CN111876799A - A kind of composition suitable for backplane hole metallization and hole metallization method thereof - Google Patents

Abstract

The present invention relates to the field of electroplating, and more particularly, the present invention relates to a metallization composition for backplane holes and a hole metallization method thereof, comprising 30,000-350,000 ppm copper ions, 5,000-350,000 ppm inorganic acids, and 1-10,000 ppm cyclic Polymers formed by the polymerization of oxides and/or alcohols. The hole metallization composition provided by the invention can improve the distribution of hole copper and surface copper thickness, reduce material consumption, can use a higher current density in reverse pulse plating, increase the productivity of the electroplating line, the plating layer is fine and compact, and has good It has good ductility and low internal stress, and has good thermal shock resistance. It is especially suitable for the electroplating of high aspect ratio printed circuit board through holes, which can improve the deep plating ability of high aspect ratio printed circuit board through holes copper plating and improve production. efficiency, thereby improving the copper plating quality of high aspect ratio printed circuit boards, ensuring product quality and reliability.

Description

A kind of composition suitable for backplane hole metallization and hole metallization method thereof

technical field

The present invention relates to the field of electroplating, and more particularly, the present invention relates to a composition suitable for backplane hole metallization and a hole metallization method thereof.

Background technique

The backplane, also known as the "backplane", is a high-end PCB product and is mainly used in communication equipment, supercomputers, military base stations and other very important equipment. All daughter boards or user boards are connected through the backplane to achieve their working functions. Therefore, functionally speaking, the backplane is the key core component of these devices, not only responsible for switching, radio frequency, power supply and other single boards. Bearing function, but also provide signal transmission for switching stations and network equipment, can be called the "nerve center" of the electronic system.

Hole metallization refers to plating a layer of copper on the inner walls of the through holes between the top and bottom layers of a circuit board so that the top and bottom layers of the circuit board are connected to each other. The hole metallization of the circuit board is usually achieved by traditional DC electroplating. However, the backplane has a high number of layers (up to about 60 layers), super large size (up to 762mm × 1300mm), super thick (4mm ~ 13mm), super heavy (about 20Kg per sheet), fine lines and spacing, and board thickness. The aperture ratio (16:1~20:1) and other characteristics make the hole metallization processing technology more difficult, especially for the deep plating ability and copper plating reliability of high aspect ratio holes. The traditional DC copper plating technology cannot meet the requirements of high aspect ratio circuit board hole metallization due to insufficient deep plating ability, especially for circuit boards with assembly requirements for through holes. .

SUMMARY OF THE INVENTION

In view of some problems existing in the prior art, a first aspect of the present invention provides a pore metallization composition, which comprises 30,000-350,000 ppm copper ions, 5,000-350,000 ppm inorganic acids, 1-10,000 ppm composed of epoxides and/or A polymer made from the polymerization of alcohols.

As a preferred technical solution of the present invention, the polymers obtained by polymerizing epoxides and/or alcohols include polypropylene glycol, polyethylene glycol, ethylene oxide-propylene oxide copolymer, butanol - At least one of ethylene oxide-propylene oxide copolymers.

As a preferred technical solution of the present invention, the weight average molecular weight of the butanol-ethylene oxide-propylene oxide copolymer is 100-100,000.

As a preferred technical solution of the present invention, the weight average molecular weight of the butanol-ethylene oxide-propylene oxide copolymer is 500-10,000.

As a preferred technical solution of the present invention, the pore metallization composition further includes 0.001ppm to 1000ppm of brightener; the brightener includes N,N-dimethyl-dithiocarbamic acid-(3-sulfonic acid) propyl) ester, 3-mercapto-propyl sulfonic acid-(3-sulfopropyl) ester, 3-mercapto-propyl sulfonic acid and its corresponding salt, dithio-O-ethyl ester-s-ester , 3-mercapto-1-propane sulfonate, bissulfopropyl disulfide and its corresponding salt, 3-(benzothiazolyl-S-thio) propyl sulfonate, pyridinium propyl sulfonate Betaine, 1-Sodium-3-mercaptopropane-1-sulfonate, N,N-Dimethyl-dithiocarbamate-(3-sulfoethyl)ester, N,N-Dimethyldisulfide Sodium carboxamide propane sulfonate, 3-mercapto-ethylpropyl sulfonate-(3-sulfoethyl) ester, 3-mercapto-ethyl sulfonate, carbonate-dithio-O-ethyl ester-S -Ester, 3-mercapto-1-ethanesulfonate, bissulfoethyl disulfide and its corresponding salt, 3-(benzothiazolyl-S-thio)ethanesulfonate, pyridinium ethyl At least one of sulfobetaine and 1-sodium-3-mercaptoethane-1-sulfonate.

