain copper porcelain A; performing pattern transfer, product cutting and slicing, and porcelain sheet cutting and slicing on the copper porcelain A obtained in S5 in sequence to obtain porcelain sheets; performing secondary sintering on the porcelain sheets obtained in S6 to obtain a copper-based carrier; performing selective gold plating on the copper-based carrier obtained in S7 to obtain a selective gold-plated double-sided heat dissipation copper-based carrier.

Description

Technical Field

[0001] The invention relates to the technical field of double-sided heat dissipation copper-based carrier boards, in particular to a method for manufacturing a selectively gold-plated double-sided heat dissipation copper-based carrier board. Background Art

[0002] Nowadays, in the field of ceramic metallization, various copper-clad ceramic products, such as DBC, AMB, DPC, TPC, etc., are quite common. Although there are differences in the production process of the above products, they are generally single-sided or double-sided metallization on the ceramic surface, that is, copper is coated on the ceramic. In view of the special needs of the in-vehicle wireless charging industry, it is necessary to apply high thermal conductivity ceramic sheets on the upper and lower surfaces of copper respectively to achieve the purpose of rapid heat dissipation. However, there are significant differences between the warping mode and double-sided copper-clad products, so the existing sintering method is no longer applicable; however, the copper sheet is sandwiched between two ceramic sheets, which will greatly affect the etching process, that is, once the copper sheet is sintered, it will not be accurately etched; in addition, this type of product often has no special positioning marks, and a new positioning method is required to lock the position of the subsequent selective coating. Considering the above difficulties, this type of product is extremely difficult, and no manufacturer has been able to produce it on a large scale so far. A new process is urgently needed to solve the current problems in the industry.

[0003] In summary, it is of great significance to prepare a selectively gold-plated double-sided heat dissipation copper substrate carrier. Summary of the invention

[0004] The object of the present invention is to provide a method for manufacturing a selectively gold-plated double-sided heat dissipating copper-based carrier board to solve the problems raised in the above-mentioned background technology.

[0005] A method for manufacturing a selectively gold-plated double-sided heat dissipation copper-based substrate, comprising the following steps:

[0006] S1: Raw material preparation: Prepare AlN ceramic and copper sheet;

[0007] S2: Pre-oxidation of copper sheet: pre-oxidizing the copper sheet to obtain a pre-oxidized copper sheet;

[0008] S3: AlN ceramic evaporation: several pre-oxidized copper sheets obtained in S1 are placed horizontally on the mesh belt with the oxidized surface facing upward, and the AlN ceramic to be evaporated is placed vertically on the surface thereof for evaporation to obtain copper-containing AlN ceramic;

[0009] S4: oxidation of copper-containing AlN ceramics: oxidizing the copper-containing AlN ceramics obtained in S3 to obtain copper ceramics;

[0010] S5: primary sintering of copper porcelain: sintering the copper porcelain obtained in S4 once to obtain copper porcelain A;

[0011] S6: Pattern transfer and slicing: the copper porcelain A obtained in S5 is subjected to pattern transfer, product cutting and slicing, and porcelain slice cutting and slicing in sequence to obtain porcelain slices;

[0012] S7: performing secondary sintering on the ceramic sheet obtained in S6 to obtain a copper-based carrier plate;

[0013] S8: The copper-based carrier obtained in S7 is subjected to selective gold plating to obtain a selective gold-plated double-sided heat dissipating copper-based carrier.

[0014] More optimally, in S1, the process parameters of the pre-oxidation treatment are: annealing treatment at an oxygen content of 600-800PPM, and the annealing temperature zones include 1-11 temperature zones, namely: temperature zone 1 is 500-520°C, temperature zone 2 is 680-700°C, temperature zone 3 is 780-800°C, temperature zone 4 is 790-810°C, temperature zone 5 is 760-800°C, temperature zone 6 is 760-800°C, temperature zone 7 is 760-800°C, temperature zone 8 is 760-800°C, temperature zone 9 is 700-740°C, temperature zone 10 is 640-680°C, and temperature zone 11 is 620-660°C.

