New Developments in Transfer-Doped and Accumulation Channel Diamond Electronic Devices

Transfer-doping of diamond has proven to be an attractive alternative to substitutional doping of diamond for the production of high-performance diamond electronic devices, such as Field Effect Transistors. The process, which relies in a low/negative electron affinity chemical termination of the diamond surface e.g. with hydrogen, combined with the application of a surface electron acceptor material of sufficiently high electron affinity, generates a high carrier density, shallow, sub-surface 2D hole gas that may be exploited as a conductive channel in several device applications.<br/>Significant progress has been made recently in the further development of transfer doping processes in diamond, virtually eliminating previous issues such as inherent temperature and atmospheric sensitivity and associated instability. Through engineering of surface acceptor materials, charge mobility in the diamond has also seen significant improvement, leading to significant reduction in material resistivity. Alternative chemical surface terminations of diamond have also more recently demonstrated additional routes for the production of high performance electronic devices.<br/>This presentation will attempt to provide an overview of these recent and exciting developments in the diamond electronic devices, and speculate on future directions and the potential impact of this accelerating area of research.