CN111328208A - Solution for electroless plating of gold on electroless nickel-gold plate - Google Patents
Solution for electroless plating of gold on electroless nickel-gold plate Download PDFInfo
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- CN111328208A CN111328208A CN202010195844.1A CN202010195844A CN111328208A CN 111328208 A CN111328208 A CN 111328208A CN 202010195844 A CN202010195844 A CN 202010195844A CN 111328208 A CN111328208 A CN 111328208A
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- palladium
- plate
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- oil
- production
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- H—ELECTRICITY
- H05—ELECTRIC TECHNIQUES NOT OTHERWISE PROVIDED FOR
- H05K—PRINTED CIRCUITS; CASINGS OR CONSTRUCTIONAL DETAILS OF ELECTRIC APPARATUS; MANUFACTURE OF ASSEMBLAGES OF ELECTRICAL COMPONENTS
- H05K3/00—Apparatus or processes for manufacturing printed circuits
- H05K3/22—Secondary treatment of printed circuits
- H05K3/26—Cleaning or polishing of the conductive pattern
Abstract
The invention discloses a solution for gold plating on a non-plated hole of a chemical nickel-gold plate, which comprises the following steps: adding a palladium removing agent into an oil removing cylinder in the nickel and gold depositing process, wherein a tank solution in the oil removing cylinder is a mixed solution consisting of an oil removing agent and the palladium removing agent, and the content of the palladium removing agent in the mixed solution is controlled to be 90-110 ml/L; after a solder mask is manufactured on a production board, the production board sequentially undergoes oil removal, water washing, microetching, water washing, acidity, water washing, presoaking, activation, post-soaking and water washing, wherein the oil removal process adopts an oil removal cylinder added with a palladium removal agent in the step S1 to carry out oil removal treatment, and palladium in non-plated holes on the production board is removed; and then carrying out chemical nickel and gold deposition treatment on the production plate. The method can effectively remove the metal palladium in the non-plated holes on the plate while reducing the palladium removing process, solves the problem of gold plating on the non-plated holes, improves the production efficiency, reduces the production cost, and is simultaneously suitable for the production of the positive plate and the negative plate.
Description
Technical Field
The invention relates to the technical field of printed circuit board manufacturing, in particular to a solution for electroless plating gold on a chemical nickel gold plate.
Background
The outer layer etching of the circuit board industry is divided into positive etching (manufacturing method of a positive plate) and negative etching (manufacturing method of a negative plate), wherein:
positive etching: after alkaline etching, the production plate has a special palladium removing procedure to remove metal palladium in the holes and prevent gold from being raised in the gold precipitation process.
Negative etching: the production plate is subjected to acid etching, palladium residual in holes is subjected to poisoning effect by acid etching solution, and after etching, the palladium is not required to be removed independently through a palladium removing procedure, and then gold precipitation is carried out.
The two methods described above have the following drawbacks:
(1) the production method comprises the following steps of (1) additionally adding a palladium removing process between alkaline etching and chemical nickel and gold deposition, and spraying and cleaning a production plate by using a palladium removing agent to remove metal palladium in non-plated holes, wherein the added palladium removing process can influence the production efficiency of the plate, the palladium removing agent is seriously wasted in a spraying mode, the monthly expenditure cost of the palladium removing agent is about 15000 yuan, the production cost is greatly improved, and the sprayed palladium removing agent is separately collected, so that the waste liquid treatment pressure is increased;
(2) the negative etched plate has no palladium removing step, so that gold is deposited in non-plated holes after chemical gold deposition, the length of production equipment needs to be increased if the palladium removing step is added after the acid etching step, and the periodic replacement of the palladium removing agent increases the labor intensity and cost and has influence on sewage treatment.
Disclosure of Invention
Aiming at the problem that the existing step plate has the defects, the invention provides a method for solving the problem of gold plating on the non-plated hole of the chemical nickel gold plate.
In order to solve the technical problem, the invention provides a method for solving the problem of gold plating on the non-plated hole of a chemical nickel-gold plate, which comprises the following steps:
s1, adding a palladium removing agent into the oil removing cylinder in the nickel and gold depositing process, wherein the bath solution in the oil removing cylinder is a mixed solution consisting of the oil removing agent and the palladium removing agent, and the content of the palladium removing agent in the mixed solution is controlled to be 90-110 ml/L;
s2, after the solder mask is manufactured on the production board, the production board sequentially goes through the working procedures of oil removal, water washing, micro-etching, water washing, acidity, water washing, pre-dipping, activation, post-dipping and water washing, wherein the oil removal working procedure adopts an oil removal cylinder which is added with a palladium removal agent in the step S1 to carry out oil removal treatment, and palladium in non-plated holes on the production board is removed;
and S3, and performing chemical nickel and gold deposition treatment on the production plate.
