Introduction

A PCB, or printed circuit board, is also referred to as a printed wiring board. It is commonly abbreviated as PCB (printed circuit board) or PWB (printed wiring board). Made from an insulating substrate cut to a specific size, it carries at least one conductive pattern and features various types of holes—such as component holes, mounting holes, and plated‑through holes—serving as a replacement for traditional chassis used to mount electronic components and enabling interconnections among them. Because this type of board is manufactured using electronic printing techniques, it is called a “printed circuit board.” The conventional term “printed wiring board” is imprecise, as the board does not actually “print” components; it merely provides wiring traces.

Basic components

Currently, the circuit board is primarily composed of the following:

1. Traces and Pads (Pattern): Traces serve as conductive pathways between components, and the design typically includes large copper pours for ground and power planes. Traces and pads are created simultaneously.

2. Dielectric layer: Used to maintain electrical insulation between conductive traces and between layers; also referred to as the substrate.

3. Vias (Through holes / vias): Through-holes enable electrical connections between layers, while larger through-holes are used for component insertion. Additionally, non-plated-through holes (nPTH) are typically employed for surface-mount alignment and as mounting screw locations during assembly.

4. Solder Resist/Solder Mask: Not all copper surfaces need to be tinned for component mounting; therefore, areas that are not to be tinned are coated with a layer of material—typically epoxy resin—that prevents solder from adhering and avoids short circuits between non‑tinned traces. Depending on the manufacturing process, these coatings are classified as green solder mask, red solder mask, or blue solder mask.

5. Silkscreen (Legend/Marking/Silk screen): This is an optional feature, primarily used to label the names and position frames of components on the circuit board, facilitating post‑assembly maintenance and component identification.

6. Surface Finish: In typical environmental conditions, copper surfaces readily oxidize, resulting in poor solderability. To address this, protective coatings are applied to the copper areas that require soldering. Common surface‑finishing methods include hot‑air solder leveling (HASL), electroless nickel–immersion gold (ENIG), immersion silver, immersion tin, and organic solderability preservative (OSP). Each method has its own advantages and disadvantages, and collectively they are referred to as surface finishes.

Market Status

Over the past decade or so, China’s printed circuit board (PCB) manufacturing industry has grown rapidly, with both its total output value and total production volume ranking first worldwide. As electronic products evolve at an unprecedented pace and price competition reshapes supply-chain dynamics, China—boasting favorable industrial clustering, cost advantages, and a robust market—has emerged as the world’s most important PCB production hub.

Printed circuit boards have evolved from single-layer designs to double-sided, multilayer, and flexible substrates, continuously advancing toward higher precision, greater density, and enhanced reliability. By steadily reducing size, lowering costs, and improving performance, printed circuit boards will continue to maintain robust vitality in the ongoing development of future electronic products.

The future trends in printed circuit board manufacturing technology are moving toward higher density, greater precision, smaller via diameters, finer traces, tighter pitch, enhanced reliability, multilayer construction, high-speed signal transmission, reduced weight, and thinner profiles.

According to the survey data presented in the “China Printed Circuit Board Manufacturing Industry: Market Outlook and Investment Strategy Planning Analysis Report,” in 2010, China had a total of 908 PCB manufacturers above designated size, with combined total assets of RMB 216.176 billion. These companies generated sales revenue of RMB 225.796 billion, up 29.16% year on year, and reported total profits of RMB 9.403 billion, an increase of 50.08% compared with the previous year.