DEEP-LEVEL DEFECTS IN ELECTRON-IRRADIATED 4H SIC EPITAXIAL LAYERS

Deep level defects in electron-irradiated 4H SiC epitaxial layers grow n by chemical vapor deposition were studied using deep level transient spectroscopy. The measurements performed on electron-irradiated p(+)n junctions in the temperature range 100-750 K revealed several electro n traps and one hole trap with thermal ionization energies ranging fro m 0.35 to 1.65 eV. Most of these defects were already observed at a do se of irradiation as low as approximate to 5 x 10(13) cm(-2). Dose dep endence and annealing behavior of the defects were investigated. For t wo of these electron traps, the electron capture cross section was mea sured. From the temperature dependence studies, the capture cross sect ion of these two defects are shown to be temperature independent. (C) 1997 American Institute of Physics.