PCB Process Overview

PCB Process Overview

01. Desmear Chemical

Desmear is a chemical that removes the residue of resin melted by friction heat in hole and the smear (residue) generated by high speed rotation of copper chip and drill bit during mechanical drilling for hole processing. At the same time, when electroless copper plating is performed, it forms an ideal texture on the resin surface to improve the adhesion of the inner wall of the hole.

1. Sweller
• ORChem Chemical name : ORC-310A(Vertical), 315A(Vertical), 315H(Horizontal)
• Penetration of the solvent into the resin → weakening of the intermolecular bonding force (swelling)
• Etching easily

2. Etching
• ORChem Chemical name : ORC-340B
• Etching resin residue changed from polymer to single molecule form
• Reaction (oxidation) of the carbon chain, which is the main component of polymer in resin, with permanganic acid

3. Neutralizer
• ORChem Chemical name : ORC-370(Normal), 372(Etching type), 372NH(None-etching type)
• After permanganic acid treatment, reduce residual insoluble permanganate and manganese dioxide
• Change to soluble manganese and remove
• Give conditioning function

02. Electroless Copper Plating Process

Electroless chemical plating process is the key technology of copper plating to make electrically non-conductive part between layer and layer to be electrically energized when manufacturing double-layer or multi-layer substrate. In order to plating nonconductive parts that do not pass electricity, we have secured chemical reliability such as chemical stability and plating adhesion as a plating technology using chemical oxidation-reduction reaction of chemicals.
Our core chemicals for electroless chemical copper plating have entered the market with proven competitiveness by competing with overseas competitors' chemicals, which have dominated the domestic PCB fine chemical material market for a long time. Currently, we have secured a 30% share of the horizontal type electroless chemical copper plating line in Korea. The core chemicals of our electroless chemical copper plating process are divided into ion type (Ion type) and colloid type (colloid type) according to the palladium type of catalyst used.
Ion type has the advantage that the catalyst itself exists as ion (Ion) and the substrate covering is improved even on the inner wall of the hole with smaller particle size than the colloid catalyst. It is mainly applied to high-density PCB, such as RF-PCB, which has recently become highly integrated, and has recently been used increasingly.
The colloid type is a kind of mixture, and the colloid catalyst acts as a catalyst of the plating reaction by adsorbing the Pd / Sn colloid onto the Conditioning Agent on the inner wall of the PCB original plate hole. The electroless chemical copper process consists of 6 steps, which are divided into preprocessing and chemical copper processing.


1. Cleaner & Conditioner

• The pretreatment process is a Cleaner & Conditioner (C & C) step that removes foreign matter from the nonconductive part of the inner wall of the hole to be plated and provides a conditioning agent so that palladium can be adsorbed well in the subsequent palladium (Pd) catalyst step.


2. Soft Etching

• This is a soft etching step to increase the surface area to increase the adhesion with the electrolytic copper plating process.


3. Pre-dip

• This is a pre-dip step, which is a process to prevent the contamination of catalyst chemicals, which plays an auxiliary role to allow the palladium catalyst to be adsorbed well on the inner wall of the hole.


4. Activator or Catalyst

• A catalyst step for adsorbing palladium on the inner wall of the hole.


5. Reducer / Accelerator

• An Reducer / Accelerator step that removes substances other than Pd from the adsorbed Pd complex or Pd colloid to facilitate bonding with copper when copper plating.


6. 화학동도금 (Electroless Cu Plating)

• Finally, it is a chemical copper plating step that enables copper plating by chemical through oxidation-reduction reaction on palladium on the non-conductive part of the inner wall of the hole.


03. Oxide Process Solution

Interlayer adhesion is a very important factor in the reliability of a product in the manufacture of multilayer circuit boards (MLBs) and highly integrated PCBs. In order to ensure adhesion, and also to withstand thermal shock and physical impact, the process of forcing copper Cu on the inner layer substrate with a circuit to form roughness of Cu is called oxide process.


The oxide process is divided into the Black Oxide Process and the Brown Oxide Process depending on the characteristics of the treatment chemicals. Black Oxide is mainly used for hole processing in LDD (Laser Direct Drill) process. Brown Oxide is used for LDD (Laser Direct Drill) process and lamination process.

We have both types of oxide process chemicals. The Black Oxide process is being supplied to Samsung Electro-Mechanics and others. The Brown Oxide process is being supplied to Korean companies such as Korea Circuit and Daeduck Group as well as domestic and overseas PCB manufactures. In addition, our brown oxide precision chemicals have a high market share in the domestic oxide market, and are expected to continue to grow in the future.


