The classification of the electroplating process:

Acid bright copper plating tin plating nickel/gold plating

Second, the technological process:

Pickled - the full plate electroplating copper - graphic transfer - acidic degreasing - secondary counter-current rinse - micro erosion - 2 - pickled - tin - secondary countercurrent rinsing

Countercurrent rinsing and pickled to graphics electroplating copper, secondary counter-current rinse to nickel plating, the secondary water to soak citric acid, gold plated - recycling - 2-3 water washing and drying

Three, process description:

(a), pickled

Function and objective: (1) to remove surface oxide, activated panel, general concentration in 5%, some remain at around 10%, mainly due to prevent moisture into the slot liquid sulfuric acid content is unstable;

(2) the pickling time shoulds not be too long, to prevent the surface oxidation; In use after a period of time, acid appear cloudy or high copper content should be replaced in a timely manner, to prevent pollution of the copper plating on the surface of the cylinder and plate;

(3) should be used here C.P grade sulfuric acid;

(2), the whole plate electroplating copper, also called a copper, plate, the Panel - plating

Function and objective: (1) protection just chemical copper deposition of thin, prevent chemical copper oxidized by acid etching, after plating to add to a certain extent

(2) the full plate electroplating copper related process parameters: bath main ingredients are copper sulfate and sulfuric acid, high low acid copper formula, guarantee the uniformity of the distribution of the plate thickness of electroplating and deep plating ability of deep Kong Xiaokong; Sulfuric acid content in more than 180 grams/liter, person of 240 g/l; Copper sulfate content is in commonly 75 g/l, the other slot liquid adding trace amounts of chloride ions, as auxiliary luster agent and copper light agent common gloss effect; Copper light agent amount or open cylinder quantity in commonly 3 to 5 ml/L, adding copper light agent generally in accordance with the method of kiloampere hours supplement or plate according to the actual production effect; Full board electroplating current generally calculate according to Ann/square decimeter 2 times the plate can be plating area, for full plate electric to the plate length dm x width dm * 2 * 2 a/DM2; Copper cylinder temperature at room temperature, average temperature is less than 32 degrees, more control in 22 degrees, so in the summer because of the temperature is too high, the copper cylinder suggest that the cooling temperature control system;

(3) process maintenance: according to the daily kiloampere hours to replenish copper light agent, according to the 100-150 ml/KAH supplement add; Check whether the filter pump is working properly, the presence of air leakage phenomenon; Apply every 2 to 3 hours the cathode conductive rod clean wet rag scrub clean; Every week, regular analysis of copper cylinder copper sulfate (1 time/week), sulfuric acid (1 time/week), content of chlorine ions (2 times per week), and to adjust the light through hole groove test agent content, and timely supplement relevant materials; A week to clean anode conductive rod, electrical connectors on both ends of the tub, timely supply titanium anode copper ball in the basket, with low current zero. 2-0. 5 asd electrolytic 6-8 hours; Every month should check whether there is any breakage on anode of titanium basket bag, damaged should be replaced in a timely manner; And check whether the bottom of the titanium anode baskets are stacked with anode slime, if you have should be cleaned in time; Using carbon core filtration 6-8 hours continuously, at the same time, low current electric lift; Every six months or so according to the specific slot liquid pollution condition to decide whether to need to deal with the large (activated carbon powder); Every two weeks to replace filter pump filter;

(4) big handler: a. anode and anode poured out, cleaning the surface of the anode anode membrane, and then put inside packaging barrels of copper anode, with micro inhibitor coarsening copper surface evenly pink can, water rushed after dry, loading titanium basket, side into the acid tank standby b. put titanium anode baskets and anode bag in 10% alkali soak 6 to 8 hours, water ran dry, reoccupy dilute sulphuric acid immersion, 5% reserve water ran dry; C. bath will be transferred to the reserve tank, add 1-3 ml/L 30% hydrogen peroxide, began to heat, stir to stay open air temperature to 65 degrees, heat preservation and air mixing 2-4 hours; D. Turn off the air mixing, activated carbon powder by 3-5 g/l will slowly dissolve into the bath, after being dissolved completely, open air mixing, insulation so 2-4 hours; E. turn off the air mixing, heating, activated carbon powder slowly settle to the bottom of the channel; F. for temperature dropped to 40 degrees, with 10 um PP filter aid powder filtration tank liquid to clean the work groove, open air mixing, into the anode, hang the electrolytic plate, press 0. 2-0. 5 asd electrolytic low density current 6-8 hours, g. the assay analysis, adjustment of sulfuric acid, copper sulfate, chloride ion content to normal operating range; According to the experimental results on hall added light agent; H. after being electrolytic plate panel color evenly, can stop the electrolysis, and then press 1 to 1. 5 asd electrolysis current density of membrane treatment 1 to 2 hours, to be good adhesion anode generated on a layer of uniform density of black phosphate film can; I. try plated OK.;

