PCB Fabrication Methods

In terms of manufacturing methods, PCBs are manufactured in the following ways:

Subtractive Method: The circuit pattern is formed by chemically or physically removing the unwanted copper layer from the substrate.

Additive Method: The desired circuit pattern is formed by depositing conductive material directly on the substrate.

Semi-additive Method:  Combining the characteristics of subtractive and additive methods, a special process is used to form the circuit pattern on the substrate.

The subtractive method is a method of making PCBs, and its core idea is to chemically or physically remove the unwanted copper layer from the substrate to form the circuit pattern.

The Advantages of The Subtractive Method Mainly Include:

The ability to directly produce copper-free holes that fall on large copper skins (without the need for a second drill) and larger copper-free holes.

The ability to produce printed circuit boards with larger copper residual rates on both sides of the outer layer.

The process is relatively short and the cost is relatively low.

Addition method is an insulating substrate surface, selective deposition of conductive metal and the formation of conductive pattern method.

The Advantages of The Addition Method Mainly Include:

As the addition method to avoid a large number of etched copper, and the resulting large number of etching solution treatment costs, greatly reducing the cost of production of printed circuit boards.

Additive process than the process of reducing the process into a process to reduce the process by about 1 / 3, simplifying the production process, improve production efficiency. Especially to avoid the product grade, the higher the process of the more complex vicious circle.

Additive process can achieve flush wires and flush surface, so that the manufacture of SMT, such as high-precision printed circuit boards.

In the addition process, due to the hole wall and wire at the same time chemical plating, hole wall and wire at the same time plating, hole wall and wire at the same time coated with solder resist, so the hole wall and wire at the same time to get protection, thus improving the reliability of the printed circuit board.

Additive method can avoid a large number of etching copper and etching solution processing costs, reduce the cost of production of printed circuit boards, and process simplification, improve production efficiency. The reduction of the law can not achieve flush wire and flush surface, can not manufacture SMT, such as high-precision printed circuit boards.