Use of Synthetic Graphite in High Performance RF and Microwave PCBs

The continued advances in miniaturization of electronic devices increases the challenges in managing waste heat. With active semiconductor devices becoming significant sources of heat, the printed circuit board (PCB) is asked to play multiple roles – to supply power to the device; to pass the increasingly high-speed signals between devices with as little loss as possible; and also, to play a significant part in passing heat energy away from such devices. In recent consumer electronics such as smartphones, the task of heat dissipation is not left solely to the PCB; areas of high heat concentration are also managed using pre-formed adhesive pads made from synthetic graphite, a good dissipator of heat. These are used to spread the heat energy over a wide area, reducing the temperature-induced stress on individual devices such as power amplifiers, improving life expectancy. Synthetic graphite has some appealing properties as we’ll see later.