[0015] More optimally, in S3, the pre-oxidized copper sheet is pre-bent in both directions using a pre-bending machine before placement; when the AlN ceramic is vertically placed on the surface of the pre-oxidized copper sheet, the pre-oxidized copper sheet overlaps front and back by 4.5 to 5.5 mm.

[0016] More optimally, in S3, the process parameters of evaporation are: setting the 100mL flowmeter to 5% oxygen flow and the belt speed to 8inch / min; the evaporation includes 1 to 8 temperature zones, namely: temperature zone 1 is 720-740℃, temperature zone 2 is 820-840℃, temperature zone 3 is 905-925℃, temperature zone 4 is 940-960℃, temperature zone 5 is 930-970℃, temperature zone 6 is 930-970℃, temperature zone 7 is 930-970℃, and temperature zone 8 is 880-920℃.

[0017] More optimally, in S2, the oxidation temperature of the copper-containing AlN ceramic is 1000-1100° C., and the oxidation time is 4-6 hours.

[0018] More optimally, in S1, the specification of AlN ceramic is 138×190mm 2 , the specification of copper sheet is 132×184mm 2 .

[0019] More optimally, in S5, the process parameters of the primary sintering are: the primary sintering includes 1 to 10 temperature zones, namely: temperature zone 1 is 770-790°C, temperature zone 2 is 900-910°C, temperature zone 3 is 1020-1030°C, temperature zone 4 is 1090-1100°C, temperature zone 5 is 1090-1100°C, temperature zone 6 is 1090-1100°C, temperature zone 7 is 1086-1094°C, temperature zone 8 is 1086-1094°C, temperature zone 9 is 1030-1040°C, and temperature zone 10 is 995-1005°C.

[0020] More optimally, in S7, the process parameters of the secondary sintering are: the secondary sintering includes 1 to 10 temperature zones, namely: temperature zone 1 is 775-785°C, temperature zone 2 is 900-910°C, temperature zone 3 is 1020-1030°C, temperature zone 4 is 1092-1100°C, temperature zone 5 is 1092-1100°C, temperature zone 6 is 1090-1097°C, temperature zone 7 is 1088-1094°C, temperature zone 9 is 1030-1040°C, and temperature zone 10 is 995-1005°C.

[0021] More optimally, in S6, the pattern transfer includes film sticking, exposure, development, etching, and film stripping.

[0022] The most optimized etching process parameters are: etching temperature is 50±3°C, upper and lower spray pressures are 2.7±0.3kg / cm 2 and 2.2±0.4kg / cm 2 ; The solution used for the etching is 1.9±0.2N hydrochloric acid.

[0023] In the optimized S8, the process parameters of the selective gold plating are: pH value of 4.4-4.8, temperature of 83-87°C, time of 120-640 seconds, pressure of 0.2-0.6 kg / cm 2 ; The gold plating solution is used in the selective gold plating process, and the gold plating solution contains the following components: 160-240 ml / L of agent, gold concentration of 0.8-1.2 g / L, nickel ion concentration of ≤900 mg / L, copper ion concentration of ≤5 mg / L, and iron ion concentration of ≤1 mg / L.

[0024] More optimally, the raw materials of the agent A include the following components: 19.5-20 wt% of carboxylate, 4-4.2 wt% of aminocarboxylate, and 74-78 wt% of water.

[0025] Compared with the prior art, the present invention is relatively optimized and has the following beneficial effects: (1) It introduces the method of vapor deposition and oxidation of AlN ceramics; (2) The present invention uses a special sintering method of first sintering the first side of the ceramic in a master state and then sintering the second side of the ceramic in a small piece state; (3) Without changing the original structure of the exposure machine, the present invention adopts a specific film and sets two positioning lines on the upper and lower sides of the film. The upper and lower sides of the product are precisely positioned by overlapping with the two positioning lines, thereby realizing the selective gold plating of specific areas of small-sized products. BRIEF DESCRIPTION OF THE DRAWINGS

[0026] The accompanying drawings are used to provide a further understanding of the present invention and constitute a part of the specification. Together with the embodiments of the present invention, they are used to explain the present invention and do not constitute a limitation of the present invention. In the accompanying drawings:

[0027] Figure 1 It is a pre-oxidized copper sheet for positive and negative pre-bending;

[0028] Figure 2 It is a pre-oxidized copper sheet with the oxidized side facing up and placed horizontally on the screen with a diagram;

