SMT DIP Bare PCB Electronic Components Assembly Service

 What is high Tg PCB?

The excellent heat dissipation performance of Metal Core PCB (MCPCB) and Aluminum base board is widely used, but during use, the performance of moisture resistance and chemical resistance is not good. High Tg circuit boards are most suitable.
When the temperature of a high Tg circuit board rises to a certain area, the substrate will change from the "glass state" to the "rubber state". The temperature at this time is called the glass transition temperature (Tg) of the board. That is, Tg is the highest temperature (°C) at which the base material maintains rigidity. That is to say, ordinary PCB substrate materials not only produce softening, deformation, melting and other phenomena at high temperatures, but also show a sharp decline in mechanical and electrical characteristics (I think you don't want to see this in your own products).

Generally, the Tg of the board is above 130 degrees, the high Tg is generally greater than 170 degrees, and the medium Tg is about greater than 150 degrees.
Usually PCB circuit boards with Tg ≥ 170°C are called high Tg circuit boards.
The Tg of the substrate is increased, and the characteristics of the heat resistance, moisture resistance, chemical resistance, and stability of the circuit board will be improved and improved. The higher the TG value, the better the temperature resistance of the board, especially in lead-free PCBA Manufacturing, where high Tg applications are more common.
High Tg refers to high heat resistance. With the rapid development of the electronics industry, especially the electronic products represented by computers, the development of high functionality and high multilayers requires higher heat resistance of PCB substrate materials as an important guarantee. The emergence and development of high-density mounting technology represented by Surface-Mount (SMT) & BGA Assembly and CMT has made PCBs more and more inseparable from the support of high heat resistance of substrates in terms of small aperture, fine circuit and thinner. 

Therefore, the difference between the general Ro4350B+FR4 hybrid Board and the high-Tg FR-4 is the mechanical strength, dimensional stability, adhesiveness, water absorption, and thermal decomposition of the material under heat, especially when heated after moisture absorption. There are differences in various conditions such as performance and thermal expansion. High Tg products are obviously better than ordinary PCB substrate materials. In recent years, the number of customers requiring high Tg circuit boards has increased year by year.