High TG PCB
1. HIGH Tg PCB Material
The glass transition temperature (Tg) is one of the most important properties of any epoxy resin. It is the temperature range at which the polymer changes from hard glass-like material to a soft rubber-like material. In the process of processing, it is not possible to approach this temperature, otherwise, it will cause abnormalities.
2. Tg Control
The circuit board material must be flame retardant, cannot burn at a certain temperature, can only be softened. This temperature point is called the glass transition temperature (Tg). This is the main indicator of material performance parameters. For high-demand PCBs, controlling this parameter is the key point.
The higher the Tg point, the higher the temperature requirement during lamination. And the board will be hard and brittle, which will affect the hole and electrical properties. It is also the core point of our process control.
Ordinary PCB materials will not only soften, deform, melt, and other phenomena at this high TG temperature, but also their mechanical and electrical properties will drop sharply. Leading to the failure of the PCB fee.
3. Tg Classification
Generally, fr4 Tg is 130-140 degrees Celsius, medium Tg is greater than 150-160 degrees Celsius, and high Tg is greater than 170 degrees.
The higher the Tg, the better the heat resistance, moisture resistance, chemical resistance, stability, and other characteristics of the PCB.
FR4 is the code name of epoxy glass material grade.
When the working temperature reaches the melting point (that is, the temperature exceeds the Tg value), the state of the PCB material will change from glass to liquid, which will affect the function of the PCB. This value is related to the stability of PCB dimensions. It is also what customers should pay attention to when designing high TGPCB boards.
Usually, it is made of PCB material with Tg≥170℃, which is called a high Tg printed circuit board. With the rapid development of the electronics industry, high Tg materials are widely used in computers, communication equipment, precision instruments, etc. The design industry is mainly for applications with high requirements and high-quality PCBs.
4 High Tg PCB Material Characteristics
High Tg PCB Evaluation
High Tg PCB Material S1000
- Higher heat resistance;
- Lower Z-axis CTE;
- Excellent thermal stress resistance;
- High thermal shock resistance;
- Excellent PTH reliability.
- Some popular High Tg materials:
- S1000-2 & S1170: Shengyi materials;
- IT-180A: ITEQ material;
- TU768: TUC material.