microwave & rf pcb guide

High-Frequency PCB Product Showcase High-Frequency PCB, RF PCB & Microwave PCB Products

KKPCB is a leading manufacturer of high-frequency PCBs, offering a full range of rigid, flexible, rigid-flex, HDI, RF, microwave, multilayer, hybrid, and ATE high-frequency boards for demanding applications such as 5G, telecommunications, radar, satellite, automotive radar, IoT, and high-speed data communication. Using advanced materials like Rogers, Taconic, Arlon, Isola, Teflon, Dupont, and Shengyi, our PCBs provide low dielectric constant (Dk), low dissipation factor (Df), low thermal expansion (CTE), precise impedance control, and minimal signal loss. With rigorous quality control, advanced manufacturing processes, and engineering expertise, KKPCB delivers customized, reliable, and high-performance high-frequency PCB solutions that meet the most demanding project requirements.

What is a High-Frequency PCB?

High-frequency PCB board or RF microwave PCB refers to the special circuit board with high electromagnetic frequency, which is used for high frequency (frequency greater than 300MHz or wavelength less than 1m). Generally speaking, a high-frequency board can be defined as a circuit board with a frequency above 1GHz. Substrate materials need to have excellent electrical properties and good chemical stability. With the increase of power signal frequency, the loss requirement on the substrate is very small, so the importance of high-frequency material is highlighted.

High-frequency PCB board with induction heating technology has been widely used in the communication industry, network technology, and high-speed information processing system, which meets the requirements of many high-precision parameter instruments. A reliable high-frequency circuit board, in the actual production, provides great help.

High-frequency PCB is widely used in RF and Microwave PCB.High-frequency PCB materials are different from conventional FR4 materials. Most of them use PTFE &Teflon materials. Good electrical properties and low signal loss are the basis.

High-frequency PCB needs special materials to realize the high-frequency signal provided by this type of printed circuit board. Many PCB designers choose Rogers dielectric material because of its lower dielectric and signal loss, lower circuit manufacturing cost, and more suitable for rapid turnover prototype application.In addition to selecting the right PCB material and determining the correct Er value, the designer should also consider the conductor width and spacing, substrate constant, and other parameters. The highest level of process control must be used to specify and implement these parameters precisely.KKPCB is an experienced full-service high-frequency PCB manufacturer, which can provide reliable and excellent high-frequency PCB fabrication services. Evaluate your requirements according to your design, rich variety of high-frequency materials, mature high-frequency PCB manufacturing experience.

KKPCB is an experienced full-service high-frequency PCB manufacturer, which can provide reliable and excellent high-frequency PCB fabrication services. Evaluate your requirements according to your design, mature high-frequency PCB manufacturing experience. Professional production experience for high frequency circuit boards used in power divider, coupling and device, circuit builder, amplifier, dry release, base station 3G antenna. Company year-round stocks domestic and imported high-frequency material (F4B Rogers, TACO, NC,ARLON, TP-2) dielectric constant 22106, etc. Can provide fast sample service and mass production in time to meet your diverse, multi-variety needs.

What are the advantages of high-frequency PCB?

High Efficiency

High-frequency Printed Circuit Boards with a low dielectric constant exhibit minimal signal loss. Combined with advanced induction heating technology, they achieve precise target heating with exceptional efficiency. In addition to high performance, these boards are environmentally friendly, aligning with the sustainable development trends of modern society.

Fast Signal Transmission

The signal transmission speed is inversely proportional to the square root of the dielectric constant, meaning lower dielectric constants result in faster signal propagation. High-frequency PCBs use specialized materials that not only ensure a small dielectric constant but also maintain stable operation, which is critical for high-speed and reliable signal transmission.

Precise and Flexible Regulation

High-frequency circuit boards are widely applied in precision heating of metal components across various industries. They can deliver localized or deep-level heating with exceptional accuracy, allowing both surface and internal component treatment, as well as focused or dispersed energy application, providing unmatched control and adaptability.

Superior Environmental Tolerance

The performance of conventional PCBs can be compromised by humidity and adverse environmental conditions. High-frequency PCBs made from low water absorption materials can withstand these challenges. In addition, they offer chemical corrosion resistance, moisture resistance, high-temperature stability, and excellent peel strength, ensuring consistent, reliable performance in demanding environments.