[0029] Figure 3 This is a partial enlarged view of the overlap of the pre-oxidized copper sheet before and after;

[0030] Figure 4 is a picture of AlN ceramic to be oxidized;

[0031] Figure 5 This is the copper porcelain A figure obtained after the copper porcelain is sintered once;

[0032] Figure 6 It is the CAD specified drawing of copper porcelain A;

[0033] Figure 7 It is a single-sided semi-finished product after the pattern transfer of copper porcelain A;

[0034] Figure 8 It is a master cutting program diagram of a single-sided semi-finished product;

[0035] Fig. 9 It is a small piece of copper porcelain cut from a single-sided semi-finished product;

[0036] Fig.10 It is a diagram of the tile cutting procedure;

[0037] Fig.11 It is the cut porcelain piece;

[0038] Fig.12 It is the tile after slicing;

[0039] Fig.13 It is to fix the porcelain piece with a small piece of copper porcelain;

[0040] Fig.14 It is a fixed bracket diagram;

[0041] Fig.15 It is a copper-based carrier board diagram;

[0042] Fig.16 It is a selective gold-plated double-sided heat dissipation copper base substrate. DETAILED DESCRIPTION

[0043] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0044] A method for manufacturing a selectively gold-plated double-sided heat dissipation copper-based substrate, comprising the following steps:

[0045] S1: Prepare 138×190mm 2 AlN ceramic and 132×184mm 2 Copper sheets as raw materials;

[0046] S2: Pre-oxidation of copper sheet: pre-oxidizing the copper sheet to obtain a pre-oxidized copper sheet;

[0047] Among them, the treatment process of pre-oxidation treatment is: belt speed 170mm / min, total time about 1h; oxidation parameters: oxygen content 600-800PPM; annealing temperature 1-4 zone (±10℃), 5-11 zone (±20℃), as shown in Table 1;

[0048] Temperature Zone 1 2 3 4 5 6 7 8 9 10 11 temperature 510℃ 690℃ 790℃ 800℃ 780℃ 780℃ 780℃ 780℃ 720℃ 660℃ 640℃

[0049] Table 1

[0050] S3: AlN ceramic evaporation: several pre-oxidized copper sheets obtained in S1 are placed horizontally on the mesh belt, such as Figure 1 As shown, the oxidized surface faces upward, and the AlN ceramic to be evaporated is placed vertically on the surface to evaporate; and the copper-containing AlN ceramic is obtained;

[0051] Among them, the evaporation treatment process is shown in Table 2:

[0052]

[0053] Table 2

[0054] S4: insert the copper-containing AlN ceramic in S3 into the quartz boat in the muffle furnace and maintain it at 1000℃ for 1 hour and 50 minutes, then raise the temperature to 1100℃ and maintain it for half an hour; cool down for about 3 hours, when the display temperature drops below 100℃, open the side door and use clean bamboo tweezers to pick out the copper ceramics piece by piece and put them into a clean turnover box;

[0055] S5: copper porcelain primary sintering: the oxidized AlN porcelain sheet obtained in S4 is placed on a mesh belt, with the oxidized surface facing upward, and then the oxidized surface of the copper sheet is placed downward, and sintered once to obtain copper porcelain A; Figure 5 As shown;

[0056] Among them, the process parameters of the primary sintering are the sintering temperatures of zone 1 (±10°C), zone 2-6 (±5°C), zone 7-8 (±4°C), zone 9-10 (±5°C), as shown in Table 3:

[0057]

[0058] Table 3

[0059] S6 Pattern transfer and slicing: The copper porcelain A obtained in S5 is subjected to pattern transfer in sequence (such as Figure 7 ), product cutting and slicing (such as Fig. 9 ), tile cutting and slicing (such as Figures 10-12 ), and obtain a tile;

[0060] Among them, image transfer includes film pasting, exposure, development, etching, film stripping and other processes;

[0061] Among them, the film pasting section parameters are shown in Table 4:

[0062] project Control conditions Inlet pressure 0.55Mpa Front upper pressure roller temperature Dry method: 125℃ Front lower roller temperature Dry method: 125℃ Rear upper pressure wheel temperature 120℃ Rear lower roller temperature 120℃ Film laminating machine speed 3.0m / min Film pressure <![CDATA[4.0kg / cm 2 ]]>