As a preferred technical solution of the present invention, the pore metallization composition further comprises 1-5000 ppm leveling agent; the leveling agent is a heterocyclic compound and/or an ethylene oxide copolymer; the epoxy Ethane copolymers are polymers of heterocyclic compounds and ethylene oxide; the heterocyclic compounds have the following structure:

The Xe and Rn may be the same or different, and are respectively selected from hydrogen, C ₁ -C ₁₀ alkyl, alkoxy, cyano, hydroxyl, amino, carboxyl, mercapto, sulfonic acid, nitro, amido, alkene One or more of alkynyl, alkynyl and azo.

As a preferred technical solution of the present invention, the R ₁ and R ₂ may be the same or different, and are respectively selected from hydrogen, substituted or unsubstituted C ₁ -C ₁₂ alkyl, and substituted or unsubstituted C ₂ -C One or more of C ₁₂ alkenyl, substituted or unsubstituted aryl, cyano, hydroxyl, amino, carboxyl, mercapto, sulfonic, nitro, amido, alkenyl, alkynyl, and azo.

As a preferred technical solution of the present invention, the B and Y may be the same or different, and are selected from any of C, N, P, O, and S, respectively.

As a preferred technical solution of the present invention, the substituted aryl group is a C ₁ -C ₄ alkyl and/or hydroxy substituted aryl group.

As a preferred technical solution of the present invention, the aryl group is selected from any one of phenyl, xylyl and naphthyl.

A second aspect of the present invention provides a hole metallization method, which includes: placing the hole metallization composition on a printed circuit board having a plurality of through holes at 25-60° C., and performing copper plating by using a reverse pulse method , 120 ~ 225min.

As a preferred technical solution of the present invention, the forward and reverse current density ratio of the reverse pulse method is 1:(1.5-3.5).

Compared with the prior art, the present invention has the following beneficial effects:

The hole metallization composition provided by the invention can improve the distribution of hole copper and surface copper thickness, reduce material consumption, can use a higher current density in reverse pulse plating, increase the productivity of the electroplating line, the plating layer is fine and compact, and has good It has good ductility and low internal stress, and has good thermal shock resistance. It is especially suitable for the electroplating of high aspect ratio printed circuit board through holes, which can improve the deep plating ability of high aspect ratio printed circuit board through holes copper plating and improve production. efficiency, thereby improving the copper plating quality of high aspect ratio printed circuit boards, ensuring product quality and reliability.

Description of drawings

Figure 1 is a schematic cross-sectional view of a printed circuit board through hole;

A1, A2, A3, A4-the plating thickness of the surface copper of the through-hole section of the printed circuit board; B1, B2, B3, B4-the plating thickness of the hole copper of the through-hole section of the printed circuit board; C1, C2-printing Thickness of copper plating in the middle of the hole in the through-hole section of the circuit board

Detailed ways

The present invention is described below through specific embodiments, but is not limited to the specific examples given below.

Unless clearly stated otherwise, the following abbreviations in this specification have the following meanings:

min: minutes; ms: milliseconds; um: microns; ASD: amperes per square decimeter; ASF: amperes per square inch; AH: ampere hours; ppm: parts per million; ppb: parts per billion; °C: Celsius; g/L: grams/liter; A: ampere; dm: decimeter; DI: deionized; wt%: weight percent; Tg: glass transition temperature.

Aperture ratio of the through hole: the height of the through hole / the diameter of the through hole.

Throwability: The ability to deposit the same thickness in lower current density areas as in higher current density areas.

All amounts are weight percentages unless otherwise indicated. All numerical ranges are inclusive and combinable with each other in any order, and the sum of such numerical ranges is defined as 100%.

Hole metallization: Hole metallization refers to a process in which each layer of printed wires is plated with a layer of conductive metal on the insulating hole wall by electroless plating and electroplating in the hole to make them reliably connected to each other. The core problem of the double-sided printed board manufacturing process with metallized holes is the hole metallization process. The requirements for metallized holes are strict, requiring good mechanical toughness and electrical conductivity, the metallized copper layer is uniform and complete, and the thickness is between 5 and 10 μm. , No drilling chips, no cracks, hole resistance below 1000μΩ.

Hole copper: Hole copper is a hole with metallization requirements. A layer of copper is plated inside the hole by electroplating, so that both sides of the hole can be connected. This layer of copper in the hole is called hole copper.

Solder Mask Ink: It is an ink used in the soldering process.

DC: stands for direct current. "Direct Current" (Direct Current, referred to as DC), also known as "constant current".

AC: stands for alternating current. Alternating Current (abbreviated AC) refers to the alternating current whose direction of current changes periodically with time.

The mesoporous metallization compositions of the present invention are electroplating baths for hole metallization.

A first aspect of the present invention provides a pore metallization composition comprising 30,000-350,000 ppm of copper ions, 5,000-350,000 ppm of inorganic acids, and 1-10,000 ppm of polymers polymerized from epoxides and/or alcohols.

In one embodiment, the hole metallization composition further comprises 0.001 ppm to 1000 ppm of brightener.

