Doped Wide Bandgap Materials and Devices from Semiconducting Boron Carbide

Abstract

Semiconducting boron carbide is showing promise as a refractory and robust material with a tunable bandgap. Thin films and devices are easily grown with standard chemical vapor deposition techniques using a variety of boron and carbon precursors including the closo-dodecacarboranes (C2B10H12). Although undoped boron carbide films grown from orthocarborane (1,2- C2B10H12) are p-type, those grown from metacarborane (1,7- C2B10H12) and paracarborane (1,12-C2B10H12) are n-type allowing the production of all boron carbide diodes. In this experimental study, new precursors are used that contain phosphorus and yield new doped n-type films on deposition. The films were characterized by a variety of techniques using UV-Vis spectroscopy (optical bandgap), photoemission (PES) and inverse photoemission (IPES) (electronic structure) and FTIR spectroscopy. Performance evaluation of these new materials will be compared with previous materials.