[0063] Table 4

[0064] Among them, the exposure section parameters are shown in Table 5:

[0065] project Control conditions Vacuum degree of upper film ≤-650mmHg Lower film vacuum ≤-650mmHg Upper frame chamber vacuum ≤-320mmHg Vacuum degree of lower frame chamber ≤-320mmHg Table temperature 22℃ Exposure scale energy grid 7 grid

[0066] Table 5

[0067] In the developing section, the developing tank temperature is 30°C, the developer concentration is 1%, the developing speed is 1.5m / min, and the upper and lower spray pressures are 1.6kg / cm 2 and 1.5kg / cm 2 .

[0068] In the etching section, the etching tank temperature is 50°C, the specific gravity is 1.295, the hydrochloric acid concentration is 1.9N, and the upper and lower spray pressures are 2.7kg / cm 2 and 2.2kg / cm 2,The line speed varies slightly depending on the product, as shown in Table 6 below:

[0069] Copper thickness(mm) Conveying speed (m / min) 0.8 0.5 0.5 0.7 0.4 0.8 0.3 1.3 0.25 1.5 0.2 1.8

[0070] Table 6

[0071] In the film removal stage, the film removal concentration is 4%, the film removal temperature is 50℃, the film removal speed is ≤1.4m / min, and the upper and lower spray pressures are 2.5kg / cm 2 and 2.2kg / cm 2

[0072] S7: The ceramic sheet obtained in S6 and the slices cut from the product are subjected to secondary sintering, and the secondary sintering is performed under the premise of using a special fixing fixture to obtain a copper-based carrier board, such as Fig.15 As shown;

[0073] Among them, the process parameters of the secondary sintering, sintering temperature 1-3 zone (±5°C), 4-6 zone (±4°C), 7-8 zone (±3°C), 9-10 zone (±5°C), as shown in Table 7:

[0074]

[0075] Table 7

[0076] S8: The copper-based carrier obtained in S7 is aligned with the upper and lower sides by using a specific film, and then subjected to development, chemical plating, and film removal to achieve selective gold plating in the designated area to obtain a selective gold-plated double-sided heat dissipation copper-based carrier, such as Fig.16 shown.

[0077] Among them, the process parameters of selective gold plating are shown in Table 8:

[0078]

[0079] Table 8

[0080] Among them, the main ingredients of Agent A are shown in Table 9:

[0081] Components Concentration or concentration range (mass fraction, %) Carboxylates 19.9％ Amino acid salt 4.1％ water 76％

[0082] Table 9

[0083] It should be noted that, in this article, relational terms such as first and second, etc. are only used to distinguish one entity or operation from another entity or operation, and do not necessarily require or imply any such actual relationship or order between these entities or operations. Moreover, the terms "include", "comprise" or any other variants thereof are intended to cover non-exclusive inclusion, so that a process, method, article or device including a series of elements includes not only those elements, but also other elements not explicitly listed, or also includes elements inherent to such process, method, article or device.

[0084] Finally, it should be noted that the above description is only a preferred embodiment of the present invention and is not intended to limit the present invention. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art can still modify the technical solutions described in the aforementioned embodiments or replace some of the technical features therein by equivalents. Any modification, equivalent replacement, improvement, etc. made within the spirit and principle of the present invention shall be included in the protection scope of the present invention.