In one embodiment, the pore metallization composition further includes 1 to 5000 ppm of a leveling agent.

In a preferred embodiment, the pore metallization composition includes 30,000-250,000 ppm copper ions, 80,000-270,000 ppm inorganic acids, 5-10,000 ppm polymers polymerized from epoxides and/or alcohols, 0.001 ppm ～500ppm brightener, 1～5000ppm leveling agent.

In a preferred embodiment, the pore metallization composition includes 30,000-250,000 ppm copper ions, 80,000-270,000 ppm inorganic acids, 5-10,000 ppm polymers polymerized from epoxides and/or alcohols, 0.05-270,000 ppm 10ppm brightener, 1～5000ppm leveling agent.

In a more preferred embodiment, the pore metallization composition comprises 40000ppm copper ions, 260060ppm inorganic acids, 1000 ppm polymers polymerized from epoxides and/or alcohols, 1ppm brightener, 20ppm levelling agent.

Copper ions

In one embodiment, the copper ions comprise at least one source of copper ions.

In one embodiment, the source of copper ions for copper ions includes, but is not limited to, water-soluble halides, nitrates, acetates, sulfates, and other organic or inorganic copper salts of copper.

Examples of the copper ion source include copper sulfate, copper sulfate pentahydrate, copper chloride, copper nitrate, copper hydroxide, copper sulfamate, and the like.

Preferably, the copper ion source is anhydrous copper sulfate.

Inorganic acid

In one embodiment, the inorganic acid includes, but is not limited to, sulfuric acid, hydrochloric acid, hydrofluoric acid, phosphoric acid, nitric acid, sulfamic acid, and alkylsulfonic acid.

Preferably, the inorganic acids are sulfuric acid and hydrochloric acid; further preferably, the concentration ratio of the sulfuric acid and hydrochloric acid is (4300-4500):1; more preferably, the concentration ratio of the sulfuric acid and hydrochloric acid is 4333:1.

Polymers made from epoxides and/or alcohols

In one embodiment, the polymer obtained by polymerizing epoxides and/or alcohols includes polypropylene glycol, polyethylene glycol, ethylene oxide-propylene oxide copolymer, butanol-ethylene oxide At least one of alkane-propylene oxide copolymers.

In one embodiment, the weight average molecular weight of the butanol-ethylene oxide-propylene oxide copolymer is 100-100,000.

Preferably, the weight average molecular weight of the butanol-ethylene oxide-propylene oxide copolymer is 500-10,000.

brightener

In one embodiment, the brighteners include, but are not limited to, N,N-dimethyl-dithiocarbamate-(3-sulfopropyl) ester, 3-mercapto-propylsulfonic acid-(3- Sulfopropyl) ester, 3-mercapto-propyl sulfonic acid and its corresponding sodium salt, dithiocarbonate-O-ethyl ester-S-ester and 3-mercapto-1-propane sulfonate, bissulfopropyl Disulfides and their corresponding salts, 3-(benzothiazolyl-s-thio)propylsulfonate, pyridinium propylsulfobetaine, 1-sodium-3-mercaptopropane-1-sulfonic acid Esters, N,N-Dimethyl-dithiocarbamate-(3-sulfoethyl)ester, Sodium N,N-Dimethyldithiocarbamate Propane Sulfonate, 3-Mercapto-ethylpropyl Sulfonate-(3-sulfoethyl)ester, 3-mercapto-ethylsulfonate, carbonate-dithio-O-ethylester-S-ester, 3-mercapto-1-ethanesulfonate, bisulfite Sulfoethyl disulfide and its corresponding salt, 3-(benzothiazolyl-S-thio)ethylsulfonate, pyridinium ethylsulfobetaine, 1-sodium-3-mercaptoethane- 1-sulfonic acid ester, 2-mercapto-ethanesulfonic acid and its corresponding sodium salt, 3-(benzothiazolyl-2-thio)propanesulfonic acid and its corresponding sodium salt, 3-mercaptopropane-1- Sulfonic acid and its corresponding salt, ethylenedithiodipropanesulfonic acid and its corresponding salt, bis(p-sulfophenyl)disulfide disodium salt, bis(ω-sulfobutyl)-disulfide Disodium salt, bis(ω-sulfohydroxypropyl)-disodium disulfide, bis(ω-sulfopropyl)-disodium disulfide, bis(ω-sulfopropyl)-disodium sulfide Salt, Methyl-(ω-sulfopropyl)-disulfide disodium salt, Methyl-(ω-sulfopropyl)-trisulfide disodium salt, O-ethyl-dithiocarbonic acid-S- (ω-sulfopropyl)-ester, potassium salt thioglycolic acid, phosphorothioate-O-ethyl-bis-(ω-sulfopropyl)-ester and its corresponding salt, phosphorothioate-tris(ω -Sulfopropyl)-ester and its corresponding salt, N,N-dimethyldithiocarbamate (3-sulfopropyl) ester and its corresponding salt, (O-ethyldithiocarbonic acid) )-S-(3-sulfopropyl)-ester and its corresponding salt, 3-[(amino-iminomethyl)-thio]-1-propanesulfonic acid, 3-(2-phenylthiazolyl At least one of thio)-1-propanesulfonic acid and its corresponding salt.