04. DES Process Solution

The DES process consists of three processes: 1. Developing - 2. Etching - 3. Stripping. The PCB process can be implemented through the DES process. In order to realize the circuit after dry film Lamination on the original plate, UV film is applied, and the dry film which is not cured by UV is removed through the developer in the developing process.
In addition to developing solutions for existing circuit formation methods, we also have pharmaceutical materials that can be applied to the SAP / MSAP (Modified Semi-Additive Process) process for manufacturing semiconductor packages.
The etching process is a precise chemical that implements the circuit by carving out the exposed copper part after development. Acid type and Alkali type chemicals are used according to product specifications and customers' requirements for the implementation of defect-free circuits such as undercuts. We have both Acid type and Alkali type chemicals and can cope with various process environments.
The etching process is a surface etching solution for circuit formation, which is divided into Acid type and Alkali type. Acid type is applied to panel plating method. In order to protect the circuit formation part on the substrate surface to form a circuit after electroplating, dry film is exposed to ultraviolet ray to peel off the surface except the part where circuit is formed, This is a chemical that only corrodes the surface except for the peeling circuit formation.


Alkali type is applied to pattern plating method. It is coated with dry film during plating, curing only the parts other than the circuit by ultraviolet rays, protecting the circuit by solder (tin + lead) plating, Solder (tin + lead) This is a chemical that removes copper (copper) and other residues without affecting the plated circuit.
D/F stripping agent is used in the stage of circuit formation in PCB manufacturing. It can be used for various kinds and specifications of dry film, line equipment using stripper, and dry film size and stripping time after stripping, Because we are using it to adjust, we provide customized drugs to meet the requirements of each manufacturer. In particular, we have developed a stripper that is compatible with the conventional PCB manufacturing process (Substrate method), as well as a dedicated stripper that is suitable for the latest PCB manufacturing methods such as SAP (Semi Additive Process) and MSAP (Modified Semi-Additive Process) We have completed mass production application tests and are preparing for mass production. Our MSAP-specific drugs, which meet various conditions and specifications, are expected to contribute greatly to future sales growth.

05. Micro Etchant Chemical

Pretreatment Etching chemicals are used in almost all processes of PCB manufacturing and are used as pretreatment chemicals. Especially, it plays a role of removal of oxide film on the surface, removal of contaminants and impurities, formation of surface roughness and dry film (D / F) Lamination, Chemical copper plating, finishing process (Tin plating, nickel plating, gold plating, etc.) and is also used for the purpose of increasing adhesion. We are divided into sulfuric acid / hydrogen peroxide type, persulfate type, nitric acid type and organic acid type chemical according to the base chemicals which are put in accordance with the PCB manufacturing process environment. We have all four kinds of chemicals. Sulfuric acid / hydrogen peroxide type chemicals are easy to control the etching amount and low running-cost, and they are used for various applications in the market. Especially Sodium Persulfate (SPS) type chemicals are mainly used for plating pretreatment. Nitric acid type chemicals are used for D / F (Dry Film) and PSR (Photo Solder Resist) pretreatment, which require high adhesion. Organic acid type chemicals are widely used for processes requiring high adhesion and reliability.

06. Electric copper plating process chemicals

Electric copper plating process chemicals are used to improve the uniform plating thickness and leveling property in the hole through the electroplating of the substrate after the chemical copper plating process. Brightener, Carrier, Leveler It is composed of three kinds of organic additive and chlorine ion. It improves the electrodeposition thickness of copper and gives a smooth and elastic plating layer.

07. Others

The ENIG process is one of the final surface treatment processes of the circuit. In order to prevent oxidation of the processed substrates and parts, the surface is protected by gold plating after nickel plating. We have all the chemicals of ENIG process (degreasing, etching, catalyst, electroless nickel plating, electroless gold plating) and have various advantages such as minimized discoloration and excellent price competitiveness.

The EMI shielding process is a process for absorbing or reflecting electric and magnetic wavelengths such as electric and magnetic fields generated by electric or electronic products, and preventing electromagnetic waves from transferring to the inside. It is a precision chemical material that shields electromagnetic waves by using it as a shielding paint when coating the product rather than giving it.
Currently, nanotechnology used for shielding electromagnetic waves includes coatings, functional polymers, and metal materials. Our EMI shielding chemicals are used as catalysts and electroless plating chemicals. In order to shield electromagnetic waves, colloidal palladium catalyst is treated on the fibers and plating is carried out by electroless plating. Electroless plating chemicals can control the plating thickness of the fiber by adjusting the concentration, which can increase the shielding effect. In addition, nickel (Ni) plating and copper (Cu) plating can be alternately performed to double the shielding effect. It is more likely to expand the market in the future as it has more competitiveness in selling unit price and technical service than multinational imported brand. In addition, we are protecting the technology through patents related to textile plating.

[Equipment cleaning]
Equipment cleaning agent is used to clean equipment such as D/F (Dry Film) and PSR (Photo Solder Resist) phenomenon and peeling step, and it has a dedicated equipment cleaning agent according to characteristics of D/F and PSR.

[Rack Stripper]
Rack peeling agent is a chemical agent for copper (Cu) removal such as stainless steel mechanism that fixes a substrate in the course of electric copper plating, and has excellent chemical stability and high-speed etching rate. Currently, it is mainly used in large enterprises for removing equipment in the PCB manufacturing process.