Claims

1. A method for manufacturing a selectively gold-plated double-sided heat dissipation copper-based carrier board, characterized in that: The steps include: S1: Raw material preparation: Prepare AlN ceramic and copper sheet; S2: Pre-oxidation of copper sheet: pre-oxidizing the copper sheet to obtain a pre-oxidized copper sheet; S3: AlN ceramic evaporation: several pre-oxidized copper sheets obtained in S2 are placed horizontally on the mesh belt with the oxidized surface facing upward, and the AlN ceramic to be evaporated is placed vertically on the surface thereof for evaporation to obtain copper-containing AlN ceramic; S4: oxidation of copper-containing AlN ceramics: oxidizing the copper-containing AlN ceramics obtained in S3 to obtain copper ceramics; S5: primary sintering of copper porcelain: sintering the copper porcelain obtained in S4 once to obtain copper porcelain A; S6: Pattern transfer and slicing: the copper porcelain A obtained in S5 is subjected to pattern transfer, product cutting and slicing, and porcelain slice cutting and slicing in sequence to obtain porcelain slices; S7: performing secondary sintering on the ceramic sheet obtained in S6 to obtain a copper-based carrier plate; S8: performing selective gold plating on the copper-based substrate obtained in S7 to obtain a selective gold-plated double-sided heat dissipation copper-based substrate; In the S2, the process parameters of the pre-oxidation treatment are: annealing treatment at an oxygen content of 600-800 PPM, the annealing temperature zones include 1-11 temperature zones, which are: temperature zone 1 is 500-520°C, temperature zone 2 is 680-700°C, temperature zone 3 is 780-800°C, temperature zone 4 is 790-810°C, temperature zone 5 is 760-800°C, temperature zone 6 is 760-800°C, temperature zone 7 is 760-800°C, temperature zone 8 is 760-800°C, temperature zone 9 is 700-740°C, temperature zone 10 is 640-680°C, and temperature zone 11 is 620-660°C; In S4, the oxidation temperature of the copper-containing AlN ceramic is 1000-1100° C., and the oxidation time is 4-6 hours; In S5, the process parameters of the primary sintering are: the primary sintering includes 1 to 10 temperature zones, which are: temperature zone 1 is 770 to 790°C, temperature zone 2 is 900 to 910°C, temperature zone 3 is 1020 to 1030°C, temperature zone 4 is 1090 to 1100°C, temperature zone 5 is 1090 to 1100°C, temperature zone 6 is 1090 to 1100°C, temperature zone 7 is 1086 to 1094°C, temperature zone 8 is 1086 to 1094°C, temperature zone 9 is 1030 to 1040°C, and temperature zone 10 is 995 to 1005°C; In S7, the process parameters of the secondary sintering are: the secondary sintering includes 1 to 10 temperature zones, which are: temperature zone 1 is 775-785°C, temperature zone 2 is 900-910°C, temperature zone 3 is 1020-1030°C, temperature zone 4 is 1092-1100°C, temperature zone 5 is 1092-1100°C, temperature zone 6 is 1090-1097°C, temperature zone 7 is 1088-1094°C, temperature zone 9 is 1030-1040°C, and temperature zone 10 is 995-1005°C.

2. The method for manufacturing a selectively gold-plated double-sided heat dissipating copper-based carrier according to claim 1, characterized in that: In S3, the pre-oxidized copper sheet is pre-bent in both directions using a pre-bending machine before placement; when the AlN ceramic is vertically placed on the surface of the pre-oxidized copper sheet, the pre-oxidized copper sheet overlaps front and back by 4.5 to 5.5 mm.

3. The method for manufacturing a selectively gold-plated double-sided heat dissipating copper-based carrier according to claim 1, characterized in that: In the S3, the process parameters of the evaporation are: setting the 100mL flow meter to 5% oxygen flow rate and the belt speed to 8 inches / min; the evaporation includes 1 to 8 temperature zones, namely: temperature zone 1 is 720-740°C, temperature zone 2 is 820-840°C, temperature zone 3 is 905-925°C, temperature zone 4 is 940-960°C, temperature zone 5 is 930-970°C, temperature zone 6 is 930-970°C, temperature zone 7 is 930-970°C, and temperature zone 8 is 880-920°C.

4. The method for manufacturing a selectively gold-plated double-sided heat dissipating copper-based carrier according to claim 1, characterized in that: In S1, the specification of AlN ceramic is 138×190mm 2 , the specification of copper sheet is 132×184mm 2 .

5. The method for manufacturing a selectively gold-plated double-sided heat dissipating copper-based carrier according to claim 1, characterized in that: In S6, the pattern transfer includes film lamination, exposure, development, etching, and film stripping; the etching process parameters are: the etching temperature is 50±3°C, and the upper and lower spray pressures are 2.7±0.3kg / cm 2 and 2.2±0.4kg / cm 2 ; The solution used for the etching is 1.9±0.2N hydrochloric acid.

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