ENERGY-DEPENDENCE OF ELECTRON DAMAGE AND DISPLACEMENT THRESHOLD ENERGY IN 6H SILICON-CARBIDE

The frequency response of silicon carbide (SiC) light-emitting diodes has been used to measure the energy dependence of displacement damage produced in 6H SiC by energetic electrons. The minimum electron energy required to produce displacement damage was determined to be 108 +/- 7 keV, corresponding to an atomic displacement threshold energy, E(d), of 21.8 +/- 1.5 eV for the carbon atom. No evidence was seen of persistent damage due to displacement of silicon atoms. For electrons of energies greater than 0.5 MeV, the damage constant for lifetime degradation in SiC is lower than that for GaAs by more than three orders of magnitude, indicating a greatly superior resistance of SiC to displacement damage in most radiation environments.