Amber PCB Blog

Plating process is currently widely used in various areas of national product, only serious action to effectively conserve energy, protect the environment. In the following a brief introduction on some basic knowledge of plating. Plating Category: Acid Bright Copper

Electroplating electroplating nickel / gold plating tin.

Process: the entire board pickling copper plating → → → micro etching acid degreasing pickling → → → pickling → Graphics tinned copper plating nickel → → → citric acid leaching gold.

Process description.

(1) pickling.

① role and purpose: to remove board oxide, activated plate surface, the general concentration of 5% to 10%, mainly to prevent water into the instability caused by sulfuric acid bath.

② using CP grade sulfuric acid, acid leaching time not too long, to prevent oxidation of board; in use for some time, the acid appears cloudy or when the timely replacement of copper content is too high to prevent the pollution of surface plating Tonggang and board.

(2) copper plating the entire board.

① role and purpose: to protect just the chemical deposition of thin copper, to prevent being etched away, by electroplating, after its increase to a certain extent.

② the entire board process parameters related to copper plating: Bath The main components are copper sulfate and sulfuric acid, high acid, low copper formula, to ensure that when the board plating thickness uniformity of the deep hole and covering power; acid content of more than 180 to 240 g / l; copper sulfate with

Generally the amount of 75 g / l or so, the bath may have trace amounts of chloride ions, and copper as a secondary gloss, glossy photo together the effects of agents; light of the Addition of copper content in the 3 ~ 5ml / L, copper light of the Addition An hour by thousands of the general method or based on actual production

Board effect to supplement; the entire board plating current of typically 2 Security / square decimetre plating area can be calculated by multiplying the board; Tonggang temperature control in 22 to 32 degrees.

③ process maintenance: An hour a day according to time to add thousands of copper-ray dose; check the filter pump is working properly; every 2-3 hours application of clean, wet rag and clean the cathode conductive rod; a week on a regular basis and through the Hall of Seoul to adjust the optical cell test

Agent content replenish; a week to clean the anode conductive rod, electrical connectors at both ends of the trough replenish copper ball titanium anode basket; monthly titanium anode baskets should be checked for damage and the timely replacement of bags; and check the anode titanium whether the accumulation of a basket at the bottom of anode mud; every half

Around specific decisions based on the need for pollution bath big deal; every two weeks to replace the filter pump filters.

④ anode containing a small amount of phosphorus copper ball, the purpose is to reduce the anodic dissolution efficiency and reduce copper production.

⑤ When additional drugs, such as the addition of relatively large number of copper sulfate or sulfuric acid should be supplemented several times slowly; otherwise it will create the bath temperature is too high, accelerated decomposition of light pollution bath.

(3) acidic degreasing.

① purpose and function: to remove the surface oxide copper lines, and graphics to ensure a copper or nickel plated copper binding force between.

② use of acid addition to oil, oil production only control the concentration and time than you can.

(4) micro-pitting.

① purpose and function: clean copper surface roughening line, to ensure a copper pattern plating of copper and the binding force between.

② micro-corrosion agent used over sodium sulfate.

(5) pickling.

① role and purpose: to remove board oxide, to prevent water into the instability caused by sulfuric acid bath.

② sulfuric acid leaching using the CP-level, time not too long, to prevent oxidation.

(6) Graphics copper plating, also known as secondary copper.

Purpose and role: To meet the line rated current load, the copper lines and holes need to reach a certain thickness, the line is to hole copper and copper lines thickened to a certain thickness of copper.

(7) tin plating.

① purpose and function: the purpose of graphics is to use pure tin plating of pure tin as a metal resist layer simply to protect the etched lines.

② mainly by sulfuric acid tin bath, sulfuric acid and additives; stannous sulfate content control at 35 g / liter or so, about 10% sulfuric acid control; tin additives, generally in accordance with the addition of thousands of hours of ways to add security or to the actual production board effect; tin plating current calculation generally based on 1.5 amp / square decimetre plating area can be multiplied by the board; tin cylinder temperature was maintained at room temperature, the general control of 22 to 30 degrees, so the temperature is too high in the summer can be added cooling temperature control system installed.

③ process maintenance: An hour a day according to time to add thousands of tin additive agent; check the filter pump is working properly; every 2 to 3 hours the application of clean wet rag and clean the cathode conductive rod; analysis of a week on a regular basis and through Hull Cell test to adjust the content of tin additives; a week to clean the anode conductive rod, electrical connectors at both ends of the trough; monthly check whether the damaged anode bag and promptly replaced; and check bags at the bottom of the anode anode mud; every two weeks to Replace the filter pump filter.

④ When the process above to add drugs, not repeat.

(8), nickel plated.

① purpose and function: primarily as a nickel-plated copper layer and barrier layer between the gold layer to prevent the Bronze mutual penetration, solderability of the board and service life; while the nickel layer also greatly increased the gold backing layer mechanical strength.

② the entire board copper plating process parameters related to: the addition of nickel additive in accordance with the general approach to the thousands of hours of additional safety or effectiveness based on the actual production of plate, add the amount of approximately 200ml/KAH; graphics nickel plating current calculation generally based on two security / cm ^ m can be multiplied by the plating area of ​​the board; nickel-cylinder temperature is maintained at 40 to 55 degrees.

③ process maintenance: An hour a day according to time to add thousands of nickel plating additives; check the filter pump is working properly; every 2 to 3 hours the application of clean wet rag and clean the cathode conductive rod; a week on a regular basis and through the Hall of Seoul Cell test to adjust the content of nickel replenish additives; a week to clean the anode conductive rod, electrical connectors at both ends of the trough replenish nickel-titanium anode basket in the corner, with a low current electrolysis 6 to 8 hours; should be checked monthly titanium anode basket, and timely replacement bags for damage; and check whether the bottom of the anode titanium basket piled with anode mud; replace the filter every two weeks drug pump filter.

⑤ When the process above to add drugs, not repeat.

(9) plating: gold and water into a hard gold plating process, basically the same bath composition, hard gold tank some more trace metals nickel, cobalt, iron and other elements.

① purpose and function: Gold is a precious metal, with the weldability, oxidation resistance, corrosion resistance, contact resistance, good wear resistance characteristics of alloy.

② At present the main circuit board for the citric acid gold plating bath tank, maintenance is simple, easy to operate.

③ water Jinjin content control in 1 g / l or so, pH value 4.5, temperature 35 ° or so.

④ major drugs have acid added to adjust salt, basic adjustment of salt, conductive salt, gold and gold salts and other additives added.

⑤ gold plate electroplating recovery after the application of pure water washing, as washing, but also can be used to complement changes in evaporation of liquid gold cylinder.

⑥ platinum gold cylinder should be made titanium mesh anode.

⑦ gold cylinder core organic contamination of carbon continuous filtration, and added amount of gold plating additives.