Why are High-Frequency PCBs So "Delicate"?

The Material are crucial.

Commonly used substrates for high-frequency PCBs mainly include two types:

PTFE (Polytetrafluoroethylene): With a dielectric constant of approximately 2.1 and an extremely low loss tangent(under 0.001), it is the premier choice for millimeter-wave radar and satellite communication.

RO4000 Series (e.g., RO4350B): Dielectric constant of about 3.48, loss factor of 0.0037. It offers high cost-effectiveness and relatively easy to process, making it highly suitable for applications such as 5G base stations and automotive electronics.

These materials are not only expensive but also challenging to process, requiring specialized equipment and techniques to handle effectively.

Core Processes in High-Frequency PCB Manufacturing

Drilling Technology: We employ a combination of laser drilling and mechanical drilling, achieving a minimum hole diameter of 0.075mm—thinner than a human hair!

Hole Metallization: PTFE materials require plasma treatment or sodium naphthalene activation to ensure proper copper deposition in the holes, which is critical for reliability.

Circuit Patterning: Utilizes LDI (Laser Direct Imaging) exposure systems to directly image circuits onto the PCB via laser scanning, eliminating the need for masks and achieving precision up to ±10μm.

Impedance Control: High-frequency signals are extremely demanding regarding impedance matching. The tolerance must be maintained within ±5%; otherwise, signal integrity will suffer from severe distortion.

Applications of High-Frequency PCBs

✅ 5G Communication Equipment: RF front-ends, antennas, microwave modules

✅ Automotive Electronics: Millimeter-wave radar, ADAS (Advanced Driver-Assistance Systems)

✅ Satellite Communications: Microwave transmission, radar systems

✅ Data Centers: High-speed servers, switch backplanes