RF Sputtered h-BN Thin Film Layer for Printed Circuit Boards as an Insulating Layer

Power electronic devices are usually bulk in size due to the power management systems in them. In normal power electronic devices, the heat sink is used to reduce the temperature in the circuit. The heat sink used is normally larger in size and surface area because large heat sinks have higher convective heat transfer capability. The size reduction of the device is not possible with such large heat sinks; therefore, we need to avoid them. Here, we are trying to create a printed circuit board (PCB) that can also act as a heat sink. This approach will help to reduce device size by avoiding large heat sinks. In this paper, for making thermally conductive PCB, we need a thermally conductive base. Highly insulative Hexagonal boron nitride(h-BN) is thin filmed on a copper plate using RF sputtering. Then we determined the quality of different thickness of h-BN film by finding band gap energy using UV-Vis spectroscopy and also determined the resistance of the films. From the results, it is found that the RF sputtering is not critically affect the quality of h-BN film and the resistance of the layer increases with thickness. So, the h-BN coated copper sheet using RF sputtering can act as a good thermally conductive and electrically nonconductive PCB. In addition, it has very low cost and uses eco-friendly materials and fabrication process.