Raman scattering in boron-doped single-crystal diamond used to fabricate Schottky diode detectors

Thanks to its exceptional physical and electronic properties, diamond is an attractive material for electronic devices working at high temperature and in harsh chemical environment. Its use as a semiconducting material for electronics is related to the possibility of doping it in order to control its conductivity. Semiconducting p-type diamond films can be grown when boron is introduced into the film. In this work, boron-doped (B-doped) homoepitaxial diamond films are grown by Microwave Plasma Enhanced Chemical Vapor Deposition. Raman and electrical characterizations are carried out on the films as a function of boron doping level. As the boron content increases, we observe systematic modifications in the Raman spectra of single-crystal diamonds. A significant change in the lineshape of the first-order Raman peak, as well as a wide and structured signal at lower wavenumbers, appears simultaneously in samples grown with higher boron content. A single crystal diamond Schottky diode based on a metal/intrinsic/p-type diamond junction is analysed.