Skip to content

Ultimate guide to choose PCB material for beginners 2022

What are printed circuit boards made of?What are the basic components?

pcb basic components

A printed circuit board is an important component in electronic systems, whose main function is to mount and solder electronic components on it to create a mechanical shape and electrical connection between components. According to the layers, we can build circuit boards that can be single-sided, double-sided, or multi-layers. The paths in different layers are connected by vias; the multi-layer PCB increases the component density much higher.
Major PCB components include:
1.Capacitor
2.Resistors
3.Transistors
4.Sensor
5.Transformer
6.diodes

How many types of PCB materials are there?

A PCB generally consists of 4 types of materials, heated together into a single layer, in order from top to bottom: Silkscreen, Soldermask, Copper, and Substrate.

•Silkscreen: Printed on the outer layer of the circuit board (usually white), it represents the name or value of the component, making it easy to identify which component it is, how much it is worth… Silkscreen can be printed on both sides of the circuit board. This is also the non-conductive layer in the PCB.

Solder mask: it is the outer glossy coating of the circuit board, usually blue, red, or green. This coating avoids short-circuiting on the board where the circuit lines are too close together and makes soldering components easy. This is the non-conductive layer in the PCB.

•Copper: it is a thin layer of copper pressed onto a substrate with a mixture of heat and an adhesive. This copper coating will have different thicknesses depending on the purpose of use, the commonly used unit is OZ (1OZ = 0.035mm = 35 um).

PCB substrate (substrate – dielectric layer):
It is the main component to distinguishing different types of printed circuit materials, when it comes to PCB material, it must be understood that it is the type of material that constitutes the substrate.
Substrate panels are manufactured by maintaining certain pressure and temperature on layers of fiber or paper together with thermosetting resins to form a fused sheet of uniform thickness. The fiber used, the resin, and the ratio between them determine the type of different substrate sheets such as FR-4, CEM-1, and G-10…and also determine their properties.

Some important properties of the substrate sheet such as fire resistance, dielectric constant (e r ), loss factor (tδ), strength, and Z-axis expansion coefficient (thickness varies with temperature) )…
There are quite a few different dielectrics that can be selected to provide different insulation values depending on the requirements of the circuit.

Some prominent primary materials used in the PCB industry are FR-2 (phenolic cotton paper), FR-3 (cotton and epoxy paper), FR-4 (glass fiber and epoxy), FR-6 (glass fiber and epoxy resin), translucent glass and polyester), CEM-1, CEM-2 (cotton paper and epoxy), CEM-3 (non-adhesive glass and epoxy), CEM-4 (bonded glass and epoxy), CEM-5 (glass and epoxy resin). adhesive crystals and polyester). Thermal expansion is an important consideration, especially for BGA, where fiberglass offers the best dimensional stability.

What is FR4 PCB material?

FR-4: The composition is glass fiber impregnated with epoxy resin. It comes with low water absorption (about 15%), good electrical insulation properties, and good arc resistance. This is a very common PCB material in the industry, often used up to 130°C. The FR-4 is about 0.1mm thin and can be used for boards that need to be bent.

Aluminum: metal circuit board or insulating metal base (IMS) coated with a thin dielectric capable of conducting heat, commonly used for power switches that need cooling, and LED systems. It is usually single-layer, sometimes double-layer boards like the FR-4, laminated onto aluminum metal sheets with common thicknesses of 0.8, 1, 1.5, 2, or 3mm.

Flexible substrates: flexible substrates, which can be independent copper-coated foils or laminated on a thin hardener.

Which metal is most widely used in PCB?

FR-4 is also a widely used and popular material today. FR-4 is still the most widely used PCB material; it offers the right balance between cost, manufacturability, electrical properties, durability, and performance. The choice of printed circuit material depends on the specific application. If customers need to make circuits with special requirements, they can contact us directly.

Some common materials:
FR-2: the composition is phenolic paper or phenolic cotton paper, the paper is impregnated with phenol-formaldehyde resin. It is cheap, and popular in low-end consumer electronics with 1-layer circuit boards. Electrical properties worse than FR-4, poor arc resistance, commonly used up to 105°C. Plastic composition varies by supplier.

What plastic is PCB made of?

Polycarbonate

Polycarbonate is up to thirty times stronger than acrylic and two hundred times stronger than glass. This is the main reason that polycarbonate is widely used in the printed circuit board industry: its resistance. Yes, it is highly resistant to shocks and collisions, as well as very flexible.
These characteristics have made polycarbonate a well-known and widely applied PCB material in the electronic industries.

What etching material is used for PCB?

Why is etching necessary?

In most cases, it is necessary to remove the surface layer of grease or dirt and to reveal the structure of the materials. In the production of printed circuit boards and integrated circuits (by photolithography), tracks and pads are formed in this way. Membranes are also made by etching holes. Sometimes the surface is polished in this way after unsuccessful machining.

Etching and basic chemical methods

Main types:
•Chemical
•Electrochemical
•Ion-plasma

What is the best PCB material?

FR material is the best PCB material with good fire resistance. After being combined with thin copper layers on the surface of the FR layer of fireproof material, people produce the material to meet the printed circuit.
What is FR4 material structure?
1. For a common circuit board, the core can meet the stiffness and make the base for the circuit with the copper layer on it.
2. For 2-layer printed circuit boards, the FR4 type is separated between the top and bottom copper layers, for multi-layer printed circuit boards it is common to add FR4 PrePreg layers between the inner and outer copper layers.
3. The inner core of the FR4 material, in addition to the task of making a rigid object and a foundation for the circuit, also has another task to help prevent the two layers of copper, to help create an insulating dielectric layer.
4. For creating a required thickness of the PCB is done by adding or removing laminates so that different thicknesses can be made.

PCB material selection for high speed design

PCB Material Selection Guide

With the development of electronic technology, there is a great demand for high-speed PCB design to operate. They can work with integrated circuits at high speed for most electronic devices, even fairly simple ones.
When you design a high-speed PCB, it needs to consider several factors and parameters including the best material for high-speed design. Before choosing high-speed design material you need to look into the following factors:
PCB Thermal Conductivity
•Thermal Expansion
•Glass Transition temperature
•Dispersion
The best PCB material for high-speed design is grade FR4 nonconductive material that comes with epoxy laminate qualities. It performs best against high temperature and humidity environmental variations.

How do I choose a PCB material?

You need to choose pcb material according to your requirement for instance what kind of chemical and thermal properties you are looking for or your future project.
One of the important factors in choosing pcb materials is the type of pcb board you are making: for example single-sided pcb, flex, rigid-flex, or HDI PCB.

Share:

Facebook
Twitter
Pinterest
LinkedIn

Product Categories

Most Popular

Contact Us

IBE News

Related Posts

Industries

INDUSTRIES WE SERVE Click on each industry to learn more about how we make custom printed circuit board solutions for each market.Our industries served include

Read More »