Processing characteristics of high-frequency PCB

High-frequency Printed Circuit Boards (PCBs) have strict fabrication requirements due to their specialized materials and high-performance applications:

• Precise Impedance Control: Line width tolerances are typically 5–8%, making accurate trace and spacing control critical for reliable signal transmission.
• PTH Copper Adhesion: Due to the unique substrate materials, adhesion of plated through-hole (PTH) copper is relatively low. Plasma treatment is often used to roughen via holes and board surfaces to improve adhesion of copper and solder mask. Grinding the board before solder mask application is not recommended; micro-etching solutions are preferred for surface preparation.
• Specialized Milling Requirements: Most high-frequency PCB substrates are made from polytetrafluoroethylene (PTFE), which can produce burrs if milled with standard cutters. Specialized milling cutters are required to ensure clean edges and precise dimensions.
• High Physical and Technical Demands: These PCBs require excellent dimensional stability, material integrity, and precise technical parameters, making them suitable for automotive collision avoidance systems, satellite communication, RF devices, and other high-performance electronic applications.

These processing characteristics underscore the need for advanced manufacturing techniques and experienced PCB fabrication expertise to ensure high-quality, reliable high-frequency PCBs.

Application field of high-frequency PCB

• Mobile communication products, intelligent lighting system
• Power amplifier, low noise amplifier, etc
• Power divider, coupler, duplexer, filter, and other passive components
• In the fields of automobile anti-collision systems, satellite systems, and radio systems, the high frequency of electronic equipment is the development trend.

Classification of high-frequency PCB material

1. Powder Ceramic-Filled Thermosetting Materials

A. Representative Manufacturers / Materials

• Rogers: 4350B, 4003C
• Arlon: 25N, 25FR
• Taconic: TLG Series

B. Processing Characteristics

• Similar to epoxy resin / glass fiber woven fabric (FR4).
• Board is brittle, prone to breakage.
• Drilling and routing (gonging) reduce tool life by ~20% (drill bits, router bits).

2. PTFE-Based Materials

A. Representative Manufacturers / Materials

• Rogers: RO3000 Series, RT Series, TMM Series
• Arlon: AD / AR Series, Isoclad Series, Cuclad Series
• Taconic: RF Series, TLX Series, TLY Series
• Taixing Microwave: F4B, F4BM, F4BK, TP-2

B. Processing Guidelines

1. Cutting

• Keep protective film during cutting to prevent scratches and dents.

2. Drilling

• Use new drill bits (standard 130° tip).
• Presser foot pressure: ~40 psi.
• Aluminum sheet as cover board, 1.0 mm melamine board as backing.
• After drilling, blow out dust from holes with compressed air.
• Ensure stable drilling machine; adjust drilling speed:
  • Smaller holes → higher drilling speed.
  • Smaller chip load → slower return speed.

3. Hole Treatment

• Plasma treatment or sodium etching improves hole wall activation and metallization.

4. PTH Copper Deposition

• After micro-etching (etch rate ~20 μin), proceed with PTH.
• Panels should be fed from the oil cylinder after PTH pulling.
• If required, apply a second PTH; feeding must still start from the predicted cylinder.

5. Soldermask Application

• Pretreatment: acid wash only, no mechanical scrubbing.
• After pretreatment: bake boards at 90 °C for 30 min before applying soldermask.
• Curing in 3 stages:
  • 80 °C for 30 min
  • 100 °C for 30 min
  • 150 °C for 30 min
• If surface oil contamination occurs, rework is possible: strip soldermask, reactivate, and reapply.

6. Routing (Gong Board)

• Cover PTFE surface with white paper, clamp with FR-4 or phenolic backboard (≥1.0 mm).
• After routing, carefully scrape burrs on the backboard by hand to avoid substrate or copper damage.
• Separate boards with sulfur-free paper and perform visual inspection to minimize burrs.
• Key point: ensure clean edge removal during routing to protect PTFE substrate and copper foil.

List of common high speed and high-frequency PCB material parameters