6H-SiC epilayers as nuclear particle detectors

Schottky diodes based on the n-n(+) 6H-SiC epilayers grown by sublimation e pitaxy and also the layers produced by CREE company (USA) were used as dete ctors of alpha-particles of spontaneous decay. Since the thickness of n-lay ers was smaller than the range of the particles, geometrical parameters of the experiment differed from conventional ones; in the latter case, a parti cle is brought to rest in the region of electric field in the detector. The calculated and experimental data were compared to study the special featur es of transport of nonequilibrium charge under the conditions of complete a nd partial depletion of the structure. It is shown that characteristics of the material that govern the transport of charge carriers can be deduced fr om the analysis of the behavior of the signal amplitude and the shape of th e pulse-height spectrum in relation to bias voltage applied to the Schottky diode. It follows from the results that the present-day sublimation-grown SiC layers are suitable for use as the basis for fabrication of nuclear par ticle detectors. (C) 2000 MAIK "Nauka/Interperiodica".