Preferably, the brightener includes N,N-dimethyl-dithiocarbamate-(3-sulfopropyl) ester, 3-mercapto-propylsulfonic acid-(3-sulfopropyl) ester, 3 -Mercapto-propyl sulfonic acid and its corresponding salts, dithiocarbonate-O-ethyl-s-ester, 3-mercapto-1-propane sulfonate, bissulfopropyl disulfide and its corresponding salts , 3-(benzothiazolyl-S-thio)propyl sulfonate, pyridinium propyl sulfobetaine, 1-sodium-3-mercaptopropane-1-sulfonate, N,N-dimethyl Ethyl-dithiocarbamate-(3-sulfoethyl) ester, Sodium N,N-dimethyldithiocarboxamide propanesulfonate, 3-mercapto-ethylpropylsulfonic acid-(3-sulfoethyl) base) ester, 3-mercapto-ethyl sulfonate, carbonate-dithio-O-ethyl ester-S-ester, 3-mercapto-1-ethane sulfonate, bissulfoethyl disulfide and its At least one of the corresponding salts, 3-(benzothiazolyl-s-thio)ethylsulfonate, pyridinium ethylsulfobetaine, 1-sodium-3-mercaptoethane-1-sulfonate more preferably, the brightening agent is bissulfopropyl disulfide and/or the corresponding salt of bissulfopropyl disulfide.

leveling agent

In one embodiment, the leveling agent is a heterocyclic compound and/or an ethylene oxide copolymer; the ethylene oxide copolymer is a polymer of a heterocyclic compound and ethylene oxide; the heterocyclic compound Cyclic compounds have the following structures:

The Xe and Rn may be the same or different, and are respectively selected from hydrogen, C ₁ -C ₁₀ alkyl, alkoxy, cyano, hydroxyl, amino, carboxyl, mercapto, sulfonic acid, nitro, amido, alkene One or more of alkynyl, alkynyl and azo.

Examples of C ₁ -C ₁₀ alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n-pentyl, 2-pentyl, 3-pentyl , 2-(2-methyl)butyl, 2-(2,3-dimethyl)butyl, 2-(2-methyl)pentyl, neopentyl, etc.

In one embodiment, the R ₁ and R ₂ may be the same or different, and are respectively selected from hydrogen, substituted or unsubstituted C ₁ -C ₁₂ alkyl, and substituted or unsubstituted C ₂ -C ₁₂ alkenyl , one or more of substituted or unsubstituted aryl, cyano, hydroxyl, amino, carboxyl, mercapto, sulfonic acid, nitro, amide, alkenyl, alkynyl, and azo groups.

The substituted aryl group in the present invention is a C ₁ -C ₄ alkyl and/or hydroxy substituted aryl group.

The substituted or unsubstituted aryl group may be exemplified by phenyl, tolyl, xylyl, hydroxytolyl, phenol, naphthyl, furyl, thiophenyl and the like.

Preferably, the aryl group is phenyl, xylyl or naphthyl.

Substituted or unsubstituted C ₁ -C ₁₂ alkyl groups include methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, n-pentyl, 2-pentyl , 3-pentyl, 2-(2-methyl)butyl, 2-(2,3-dimethyl)butyl, 2-(2-methyl)pentyl, neopentyl, hydroxymethyl, hydroxyethyl, hydroxypropyl, cyclopentyl, hydroxycyclopentyl, cyclopentylmethyl, cyclopentylethyl, cyclohexyl, cyclohexylmethyl, hydroxycyclohexyl, benzyl, phenethyl, naphthyl Methyl, tetrahydronaphthyl, tetrahydronaphthylmethyl, etc.

Substituted or unsubstituted C ₂ -C ₁₂ alkenyl groups include allyl, styryl, cyclopentenyl, cyclopentenylmethyl, cyclopentenylethyl, cyclohexenyl, cyclohexyl Alkenylmethyl, indenyl, etc.

In one embodiment, the B and Y may be the same or different, and are selected from any of C, N, P, O, and S, respectively.

The preparation method of the ethylene oxide copolymer of the present invention can be conventionally selected by those skilled in the art.

A second aspect of the present invention provides a hole metallization method, which includes: placing the hole metallization composition on a printed circuit board having a plurality of through holes at 25-60° C., and performing copper plating by using a reverse pulse method .

In one embodiment, the hole metallization method includes placing the hole metallization composition on a printed circuit board with a plurality of through holes at 25-60° C. for 20-200 minutes, and performing plating by a reverse pulse method. Copper, the electroplating time is 120 ~ 225min.

