Study on the Surface Charge Transfer Doping of Cubic Boron Nitride (cBN) Films

Cubic boron nitride (cBN) is a very promising wide bandgap semiconductor for applications in high-temperature, high-power electronic devices. However, the related research is still in its infancy due to the difficulties in synthesizing high-quality cBN films and controlling their electrical conductivity. In this project we propose a new approach to tune the surface conductivity of cBN films by employing the surface charge transfer mechanism. The proposal is based upon our extensive research on the growth of cBN films in halogenated plasmas and studies on their electronic properties. A variety of surface coating materials including C60, F4- TCNQ, and MoO3, will be employed, and the influence of the surface termination and coverage/thickness of the coating materials on the electrical properties of cBN films will be systematically investigated. The variation of the electronic structure of cBN upon surface coatings will be further identified, and prototypes of cBN-based field effect transistor will be constructed.