Further, in step S1, the palladium removing agent is composed of 0.4-0.8mol/L hydrochloric acid, 50-80g/L thiourea and the balance of water.
Further, in step S2, the temperature of the mixed solution in the degreasing cylinder is controlled to 40 to 60 ℃.
Further, in step S2, the production board needs to be soaked in the oil removing cylinder for 4-6min during oil removing treatment.
Further, in step S2, 20-30ml of a palladium removing agent is added to each square meter of the production board.
Further, in step S2, the frequency of replacement of the mixed solution in the oil removal cylinder is 1 time/half month.
Furthermore, the production board is a core board, and the core board is sequentially subjected to the processes of drilling, copper deposition, full-board electroplating and outer-layer circuit manufacturing before the solder mask layer is manufactured.
Furthermore, the production board is a multilayer board formed by pressing an inner core board and an outer copper foil into a whole through a prepreg, and the procedures of drilling, copper deposition, full-board electroplating and outer-layer circuit manufacturing are sequentially carried out on the multilayer board before the solder mask is manufactured.
Compared with the prior art, the invention has the following beneficial effects:
the method of the invention adds the palladium removing agent into the oil removing cylinder in the nickel and gold depositing process to be mixed with the oil removing agent, so that the oil removing agent has oil removing capability and can remove the metal palladium in the non-plated hole, and the oil removal treatment of the plate in the oil removal cylinder before the nickel and the gold are deposited is the original necessary working procedure, so the method of the invention does not add extra working procedures, therefore, the method of the invention can effectively remove the metal palladium in the non-plated hole on the plate while reducing the palladium removing process, solves the problem of gold on the non-plated hole, reduces the rework problem after gold is applied on the non-plated hole in the prior method, improves the production efficiency and the quality of nickel and gold deposition, does not have the waste condition by adopting the immersion method to remove the palladium agent, reduces the production cost, and because the nickel and gold deposition of the positive plate or the negative plate needs to pass through the oil cylinder, the method can be simultaneously suitable for the production of the positive plate and the negative plate; the content of the palladium removing agent in the mixed solution consisting of the oil removing agent and the palladium removing agent in the oil removing cylinder is controlled to be 90-110ml/L, namely the content of the palladium removing agent is controlled to be about 10% of the mixed solution, so that the oil removing effect cannot be influenced by adding excessive palladium removing agent, the palladium removing effect cannot be influenced by adding too little palladium removing agent, and the good oil removing and palladium removing quality is ensured; in addition, 20-30ml of the palladium removing agent is added into the oil removing cylinder according to each square meter of the production plate, so that the content of the palladium removing agent is kept in a required range, and the problem that the palladium removing agent is poor in later-stage palladium removing effect due to content reduction caused by reaction of the palladium removing agent and palladium in the palladium removing process is avoided.
Detailed Description
In order to more fully understand the technical contents of the present invention, the technical solutions of the present invention will be further described and illustrated with reference to specific embodiments.
Example 1
The method for manufacturing a circuit board shown in this embodiment can effectively solve the problem of gold plating on non-plated holes during electroless nickel-gold plating, and sequentially includes the following processing steps:
(1) cutting, namely cutting a core plate according to the dimension of the jointed plate of 320mm × 420mm, wherein the thickness of the core plate is 0.5mm (the thickness is the thickness without copper), and the thickness of the outer copper surface of the core plate is 0.5 OZ.
(2) And manufacturing an inner layer circuit (negative film process): coating a photosensitive film on the core plate by using a vertical coating machine, controlling the film thickness of the photosensitive film to be 8 mu m, and completing the exposure of an inner layer circuit by using 5-6 exposure rulers (21 exposure rulers) by using a full-automatic exposure machine; etching the inner layer, etching an inner layer circuit on the exposed and developed core plate, wherein the line width of the inner layer is measured to be 3 mil; and (4) inner layer AOI, and then, detecting defects of an inner layer circuit, such as open short circuit, circuit notch, circuit pinhole and the like, and performing defect scrapping treatment, wherein a defect-free product is discharged to the next flow.
(3) And pressing: the browning speed is that the outer copper foil, the PP sheet, the core plate, the PP sheet and the outer copper foil are sequentially laminated according to the thickness of the bottom copper, and then the production plate is formed by pressing under proper laminating conditions according to the characteristics of the plate.
(4) And outer layer drilling, namely drilling on the production board by using the drilling data, wherein the drilled holes comprise non-through holes (namely non-plated holes) and through holes.
