Radiation hardness of n-type SiC Schottky barrier diodes irradiated with MeV He ion microbeam

Pastuovi, *; Capan, I.*; Cohen, D.*; Forneris, J.*; Iwamoto, Naoya*; Oshima, Takeshi; Siegele, R.*; Hoshino, Norihiro*; Tsuchida, Hidekazu*

The relationship between defects created in SiC semiconductors and the degradation of SiC particle detectors was investigated. The n-type Schottky barrier diodes (SBD) fabricated on an epitaxial 4H-SiC layer were irradiated with a raster scanned alpha particle microbeam (either 2 or 4 MeV He ions) to introduce crystal damage with different depths. Deep level transient spectroscopy (DLTS) was applied to characterize defects generated in SiC by He ion irradiation. Ion Beam Induced Charge (IBIC) microscopy was used to determine the degradation of the charge collection efficiency (CCE). DLTS and electrical characteristics measurements suggested that minority carrier lifetime decreased with increasing the concentration of Z defect. Also, the free carrier concentration in SiC decreased with increasing He fluence. Furthermore, the formation of new type of defects, i.e. complex (cluster) defects was detected. In conclusion, the value of CCE decreased due to above-mentioned effects.