Preferably, the hole metallization method includes placing the hole metallization composition on a printed circuit board with a plurality of through holes at 25-40° C. for 150 minutes, and performing copper plating by a reverse pulse method.

In an embodiment, the forward and reverse current density ratio of the reverse pulse is 1:(1.5˜3.5).

In an embodiment, the power supply reverse current time of the reverse pulse is 0.5-1.5s; preferably, the power supply reverse current time of the reverse pulse is 1s.

In the present invention, the method for placing the hole metallization composition on the printed circuit board with a plurality of through holes is not particularly limited, and the methods may include immersing or immersing the printed circuit board in the hole metallizing composition, placing the The hole metallization composition is sprayed onto the printed circuit board, and the hole metallization composition is placed on the printed circuit board using a sprayer.

In one embodiment, the printed circuit board is plated with an electroless copper layer, so that the electroless copper plating is adjacent to the surface of the printed circuit board and the walls of the through holes.

Preferably, the thickness of the electroless plating layer is 0.25-6 um; more preferably, the thickness of the electroless plating layer is 0.25-3 um.

In one embodiment, an electroplating layer is further plated on the electroless plating layer.

Preferably, the thickness of the electroplated copper layer on the electroless copper layer is 0.5-15um; further preferably, the thickness of the electroplated copper layer on the electroless copper layer is 1-10um; more preferably, the electroless copper layer has a thickness of 1-10um. The thickness of the electroplated copper layer on the copper layer is 1-5um.

In one embodiment, the thickness of the printed circuit board is 0.5-10 mm.

In one embodiment, the vias extend across the width of the printed circuit board.

Preferably, the length of the through hole is 2˜6 mm.

Preferably, the diameter of the through hole is 100-1000um; more preferably, the diameter of the through-hole is 100-500um.

In one embodiment, the material of the printed circuit board includes at least one of thermosetting resin, thermoplastic resin, and fiber.

Thermoplastic resins include but are not limited to acetal resins, acrylic resins, cellulosic resins, polyethers, nylon, polyethylene, polystyrene, styrene blends, polycarbonate, polychlorotrifluoroethylene, vinyl polymers .

The cellulose resin may be exemplified by cellulose propionate, cellulose acetate butyrate, cellulose nitrate and the like.

The styrene blend may be exemplified by acrylonitrile styrene copolymer, acrylonitrile-butadiene-styrene copolymer, and the like.

The vinyl polymer can be exemplified by vinyl acetate, vinyl alcohol, vinyl butyral, vinyl chloride, vinyl chloride-acetate copolymer, vinylidene chloride, vinyl formaldehyde, and the like.

Thermosetting resins include, but are not limited to, allyl phthalate, furan, melamine-formaldehyde, phenol-formaldehyde copolymers, phenol-furfural copolymers.

In one embodiment, the thermosetting resin further comprises butadiene acrylonitrile copolymer, acrylonitrile-butadiene-styrene copolymer, polyacrylate, silicone resin, urea-formaldehyde, epoxy resin, allyl At least one of base resin, glycerol phthalate, polyester.

In one embodiment, the material of the printed circuit board includes low Tg resin or high Tg resin.

Low Tg resins: resins with Tg below 160°C.

High Tg resin: A resin with a Tg higher than 160°C.

High Tg resins include but are not limited to polytetrafluoroethylene, polytetrafluoroethylene blends, epoxy resins, bismaleimide/triazine, epoxy resins, epoxy/polyphenylene oxide resins, propylene Nitrile butadiene styrene, polycarbonate, polyphenylene oxide, polyphenylene oxide, polyphenylene sulfide, polysulfone, polyamide, polyester, polyetherketone, liquid crystal polymer, polyurethane, polyetherimide amine.

The polytetrafluoroethylene blends include, but are not limited to, PTFE, polyphenylene oxide, and cyanate esters.

The polyester includes, but is not limited to, polyethylene terephthalate, polybutylene terephthalate.

Those skilled in the art can make routine choices for the electroplating process described in the present invention.

The solvent of the metallization composition of the present invention is deionized water.

Example

Hereinafter, the present invention will be described in more detail by means of examples, but it should be understood that these examples are merely illustrative and not restrictive. Unless otherwise stated, the raw materials used in the following examples are all commercially available.

Example 1

Embodiment 1 of the present invention provides a pore metallization composition, which includes copper ions, inorganic acids, polymers polymerized from epoxides and/or alcohols, leveling agents, and brightening agents.

