Low-compensated boron-doped homoepitaxial diamond films

Abstract

Abstract We have synthesized device grade B-doped homoepitaxial diamond films with low compensation using a microwave plasma chemical vapor deposition (CVD) system. This study was based on an approach in which the synthesis of device grade films was performed in a clean CVD system. Among the films studied here, Hall effect measurements showed that the highest values of Hall mobility were 1840 cm 2 /V s at 290 K. The donor (compensation) concentration N D and compensation ratio N D / N Acceptor of the film mentioned above were 4±1×10 14 cm −3 and about 0.4%, respectively. Furthermore, as a result of applying the two-step growth method to B-doped films, we obtained B-doped films without unepitaxial crystallites and pyramidal hillocks. We made high-quality Schottky junctions between the metal (Al, Cr, Ni, Au, or Pt) and the present B-doped diamond films. The current–voltage characteristics of these junctions indicated high-rectification properties with ideality factor n ∼1.1 and very low leakage currents at reverse bias. In particular, the junction fabricated with Pt was operational with n ∼1.3 at high temperature of around 731 K.