(5) anode copper ball contains 0. 3-0. 6% of phosphorus, the main purpose is to reduce the anodic dissolution efficiency, reduce the production of copper powder;

Added 6 medicines, such as adding amount is larger, such as copper sulfate, sulfuric acid; After adding should be low current electrolysis; Should pay attention to safety when adding sulfuric acid, adding quantity is big (more than 10 liters) should be slowly adding several times. Otherwise there will be a great bath temperature is too high, light agent decomposition is accelerated, bath pollution;

All landowners adding should pay special attention to the chloride ion, chlorine ion because special low (30-90 parts per million (PPM), to fill overtime must use accurate measuring cylinder or cup weighing rear can add; 1 ml of hydrochloric acid contains about 385 parts per million of chloride ions,

Today drug add calculation formula:

Copper sulfate (unit: kg) = (75 -) X X grough (l) / 1000

Sulfate (unit: L) = (10%) X g/L X grough (L)

Or (unit: L) = g/L (180 - X) X grough (L) / 1840

Hydrochloric acid (unit: ml) = (X) and 60 PPM X grough (l) / 385

(3), acidic degreasing

(1) purpose and function: remove the line on the surface of the copper oxide, ink film residue glue, to ensure a copper and graphics bonding force between the copper and nickel plating

(2) acid used to remember here in addition to the agent, why not use alkaline agent and alkaline agent removal more acidic degreasing effect in addition to the agent has better? Mainly because graphic printing ink is not alkali resistance, can be damaged by graphic lines, so the graphics before plating can only use acid in addition to the agent.

Only when the (3) production control in addition to the oil concentration and time can be, in addition to the oil concentration at about 10%, time guarantee in 6 minutes, a long time will not have a bad effect; Bath use replacement is 15 m2 / l in accordance with the working liquid, added to add according to the 100 - square - meter 0. 5 to 0. L;

(4), micro erosion:

(1) purpose and function: clean the copper surface coarsening lines, to ensure that graphics electroplating copper and the cohesive strength between a copper

(2) inhibitor used more sodium persulfate, uniform stability, coarsening rate is washed, general control concentration of sodium persulfate at around 60 grams/liter, time control in about 20 seconds, add according to the 100 - square - meter 3-4 kilograms of pharmaceuticals, Copper content of control under 20 g/l; Other maintenance in cylinder with heavy copper corrosion.

(5), pickled

1) role and purpose:

To remove surface oxide, activated panel, general concentration in 5%, some remain at around 10%, mainly due to prevent moisture into the slot liquid sulfuric acid content is unstable;

(2) the pickling time shoulds not be too long, to prevent the surface oxidation; In use after a period of time, acid appear cloudy or high copper content should be replaced in a timely manner, to prevent pollution of the copper plating on the surface of the cylinder and plate;

(3) should be used here C.P grade sulfuric acid;

(6), graphics, copper plating, also called secondary copper, copper plating

(1) purpose and function: to satisfy each line rated current load, each line and hole copper copper needs to reach a certain thickness, circuit copper plating in a timely manner will be the purpose of the hole thickness of copper and copper thickening of the line to the certain;

(2) other projects with the full plate electroplating

(7), electroplating tin

(1) purpose and function: graphic purpose of pure tin plating using pure tin as pure metal corrosion resistant layer, protecting circuits etching;