The copper ion source is copper sulfate pentahydrate; the inorganic acid is sulfuric acid and hydrochloric acid, and the polymer formed by the polymerization of epoxides and/or alcohols is an ethylene oxide-propylene oxide copolymer. From BASF, the trade name is PluronicRPE2520; the leveling agent is carboxypyridine/ethylene oxide copolymer and carboxypyrrole/ethylene oxide copolymer, and the carboxypyridine/ethylene oxide copolymer is 100mmol of 1,4 - Butanediol diglycidyl ether, 25 mmol of carboxypyridine were added to a round bottom reaction flask at room temperature, followed by 30 ml of deionized water, the initially formed white suspension finally disappeared as the reaction temperature increased and Converted to a phase separated mixture. The resulting reaction mixture was heated using an oil bath set at 98°C for 2 hours. After adding 2 ml of concentrated sulfuric acid to the reaction flask, the solution turned into a transparent pale yellow. The mixture was heated for an additional 3 hours and stirred at room temperature for an additional 8 hours. The resulting amber reaction product was transferred to a volumetric flask, rinsed with 0.5 wt% sulfuric acid and diluted. The reaction product solution can be used without further purification; the CAS number of the carboxypyridine is 59-67-6, namely 3-pyridinecarboxylic acid; the brightener is bissulfopropyl disulfide and its sodium salt and Sodium N,N-dimethyldithiocarboxamide propane sulfonate, the bissulfopropyl disulfide and its sodium salt were purchased from Jiangsu Mengde and Shenzhen Aoxinyuan.

The specific embodiment of the preparation method of the carboxypyrrole/ethylene oxide copolymer is the same as the carboxypyrrole/ethylene oxide copolymer, the difference is that the carboxypyrrole is replaced with carboxypyrrole, and the CAS number of the carboxypyrrole is as 1898-66-4.

The concentration composition of the porous metal composition is as follows:

The hole metallization method includes: placing the hole metallization composition on a printed circuit board having a plurality of through holes at 25° C., and performing copper plating by a reverse pulse method.

The steps of the electroplating are as follows:

1. Add potion

a. Add 2/3 volume of DI water;

b. Turn on the circulation, filtration and temperature control system;

c. Slowly add sulfuric acid, note that adding sulfuric acid will generate heat, so it needs to be added in stages, and the temperature in the bath cannot exceed 50 °C;

d. Add copper sulfate;

e. Hang the titanium basket with the titanium basket bag and the copper balls installed;

f. Supplement the water level, analyze and adjust the sulfuric acid, copper sulfate, and chloride ions, and then start to drag the tank;

g. Install carbon core filter potion in the filter barrel to remove organic pollutants;

h. The current density is 5ASF and the cylinder is dragged for 2 hours;

i. The current density is 10ASF and the cylinder is dragged for 2 hours;

j. After the cylinder is dragged, use the Hull cell sheet to confirm the contamination of the tank liquid;

The k.Hull cell sheet was electrolyzed with a current of 2 amps for 5 minutes, and the sheet was not brightened. If it is bright, it is necessary to continue electrolysis and carbon filter filtration.

2. Copper ball treatment

a. 4% V/V AR grade sulfuric acid and 2.5% V/V hydrogen peroxide soak the copper ball for 1.5 hours;

b. Drain off the acid solution, rinse with DI water and use it.

3. Add hole metallization composition and drag cylinder

a. Add the corresponding amount of the pore metallization composition of each component in turn;

b. DC drag cylinder steps:

5ASF drag for 2 hours;

10ASF drag for 2 hours;

15ASF drag for 2 hours;

20ASF dragging for 2 hours, after the DC dragging cylinder is completed, the pulse dragging cylinder is carried out

c. Pulse drag cylinder steps:

(1) Drag cylinder parameter one

Forward current density: 20ASF;

Reverse current density: 52ASF;

Positive and negative time ratio: 20ms: 1ms;

Cylinder drag time: 2 hours

(2) Drag cylinder parameter 2

Forward current density: 25ASF;

Reverse current density: 65ASF;

Positive and negative time ratio: 20ms: 1ms;

Cylinder drag time: continuous drag cylinder to 12AH/L;

After the towing cylinder is completed, test production can be carried out.

The plating conditions are as follows:

Working temperature: 25℃; forward current density 5~40ASF, reverse current density 10~120ASF, forward current time 10~200ms, reverse current time 0.5~30ms, anode is phosphor copper ball or phosphorous containing 99.9% copper Copper corner (containing 0.03-0.06wt% phosphorus). The area ratio of cathode and anode is 1:2; the stirring method is air stirring (low-pressure oil-free blower must be used and passed through the oil-water separation device and filtering device) and cathode moving stirring; the filtering method is continuous filtration with 5-10 μm cotton core.

