Comparative study of transient current induced in SiC p +n and n +p diodes by heavy ion micro beams

Abstract

N +p and p +n diodes were fabricated on p- and n-type 6H–SiC substrates with epitaxial layers, respectively. The charge induced in the diodes by 9 MeV oxygen (O) and nickel (Ni) ions was measured using Transient Ion Beam Induced Current (TIBIC) to clarify the capability of these diodes as particle detectors. As a result of the TIBIC measurements using 9 MeV O, the Charge Collection Efficiency (CCE) of around 83% was obtained for both p +n and n +p diodes. Since the CCE value includes the consumption of incident ion energy in an Al electrode and the n + (p +) region as well as the decay of charge in the measurement system, the CCE value obtained in this study indicates that SiC n +p as well as p +n diodes are suitable for particle detectors. On the other hand, in the case of 9 MeV Ni ion irradiation, the CCE for both n +p and p +n diodes decreases due to the Auger recombination in dense electron–hole pairs.