Bath (2) is mainly composed of stannous sulfate, sulfuric acid and additives; Stannous sulfate content control in 35 g/l, sulfuric acid control around 10%; Tin plating additives added generally in accordance with the method of kiloampere hours supplement or plate according to the actual production effect; Electroplating tin the current calculation of general press 1. 5 / square decimeter Ann multiplied by the board to plating area; Tin cylinder temperature at room temperature, average temperature not to exceed 30 degrees, more control in 22 degrees, so in the summer because of the temperature is too high, tin cylinder suggest that the cooling temperature control system;

(3) process maintenance: according to the daily kiloampere hours to replenish tin plating additive agent; Check whether the filter pump is working properly, the presence of air leakage phenomenon; Every 2-3 hours application of the cathode conductive rod clean wet rag scrub clean; Weekly regularly analysis of cylinder stannous sulfate (1 time/week), sulfuric acid (1 time/week), and to adjust the through hole slot test tin plating additive content, and timely supplement relevant materials; A week to clean anode conductive rod, tub electric connection on both ends. With low current 0 per week. 2-0. 5 asd electrolytic 6-8 hours; Every month should check whether there is any damage on the anode bag, damaged should be replaced in a timely manner; Anode bag and check whether the accumulation has anode slime, if any should be cleaned in time; A month with carbon core filtration 6-8 hours continuously, at the same time low current electric lift; Every six months or so according to the specific slot liquid pollution condition to decide whether to need to deal with the large (activated carbon powder); Every two weeks to replace filter pump filter;

Pet-name ruby handler: a. take out anode, remove the anode bag, with copper brush cleaning the surface of the anode, water rushed after dry, into the anode bag, placed in acid tank standby b. anode bag put into 10% alkali soak 6 to 8 hours, water ran dry, reoccupy dilute sulphuric acid immersion, 5% reserve water ran dry; C. bath will be transferred to the reserve tank, press 3-5 g/l will be activated carbon powder slowly dissolved into the bath, after being dissolved completely, adsorption of 4 to 6 when I was a child, with 10 um PP filter aid powder filtration tank slot liquid to clean the work, in the anode, hang the electrolytic plate, press 0. 2-0. 5 asd electrolytic low density current 6-8 hours, d. the assay analysis, adjustment of sulfuric acid, stannous sulfate content to normal operating range; According to the experimental results on hall added tin plating additives; E. after being electrolytic plate board face even color, namely stop electrolysis; F. try plated OK.;

Added (4) drugs, such as adding amount is bigger as stannous sulfate, sulfuric acid, After adding should be low current electrolysis; Should pay attention to safety when adding sulfuric acid, adding quantity is big (more than 10 liters) should be slowly adding several times. Otherwise there will be a great bath temperature is exorbitant, stannous oxide, bath to speed up the aging;

(5) drug add calculation formula:

Stannous sulfate (unit: kg) = (40 - X) X grough (l) / 1000

Sulfate (unit: L) = (10%) X g/L X grough (L)

Or (unit: L) = g/L (180 - X) X grough (L) / 1840

(8), nickel plating,

(1) purpose and function: nickel plating layer is mainly as a barrier layer between copper and gold layer, prevent gold copper diffusion, weldability and service life of the board; Nickel layer render again at the same time also greatly increase the mechanical strength of the gold layer;

(2) the full plate electroplating copper related process parameters: common nickel plating additives added according to the thousands of hours to supplement or according to the actual production plate effect, adding amount of about 200 ml/KAH; Graphics of nickel electroplating current generally calculate according to Ann/square decimeter 2 times the plate can be plating area; Nickel tank temperature at 40-55 degrees, average temperature in 50 degrees or so, so nickel cylinder to add heating, temperature control system;

(3) process maintenance: according to the daily kiloampere hours to replenish nickel plating additives; Check whether the filter pump is working properly, the presence of air leakage phenomenon; Every 2-3 hours application of the cathode conductive rod clean wet rag scrub clean; Every week, regular analysis of copper cylinder nickel sulfate (sulfamic acid nickel) (1 time/week), nickel chloride (1 time/week), content of boric acid (1 time/week), and to adjust the through hole slot test nickel plating additive content, and timely supplement relevant materials; A week to clean anode conductive rod, electrical connectors on both ends of the tub, timely supplementary anode nickel titanium basket of Angle, with a low current zero. 2-0. 5 asd electrolytic 6-8 hours; Every month should check whether there is any breakage on anode of titanium basket bag, damaged should be replaced in a timely manner; And check whether the bottom of the titanium anode baskets are stacked with anode slime, if you have should be cleaned in time; Using carbon core filtration 6-8 hours continuously, at the same time, low current electric lift; Every six months or so according to the specific slot liquid pollution condition to decide whether to need to deal with the large (activated carbon powder); Every two weeks medicine replacement filter pump filter;