In this example, the forward pulse current density is different. The experimental design forward pulse current is: 8ASF, 10ASF, 12ASF, 15ASF, the forward and reverse pulse current ratio is 1:2, the forward pulse time is 100ms, the forward/reverse The pulse time ratio is 100:5, and the electroplating time is 120-225min. The specific experimental conditions are as follows:

Bath maintenance during electroplating:

1. The plating solution lost due to evaporation can be supplemented with deionized water;

2. Regularly analyze copper sulfate content, sulfuric acid content and chloride content;

3. Adjust the additives according to the Hull cell test;

4. In normal production, 0.8g of brightener should be added for every 1000AH of operation.

The printed circuit board conditions are as follows:

Board item scope plate material FR4-S1000 plate thickness 4～10mm Minimum aperture 0.35～0.45mm Aspect ratio 12～15

Example 2

Embodiment 2 of the present invention provides a pore metallization composition, which includes copper ions, inorganic acids, polymers polymerized from epoxides and/or alcohols, leveling agents, and brightening agents.

The copper ion source is copper sulfate pentahydrate; the inorganic acid is sulfuric acid and hydrochloric acid, and the polymer formed by the polymerization of epoxides and/or alcohols is an ethylene oxide-propylene oxide copolymer. From Sanyo Chemical, the brand is 50HB; the leveling agent is aminopyrrole-ethylene oxide copolymer, purchased from Shenzhen Aoxinyuan, the brand is VMF; the brightener is bissulfopropyl disulfide and its Sodium salt, purchased from Jiangsu Mengde.

The concentration composition of the porous metal composition is as follows:

component content copper sulfate pentahydrate 40000ppm sulfuric acid 260000ppm hydrochloric acid 60ppm Ethylene oxide-propylene oxide copolymer 1000ppm Aminopyrrole-ethylene oxide copolymer 20ppm Bissulfopropyl disulfide and its sodium salt 1ppm

The specific implementation of the hole metallization method is the same as that of Example 1, except that the specific operating parameters of the reverse pulse method are as follows:

Example 3

Embodiment 3 of the present invention provides a pore metallization composition, the specific implementation of which is the same as that of embodiment 2-3, except that the polymer formed by polymerization of epoxides and/or alcohols is Butanol-ethylene oxide-propylene oxide copolymer with a weight average molecular weight of 200 was purchased from BASF.

Example 4

Embodiment 4 of the present invention provides a pore metallization composition, the specific implementation of which is the same as that of Embodiments 2-3, except that the polymer obtained by polymerizing epoxides and/or alcohols is Butanol-ethylene oxide-propylene oxide copolymer with a weight average molecular weight of 500 was purchased from Sanyo Chemical.

Example 5

Embodiment 5 of the present invention provides a pore metallization composition, the specific implementation of which is the same as that of Embodiments 2-3, except that the polymer obtained by polymerizing epoxides and/or alcohols is Butanol-ethylene oxide-propylene oxide copolymer, with a weight average molecular weight of 100,000, was purchased from Gutian Chemical.

Example 6

Embodiment 6 of the present invention provides a pore metallization composition, the specific implementation of which is the same as that of Embodiments 2-3, except that the polymer obtained by polymerizing epoxides and/or alcohols is Butanol-ethylene oxide-propylene oxide copolymer, with a weight average molecular weight of 10,000, was purchased from Gutian Chemical.

Example 7

Example 7 of the present invention provides a pore metallization composition, the specific implementation of which is the same as that of Examples 2-3, except that the brightener is N,N-dimethyldithiocarboxamide propane Sodium sulfonate.

The specific implementation of the hole metallization method is the same as that of Example 2-3.

Example 8

Example 8 of the present invention provides a pore metallization composition, the specific implementation of which is the same as that of Examples 2-3, except that the leveling agent is sodium thiazolinyl dithiopropane sulfonate, which is purchased from From Wuhan Yalong New Materials Co., Ltd., the grade is SH110.

The specific implementation of the hole metallization method is the same as that of Example 2-3.

Example 9

Example 9 of the present invention provides a pore metallization composition, the specific implementation of which is the same as that of Examples 2-3, except that the leveling agent is 2-imidazolidinylthione.

The specific implementation of the hole metallization method is the same as that of Example 2-3.

performance evaluation

Figure 1 is a schematic cross-sectional view of a printed circuit board through hole, wherein A1, A2, A3, and A4 represent the plating thickness of the surface copper of the printed circuit board through hole cross-section, and B1, B2, B3, and B4 represent the printed circuit board through hole. The electroplating thickness of the hole copper in the cross-section, C1, C2 represent the thickness of the electroplating copper in the middle of the hole of the through-hole cross-section of the printed circuit board.

