Patent ID: 9184230
Filing Date: 2015-11-10
Classification: H01L

Abstract:
1. A silicon carbide vertical field effect transistor comprising: a first-conductive-type silicon carbide substrate; a low-concentration first-conductive-type silicon carbide layer formed on a surface of the first-conductive-type silicon carbide substrate; second-conductive-type regions selectively formed on a surface of the low-concentration first-conductive-type silicon carbide layer; first-conductive-type source regions formed in the second-conductive-type regions; a high-concentration second-conductive-type region formed between the first-conductive-type source regions on the second-conductive-type region; a source electrode electrically connected directly to the high-concentration second-conductive-type region and a first-conductive-type source region among the first-conductive-type source regions; a gate insulating film formed from a first first-conductive-type source region to an adjacent second first-conductive-type source region of the first-conductive-type source regions and over a respective first second-conductive-type region and a respective second second-conductive-type region of the second-conductive-type regions and over the first-conductive-type silicon carbide layer; a gate electrode formed on the gate insulating film; a drain electrode on a back side of the first-conductive-type silicon carbide substrate, wherein a second high-concentration second-conductive-type region is disposed between the first-conductive-type silicon carbide layer and each of the second-conductive-type regions; a width of the second high-concentration second-conductive-type region is smaller than that of the second-conductive-type regions; and, the second high-concentration second-conductive-type region overlaps the high-concentration second-conductive-type region.