Radiation damage on 6H-SiC Schottky diodes

The radiation damage production rate in SiC Schottky diodes was studied by measuring the ion beam induced charge (IBIC) from a 2 MeV He+ ion microbeam. Two 30 mum diameter SiC Schottky diodes with a Ni Schottky contact were fabricated on 5 mum thick epilayers of both n-type and p-type 6H-SiC. An area of 10 mum x 10 mum on each Schottky diode was irradiated by a scanned 2 MeV He+ ion beam focused to less than 1 ltm in diameter with a dose range from 1 x 10(9) to 1 x 10(13) ions/cm(2). Before and after He+ ion beam irradiation, IBIC spectra were measured at the irradiated area. From these spectra, the relationship between the IBIC peak shift and the He+ ion beam dose was measured. For the n-type and p-type diodes, the IBIC pulse height was found to decrease from the initial height by 27% at 7.6 x 10(11) ions/cm(2) irradiation and 29% at 1.1 x 10(11) ions/cm(2), respectively. (C) 2003 Elsevier B.V. All rights reserved.