Progress in Growth of Thick Epitaxial Layers on 4 Degree Off-Axis 4H SiC Substrates

This paper reports the progress of the thick epitaxy development at Dow Corning. Epiwafers with thickness of 50 - 100 mu m have been grown on 4 degrees off-axis 76mm 4H SiC substrates. Smooth surface with RMS roughness below 1nm and defect density down to 2 cm(-2) are achieved for 80 - 100 mu m thick epiwafers. Long carrier lifetime of 2 - 4 mu s are routinely obtained, and low BPD density in the range of 50 down to below 10 cm(-2) is confirmed. High voltage JBS diodes have been successfully fabricated on these wafers with thick epitaxial layers.