4 big handler: a. anode and anode poured out, cleaning the anode, and then put inside packing nickel Angle of barrels, coarsening nickel Angle to the surface with micro etching agent evenly pink can, water rushed after dry, load the titanium basket, side into the acid tank standby b. put titanium anode baskets and anode bag in 10% alkali soak 6 to 8 hours, water ran dry, reoccupy dilute sulphuric acid immersion, 5% reserve water ran dry; C. bath will be transferred to the reserve tank, add 1-3 ml/L 30% hydrogen peroxide, began to heat, stir to stay open air temperature to 65 degrees, heat preservation and air mixing 2-4 hours; D. Turn off the air mixing, activated carbon powder by 3-5 g/l will slowly dissolve into the bath, after being dissolved completely, open air mixing, insulation so 2-4 hours; E. turn off the air mixing, heating, activated carbon powder slowly settle to the bottom of the channel; F. for temperature dropped to 40 degrees, with 10 um PP filter aid powder filtration tank liquid to clean the work groove, open air mixing, into the anode, hang the electrolytic plate, press 0. 2-0. 5 asd electrolytic low density current 6-8 hours, g. the assay analysis, adjustment of nickel sulfate or sulfamic acid nickel, nickel chloride and boric acid content to normal operating range; According to the experimental results on hall complement nickel plating additives; H. after being electrolytic plate panel color evenly, can stop the electrolysis, and then press 1 to 1. Current density of 5 asd 10-20 minutes activate the anode electrolysis treatment; I. try plated OK.;

Added 5) drugs, such as adding amount is larger, such as nickel sulfate or sulfamic acid nickel, nickel chloride, after adding should be low current electrolysis; Should be recharge when adding boric acid boric acid in a clean and nickel anode bag hanging into the cylinder, not directly to join groove;

6 nickel plating suggest add a recovery after washed, open cylinder with pure water, can be used to supplement nickel tank for heating and volatile liquid level, recycling water followed by secondary counter-current rinse;

7 drug add calculation formula:

Nickel sulfate (unit: kg) = (280 -) X X grough (l) / 1000

Nickel chloride (unit: kg) = (45 - X) X grough (l) / 1000

Boric acid (unit: kg) = (45 - X) X grough (l) / 1000

(9), the electric plating: divided into hard gold plating gold (gold) and water (gold) process, the soft gold plated gold and fluid composition, much hard gold slot only some trace metal elements such as nickel or cobalt and iron;

(1) purpose and function: as a kind of precious metals, gold has good weldability, oxidation resistance, corrosion resistance, small contact resistance, alloy excellent wearability and so on;

(2) the current PCB electric plating mainly for citric acid gold bath, with its simple maintenance, operation simple and convenient and widely used;

(3) the water content of gold under 1 g/l, PH 4. Five or so, the temperature 35 degrees, share about 14 baume degree, the current density of 1 asd or so;

(4) main add drugs to adjust PH adjustment of salt and alkali salt, acid type to adjust the proportion of conductive salt and gold-plated additives and gold salts, etc.

Cylinder (5) to protect the gold, gold cylinder should be added before the citric acid leaching tank, which can effectively reduce the pollution and keep the gold for gold cylinder cylinder;

6 gold plate electroplating after application of a pure water wash as recycling water, at the same time can also be used to supplement the golden urn evaporating liquid level change, recycling water followed by secondary flow water wash, gold plate after washed into the 10 grams/liter lye to prevent oxidation gold plate;

7 gold cylinder should adopt platinum plating titanium mesh anode, generally stainless steel 316 is easy to dissolve in nickel chromium iron and other metal contamination gold cylinder, cause gold plated white, plating, defects such as black;

Today gold cylinder organic pollution carbon core continuous filtration, adding suitable amount of gold plating additives.