Why Should You Choose RO4835 Laminates for Your Next RF or Microwave PCB Project?

In the world of high-frequency printed circuit boards (PCBs), material selection plays a critical role in determining the overall performance, reliability, and longevity of the final product. Traditional thermoset laminate materials, such as FR-4, are prone to oxidation—especially under elevated temperatures. This oxidation can lead to undesirable increases in the dielectric constant (Dk) and dissipation factor (Df), ultimately compromising signal integrity and circuit performance.

Rogers Corporation’s RO4835 high-frequency laminate is specifically engineered to overcome these limitations. With superior resistance to oxidation and exceptional stability under thermal stress, Rogers RO4835 offers an ideal substrate solution for high-frequency and RF applications. What’s more, it delivers electrical and mechanical properties comparable to those of the widely used RO4350B laminates, but with enhanced cost-efficiency and compatibility with standard FR-4 manufacturing processes.

Key Features of RO4835 High Frequency Laminates

One of the standout attributes of Rogers 4835 PCB is its compliance with RoHS and UL 94 V-0 standards, making it both environmentally friendly and flame-retardant. This makes it suitable for use in demanding industries where safety and regulatory compliance are non-negotiable.

Another significant advantage is the availability of Rogers' proprietary LoPro™Reverse treated copper foil. This specialized foil treatment minimizes insertion loss, making RO4835 PCB an excellent choice for applications where signal integrity and low loss are paramount.

Electrical consistency is another area where RO4835 excels. It boasts a stable dielectric constant of 3.48 with very tight tolerances, ensuring predictable performance across various frequencies—a crucial factor in RF and microwave circuit design. Additionally, its dissipation factor is as low as 0.0037 at 10 GHz, meaning minimal signal loss even in high-frequency scenarios.

From a mechanical standpoint, RO4835 exhibits outstanding dimensional stability due to its low coefficient of thermal expansion (CTE). With CTE values of 10 ppm/°C in the X direction, 12 ppm/°C in the Y direction, and 31 ppm/°C in the Z direction, this material significantly reduces the risk of delamination or plated-through-hole failure under thermal cycling.

PCB Manufacturing Capabilities with RO4835

We support a wide range of PCB configurations using RO4835 substrates, including single-sided, double-sided, multi-layer, and hybrid constructions. This allows for design flexibility whether you are working on a simple RF switch or a complex phased-array radar system.

To accommodate diverse electrical requirements, we offer standard copper weights of 1oz (35µm) and 2oz (70µm). Dielectric thickness is also highly adaptable: for ED copper, thickness ranges from 6.6 mil (0.168 mm) to 60 mil (1.524 mm); for LoPro copper, it ranges from 4 mil (0.102 mm) to 60.7 mil (1.542 mm).

We can produce PCBs with maximum dimensions of 400mm x 500mm, suitable for both prototyping and volume production. A variety of solder mask colors—including green, black, blue, yellow, and red—are available to meet aesthetic or branding preferences.

Surface finish options are equally comprehensive, featuring bare copper, HASL (Hot Air Solder Leveling), immersion gold (ENIG), immersion silver, immersion tin, OSP (Organic Solderability Preservative), and pure gold plating. This ensures compatibility with virtually any assembly process and end-use environment.

Typical Applications

RO4835 high-frequency PCBs are ideally suited for a variety of advanced electronic applications, including:

• Automotive radar and sensor systems
• Point-to-point microwave communication links
• High-power amplifiers
• Phased-array radar systems
• General RF components and subsystems

Whether you are developing cutting-edge automotive safety systems, communication infrastructure, or defense electronics, RO4835 provides a reliable, high-performance foundation for your most demanding circuits.