Hello everyone,

Today, we’re going to introduce the high frequency PCB built on thermally conductive low loss material ---- RF-35TC PCB.

RF-35TC is a PTFE based, ceramic filled fiberglass laminate from Taconic company. It will not oxidize, yellow or show upward drift in dielectric constant and dissipation factor.

RF-35TC provides low dissipation factor with high thermal conductivity. The heat is diffused away from both transmission lines and surface mount components such as capacitors etc.

Now, let’s take a look at the data sheet of RF-35TC.

The first one is dielectric constant, with a value of 3.5. This is a low value in most high frequency PCBs. The DK is stable across a broad temperature range which is critical for both narrow band and broad band overlay couplers.

Next one is 0.0011 low dissipation factor, whereas RT/duroid 6035HTC is 0.0013, TC600 is 0.0017 and TC350 is 0.002 etc.

Dielectric breakdown is 56.7 kilo voltages, dielectric strength is 570 V/mil and arc resistance is 304 seconds. These are secure value for our electronics devices. Water absorption is 0.05%.

The thermal conductivity of RF-35TC is at high level, ranging from 0.87-0.92 W/mK with half ounces and 1 ounce copper. The extremely low Df and high thermal conductivity are particularly suited for power amplifier applications.

RF-35TC has very low coefficient thermal expansion (CTE) in X, Y and Z axis (11, 13 and 34 ppm/°C respectively). Low X and Y CTE values are crucial for maintaining critical distances between trace elements in printed filters,enhancing antenna gains and efficiencies.

Now, let’s take a look at our PCB capabilities on RF-35TC material.

For RF-35TC PCBs, we can provide you with single layer board, double layer board, multi-layer board and hybrid types. RF-35TC PCBs have wide thickness. These are the standard thickness such as 10 mils, 20 mils, 30 mils, and 60mils etc.

Finished copper on PCB can be 1oz and 2oz. Our maximum PCB size on high frequency materials is 400mm by 500mm, it can be a single board in the sheet and also can be different designs in this panel.

Solder mask of green, black, blue and yellow etc is available in house. There’s immersion gold, HASL, immersion silver, immersion tin, bare copper etc. for pads plating.

The basic colour of RF-35TC PCB is brown and gray.

We can also see the applications in couplers, antennas, power amplifiers and satellite equipment etc.

Like most material properties, there are many techniques for measuring thermal conductivity. Thermal conductivity measured on an unclad laminate offers the true thermal conductivity of the material. Measurements on a copper clad laminate (CCL) typically yield higher values as the CCL offers the least thermal resistance at the interface between the laminate and measuring equipment. When measured with or without copper cladding, RF-35TC PCB offers superior heat dissipation performance.