(5) And depositing copper, namely metalizing the holes on the production board, and testing the backlight to 10 levels, wherein the thickness of the deposited copper in the holes is 0.5 mu m.
(6) And electroplating the whole plate: the plate was electroplated for 20min at a current density of 1.8 ASD.
(7) And manufacturing an outer layer circuit (positive process): transferring an outer layer pattern, completing outer layer line exposure by using a full-automatic exposure machine and a positive film line film with 5-7 exposure rulers (21 exposure rulers), and forming an outer layer line pattern on a production board through development; and (3) outer layer pattern electroplating, then respectively plating copper and tin on the production plate, wherein the copper plating is carried out for 60min by using a current density of 1.8ASD, the tin plating is carried out for 10min by using a current density of 1.2ASD, the tin thickness is 3-5 mu m, then sequentially stripping, etching and stripping the tin, etching an outer layer circuit and an outer layer AOI on the production plate, then checking the defects of the outer layer circuit, such as open short circuit, circuit notch, circuit pinhole and the like, carrying out defective scrapping treatment, and discharging the product without defects to the next process.
(8) Solder resist and silk screen printing of characters: according to the prior art and according to design requirements, a solder mask is made on a production board and characters are silk-screened.
(9) And surface treatment: according to the prior art and according to the design requirement, uniformly depositing nickel gold with certain required thickness on the copper surface of the solder-resisting windowing position through a chemical principle; the method specifically comprises the following steps:
a. firstly, adding a palladium removing agent into an oil removing cylinder in a nickel and gold precipitation process, so that a tank solution in the oil removing cylinder is a mixed solution consisting of the oil removing agent and the palladium removing agent, and the content of the palladium removing agent in the mixed solution is controlled to be 90-110ml/L, preferably 100ml/L, namely the content of the palladium removing agent accounts for 10 vol% of the mixed solution; the palladium removing agent consists of 0.4-0.8mol/L hydrochloric acid, 50-80g/L thiourea and the balance of water.
b. The production plate sequentially undergoes oil removal, water washing, microetching, water washing, acidity, water washing, presoaking, activation, post-soaking and water washing procedures, wherein the oil removal procedure adopts an oil removal cylinder added with the palladium removal agent in the step a to carry out oil removal treatment, and metal palladium in non-plated holes on the production plate is removed by the palladium removal agent in the mixed solution during the oil removal treatment; in the above, during oil removal treatment, the production plate needs to be soaked in the oil removing cylinder for 4-6min, and the temperature of the mixed solution in the oil removing cylinder is controlled at 40-60 ℃; adding 20-30ml of palladium removing agent into the oil removing cylinder according to each square meter of production plate, namely adding 20-30ml of palladium removing agent into the mixed solution every square meter of production plate, and ensuring that the content of the palladium removing agent in the mixed solution is always kept within the required control range (namely 90-110 ml/L); the replacement frequency of the mixed solution in the oil removing cylinder is changed from 1 time per week to 1 time per half month, the replaced waste liquid is discharged into an independent collecting barrel used for collecting the oil removing agent in the environment-friendly station, and the waste liquid is periodically transported and treated, so that the palladium removing agent and the oil removing agent are collected together, the process of separately collecting the palladium removing agent is reduced, and the pressure for treating the waste liquid is reduced.
c. And then carrying out chemical nickel deposition and chemical gold deposition treatment on the production plate.
(10) And forming: according to the prior art and according to the design requirement, the circuit board is manufactured.
(11) And electrical performance testing: and detecting the electrical performance of the circuit board, and enabling the circuit board qualified in detection to enter the next processing link.
(12) And final inspection: and (4) respectively measuring the appearance, the thickness of the hole copper, the thickness of the medium layer, the thickness of the green oil, the thickness of the inner layer copper and the like of the finished product, and discharging the qualified product.
Example 2
The method for manufacturing a circuit board shown in this embodiment can effectively solve the problem of gold plating on non-plated holes during electroless nickel-gold plating, and sequentially includes the following processing steps:
(1) cutting, namely cutting a core plate according to the dimension of the jointed plate of 320mm × 420mm, wherein the thickness of the core plate is 0.5mm (the thickness is the thickness without copper), and the thickness of the outer copper surface of the core plate is 0.5 OZ.
(2) And drilling, namely drilling on the core plate by using the drilling data, wherein the drilled holes comprise non-through holes (namely non-plated holes) and through holes.
(3) And depositing copper, namely metalizing the holes on the core board, and testing the backlight to 10 levels, wherein the thickness of the deposited copper in the holes is 0.5 mu m.