1. Average Throwing Power TP _Avg

Average Throwing Power = [(B1+B2+B3+B4+C1+C2)/6]*100%/[(A1+A2+A3+A4)/4]

2. Minimum plating capacity TP _min

Minimum Throwing Capacity = [(C1+C2)/2]*100%/[(A1+A2+A3+A4)/4]

Table 1

Example Average Throwing Power (%) Minimum Throwing Power (%) Example 1-1 104.88 101.63 Example 1-2 102.32 109.05 Examples 1-3 88.03 78.32 Examples 1-4 90.43 81.64 Example 2-1 82.08 73.53 Example 2-2 107.95 92.89 Example 2-3 115.82 110.68 Example 2-4 85.38 76.71 Example 3 92.11 88.34 Example 4 97.46 91.11 Example 5 88.32 78.43 Example 6 102.22 98.01 Example 7 107.2 100.15 Example 8 85.31 76.93 Example 9 75.32 64.87

The foregoing examples are illustrative only and serve to explain some of the features of the methods described herein. The appended claims are intended to claim the broadest conceivable scope and the embodiments presented herein are merely illustrative of selected implementations according to a combination of all possible embodiments. Accordingly, it is the applicant's intention that the appended claims not be limited by the selection of examples that characterize the invention. Some of the numerical ranges used in the claims also include sub-ranges within them, and variations within these ranges should also be construed, where possible, to be covered by the appended claims.

Claims (10)

1. A pore metallization composition, characterized in that it comprises 30,000-350,000 ppm of copper ions, 5,000-350,000 ppm of inorganic acids, and 1-10,000 ppm of polymers polymerized from epoxides and/or alcohols. 2 . The pore metallization composition according to claim 1 , wherein the polymer formed by the polymerization of epoxides and/or alcohols comprises polypropylene glycol, polyethylene glycol, ethylene oxide-cyclic At least one of oxypropylene copolymer and butanol-ethylene oxide-propylene oxide copolymer. 3 . The pore metallization composition according to claim 2 , wherein the weight average molecular weight of the butanol-ethylene oxide-propylene oxide copolymer is 100-100,000. 4 . 4 . The pore metallization composition according to claim 3 , wherein the weight average molecular weight of the butanol-ethylene oxide-propylene oxide copolymer is 500-10,000. 5 . 5 . The hole metallization composition according to claim 1 , wherein the hole metallization composition further comprises 0.001ppm-1000ppm of brightener; the brightener comprises N,N-dimethyl-disulfide group 5 . Carbamate-(3-sulfopropyl) ester, 3-mercapto-propylsulfonic acid-(3-sulfopropyl) ester, 3-mercapto-propylsulfonic acid and its corresponding salt, dithiocarbonate-O -Ethyl-S-ester, 3-mercapto-1-propane sulfonate, bissulfopropyl disulfide and its corresponding salt, 3-(benzothiazolyl-S-thio)propyl sulfonate , pyridinium propyl sulfobetaine, 1-sodium-3-mercaptopropane-1-sulfonate, N,N-dimethyl-dithiocarbamate-(3-sulfoethyl) ester, N, Sodium N-dimethyldithiocarboxamide propane sulfonate, 3-mercapto-ethylpropyl sulfonate-(3-sulfoethyl) ester, 3-mercapto-ethyl sulfonate, carbonic acid-disulfide -O-ethyl ester-S-ester, 3-mercapto-1-ethanesulfonate, bissulfoethyl disulfide and its corresponding salt, 3-(benzothiazolyl-S-thio)ethyl At least one of sulfonate, pyridinium ethyl sulfobetaine, and 1-sodium-3-mercaptoethane-1-sulfonate. 6. The hole metallization composition according to any one of claims 1 to 5, characterized in that, the hole metallization composition further comprises 1-5000 ppm leveling agent; the leveling agent is a heterocyclic compound and/or or ethylene oxide copolymer; the ethylene oxide copolymer is a polymer of a heterocyclic compound and ethylene oxide; the heterocyclic compound has the following structure:

The Xe and Rn may be the same or different, and are respectively selected from hydrogen, C ₁ -C ₁₀ alkyl, alkoxy, cyano, hydroxyl, amino, carboxyl, mercapto, sulfonic acid, nitro, amido, alkene One or more of alkynyl, alkynyl and azo; the R ₁ and R ₂ may be the same or different, and are respectively selected from hydrogen, substituted or unsubstituted C ₁ -C ₁₂ alkyl, substituted or unsubstituted One of C ₂ -C ₁₂ alkenyl, substituted or unsubstituted aryl, cyano, hydroxyl, amino, carboxyl, mercapto, sulfonic acid, nitro, amido, alkenyl, alkynyl, azo or more; the B and Y may be the same or different, and are selected from any of C, N, P, O, and S, respectively. 7 . The pore metallization composition according to claim 6 , wherein the substituted aryl group is a C ₁ -C ₄ alkyl and/or hydroxy substituted aryl group. 8 . 8 . The pore metallization composition according to claim 7 , wherein the aryl group is selected from any one of phenyl, xylyl, and naphthyl. 9 . 9. A hole metallization method, characterized in that it comprises: placing a hole metallization composition on a printed circuit board having a plurality of through holes at 25-60° C., using a reverse pulse method to perform copper plating, and electroplating The time is 120-225 min; the hole metallization composition is the hole metal composition of any one of claims 1-8. 10 . The hole metallization method according to claim 9 , wherein the forward and reverse current density ratio of the reverse pulse method is 1:(1.5˜3.5). 11 .

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