What is High Frequency (HF) PCB?

Electronic gadgets with excessive frequency is the growing tendency nowadays, specially in wi-fi network. Satellite conversation developing rapidly, statistics merchandise pass in the direction of excessive velocity and excessive frequency. Thus growing new merchandise usually want to apply excessive frequency substrate, satellite tv for pc system, cellular smartphone receiving base station and so on, those conversation merchandise have to use excessive frequency PCB.

The functions of excessive frequency PCB.

1. DK need to be small and solid enough, generally the smaller the higher, excessive DK might also additionally result in sign transmission delay.

2. DF need to be small, which especially have an effect on nice of sign transmission, the smaller DF should make smaller sign wastage accordingly.

3. The thermal expansivity need to be the equal with copper foil as a whole lot as possible, due to the fact the distinction will result in copper foil separated withinside the modifications of bloodless and warmth.

4. Water absorptivity have to be low, excessive water absorptivity will have an effect on DK and DF while withinside the moist environment.

5. Heat resisting assets, chemistry resisting, effect endurance, peel off resisting have to be good.

Materials used for HF circuit board.

High-frequency board for wi-fi packages and records costs withinside the higher GHz variety have unique needs at the fabric used:

1. Adapted permittivity.

2.Low attenuation for green sign transmission.

3.Homogeneous production with low tolerances in insulation thickness and dielectric constant.

Generally speaking, excessive frequency may be described as frequency above 1GHz. Currently, PTFE fabric is broadly utilized in high frequency PCB manufacturing, it`s additionally known as Teflon, which frequency is commonly above 5GHz. In addition, FR4 or PPO substrate may be used to the product frequency amongst 1GHz~10GHz. These 3 excessive frequency substrate have under differences:

With regard to laminate value of FR4, PPO and Teflon, FR4 is the most inexpensive one, even as Teflon is the maximum high priced one. In phrases of DK, DF, water absorption and frequency feature, Teflon is the best. When product utility require frequency above 10GHz, most effective are we able to select Teflon PCB substrate to manufacture. Obviously, the overall performance of Teflon is a long way higher than different substrate, However, Teflon substrate has the downside of excessive value and massive warmness resisting assets. In order to enhance PTFE stiffness and warmth resisting assets function, a massive range of SiO2 or fiber glass because the filling fabric. On the opposite hand, because of molecule inertia of PTFE fabric, which it isn't smooth to mix with copper foil, thus, it wishes to do unique floor remedy at the mixture side. With regard to mixture floor remedy, commonly use chemical etching on PTFE floor or plasma etching to plus floor roughness or upload one adhesive movie among PTFE and copper foil, however those might also additionally have affect on dielectric overall performance.