(4) And electroplating the whole plate: the plate was electroplated for 20min at a current density of 1.8 ASD.
(5) And manufacturing an inner layer circuit (negative film process): coating a photosensitive film on the core plate by using a vertical coating machine, controlling the film thickness of the photosensitive film to be 8 mu m, and completing the exposure of an inner layer circuit by using 5-6 exposure rulers (21 exposure rulers) by using a full-automatic exposure machine; etching the inner layer, etching an inner layer circuit on the exposed and developed core plate, wherein the line width of the inner layer is measured to be 3 mil; and (4) inner layer AOI, and then, detecting defects of an inner layer circuit, such as open short circuit, circuit notch, circuit pinhole and the like, and performing defect scrapping treatment, wherein a defect-free product is discharged to the next flow.
(6) Solder resist and silk screen printing of characters: and manufacturing a solder mask layer on the core board according to the design requirements and silk-screen printing characters according to the prior art.
(7) And surface treatment: according to the prior art and according to the design requirement, uniformly depositing nickel gold with certain required thickness on the copper surface of the solder-resisting windowing position through a chemical principle; the method specifically comprises the following steps:
a. firstly, adding a palladium removing agent into an oil removing cylinder in a nickel and gold precipitation process, so that a tank solution in the oil removing cylinder is a mixed solution consisting of the oil removing agent and the palladium removing agent, and the content of the palladium removing agent in the mixed solution is controlled to be 90-110ml/L, preferably 100ml/L, namely the content of the palladium removing agent accounts for 10 vol% of the mixed solution; the palladium removing agent consists of 0.4-0.8mol/L hydrochloric acid, 50-80g/L thiourea and the balance of water.
b. Then the core plate is sequentially subjected to oil removal, water washing, microetching, water washing, acidity, water washing, presoaking, activation, post-soaking and water washing procedures, wherein the oil removal procedure adopts an oil removal cylinder added with the palladium removal agent in the step a to carry out oil removal treatment, and metal palladium in non-plated holes on the production plate is removed by using the palladium removal agent in the mixed solution during the oil removal treatment; in the above, when oil removing treatment is carried out, the core plate needs to be soaked in the oil removing cylinder for 4-6min, and the temperature of the mixed solution in the oil removing cylinder is controlled at 40-60 ℃; adding 20-30ml of palladium removing agent into the oil removing cylinder according to each square meter of core plate, namely adding 20-30ml of palladium removing agent into the mixed solution every square meter of core plate is produced, and ensuring that the content of the palladium removing agent in the mixed solution is always kept within the required control range (namely 90-110 ml/L); the replacement frequency of the mixed solution in the oil removing cylinder is changed from 1 time per week to 1 time per half month, the replaced waste liquid is discharged into an independent collecting barrel used for collecting the oil removing agent in the environment-friendly station, and the waste liquid is periodically transported and treated, so that the palladium removing agent and the oil removing agent are collected together, the process of separately collecting the palladium removing agent is reduced, and the pressure for treating the waste liquid is reduced.
c. And then carrying out chemical nickel deposition and chemical gold deposition treatment on the core plate.
(8) And forming: according to the prior art and according to the design requirement, the circuit board is manufactured.
(9) And electrical performance testing: and detecting the electrical performance of the circuit board, and enabling the circuit board qualified in detection to enter the next processing link.
(10) And final inspection: and (4) respectively measuring the appearance, the thickness of the hole copper, the thickness of the medium layer, the thickness of the green oil, the thickness of the inner layer copper and the like of the finished product, and discharging the qualified product.
Through experiments, when the existing method is adopted for manufacturing, the gold-plating rework rate of the gold-deposition non-plated hole reaches 3%, and when the modified method in the embodiment 1 or 2 is adopted for manufacturing, the gold-plating phenomenon is only generated when the resin hole plugging process plate is manufactured, the rework rate is about 0.2%, and the cost of the palladium removing agent is reduced from 15000 yuan to 7000 yuan per month, so that the production cost is greatly reduced.
The technical solutions provided by the embodiments of the present invention are described in detail above, and the principles and embodiments of the present invention are explained herein by using specific examples, and the descriptions of the embodiments are only used to help understanding the principles of the embodiments of the present invention; meanwhile, for a person skilled in the art, according to the embodiments of the present invention, there may be variations in the specific implementation manners and application ranges, and in summary, the content of the present description should not be construed as a limitation to the present invention.
