SiC epitaxial wafer, semiconductor device, and power converter
AssigneeMitsubishi Electric Corporation
InventorsMasashi Sakai, Yoichiro Mitani
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Abstract
A SiC epitaxial wafer includes a SiC substrate and a SiC epitaxial layer disposed on the SiC substrate. The SiC epitaxial layer includes a high carrier concentration layer and two low carrier concentration layers having lower carrier concentration than the high carrier concentration layer, and being in contact with a top surface and a bottom surface of the high carrier concentration layer to sandwich the high carrier concentration layer. A difference in carrier concentration between the high carrier concentration layer and the low carrier concentration layers is 5×1014/cm3 or more and 2×1016/cm3 or less.
Claims8
A SiC epitaxial wafer comprising:
- a SiC substrate;
- and
- a SiC epitaxial layer disposed on the SiC substrate,
- wherein the SiC epitaxial layer includes a high carrier concentration layer, and two low carrier concentration layers having lower carrier concentration than the high carrier concentration layer, and
- being in contact with a top surface and a bottom surface of the high carrier concentration layer to sandwich the high carder concentration layer, and
- a difference between carrier concentration of the low carrier concentration layers in regions of contact with the high carrier concentration layer and a maximum value of carrier concentration of the high carrier concentration layer is 5×1014/cm3 or more and 2×1016/cm3 or less;
- wherein an occurrence of carrot defects in the SiC epitaxial layer is reduced by approximately 40% or more.
Dependencies are inferred from the claim text.