Claims (8)
1. A solution for gold plating on electroless nickel-gold plate holes is characterized by comprising the following steps:
s1, adding a palladium removing agent into the oil removing cylinder in the nickel and gold depositing process, wherein the bath solution in the oil removing cylinder is a mixed solution consisting of the oil removing agent and the palladium removing agent, and the content of the palladium removing agent in the mixed solution is controlled to be 90-110 ml/L;
s2, after the solder mask is manufactured on the production board, the production board sequentially goes through the working procedures of oil removal, water washing, micro-etching, water washing, acidity, water washing, pre-dipping, activation, post-dipping and water washing, wherein the oil removal working procedure adopts an oil removal cylinder which is added with a palladium removal agent in the step S1 to carry out oil removal treatment, and palladium in non-plated holes on the production board is removed;
and S3, and performing chemical nickel and gold deposition treatment on the production plate.
2. The method as claimed in claim 1, wherein the step S1, the palladium removing agent comprises 0.4-0.8mol/L hydrochloric acid, 50-80g/L thiourea and the balance water.
3. The method according to claim 1, wherein the temperature of the mixed solution in the degreasing cylinder is controlled to 40-60 ℃ during the degreasing process in step S2.
4. The method according to claim 3, wherein in step S2, the production board is immersed in the oil removing cylinder for 4-6min during the oil removing process.
5. The method of claim 1, wherein in step S2, 20-30ml of palladium removing agent is added to each square meter of production board.
6. The method of claim 1, wherein the frequency of replacing the mixed solution in the oil cylinder is 1/half month.
7. The method as claimed in claim 1, wherein the production board is a core board, and the steps of drilling, copper deposition, full-board electroplating and outer-layer circuit fabrication are sequentially performed on the core board before the solder mask is fabricated.
8. The method for electroless gold plating of holes in a electroless nickel-gold plate according to claim 1, wherein the production plate is a multi-layer plate formed by laminating an inner core plate and an outer copper foil together by a prepreg, and the steps of drilling, copper deposition, full-plate electroplating and outer circuit fabrication are sequentially performed on the multi-layer plate before the solder mask is fabricated.
Priority Applications (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010195844.1A CN111328208A (en) | 2020-03-19 | 2020-03-19 | Solution for electroless plating of gold on electroless nickel-gold plate |
Applications Claiming Priority (1)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| CN202010195844.1A CN111328208A (en) | 2020-03-19 | 2020-03-19 | Solution for electroless plating of gold on electroless nickel-gold plate |
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| CN111328208A true CN111328208A (en) | 2020-06-23 |
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| Application Number | Title | Priority Date | Filing Date |
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| CN202010195844.1A Pending CN111328208A (en) | 2020-03-19 | 2020-03-19 | Solution for electroless plating of gold on electroless nickel-gold plate |
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Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3162512A (en) * | 1961-03-21 | 1964-12-22 | Engelhard Ind Inc | Immersion plating with noble metals and the product thereof |
| CN1055961A (en) * | 1990-04-14 | 1991-11-06 | 廖仲威 | Efficient detergent for degreasing and rust removal at ordinary temp |
| CN102105020A (en) * | 2009-12-16 | 2011-06-22 | 北大方正集团有限公司 | Making method for printed-circuit boards and palladium removing device for printed-circuit boards |
| CN103249254A (en) * | 2013-04-22 | 2013-08-14 | 胜宏科技（惠州）股份有限公司 | Method of removing palladium in NPTHs of PCB |
| CN103945644A (en) * | 2014-05-13 | 2014-07-23 | 张伯平 | Flat circuit board and manufacturing method thereof |
-
2020
- 2020-03-19 CN CN202010195844.1A patent/CN111328208A/en active Pending
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3162512A (en) * | 1961-03-21 | 1964-12-22 | Engelhard Ind Inc | Immersion plating with noble metals and the product thereof |
| CN1055961A (en) * | 1990-04-14 | 1991-11-06 | 廖仲威 | Efficient detergent for degreasing and rust removal at ordinary temp |
| CN102105020A (en) * | 2009-12-16 | 2011-06-22 | 北大方正集团有限公司 | Making method for printed-circuit boards and palladium removing device for printed-circuit boards |
| CN103249254A (en) * | 2013-04-22 | 2013-08-14 | 胜宏科技（惠州）股份有限公司 | Method of removing palladium in NPTHs of PCB |
| CN103945644A (en) * | 2014-05-13 | 2014-07-23 | 张伯平 | Flat circuit board and manufacturing method thereof |
Non-Patent Citations (1)
| Title |
|---|
| 刘东，罗红军，朱拓: ""碱性蚀刻线产能倍增方法的研究和实施"", 《印制电路信息》 * |
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Application publication date: 20200623 |
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