Silicon carbide semiconductor device and process for manufacturing same
First Claim
1. A silicon carbide semiconductor device, comprising:
- a single crystal silicon carbide semiconductor substrate comprising a stack of a first semiconductor layer of a first conductive-type, a second embodiment layer of the first conductive-layer having an electric resistance higher than that of said first semiconductor layer, and a third semiconductor layer of a second conductive-type different from the first conductive-type in this order from the bottom to the top thereof, and single crystal silicon carbide semiconductor substrate having a main surface on a side of said third semiconductor layer;
a first semiconductor region of the first conductive-type formed in a predetermined region of said third semiconductor layer;
a trench extending from said main surface through said first semiconductor region and said third semiconductor layer and reaching said second semiconductor layer, said trench having a side wall exposing said first semiconductor region and said third semiconductor layer and a bottom exposing said second semiconductor layer;
an island semiconductor region comprising said first semiconductor region and said third semiconductor layer and entirely surrounded by said trench so as to be separated from any other island semiconductor regions;
a gate insulating layer formed on the side wall of said island semiconductor region;
a gate electrode layer formed on said gate insulating layer;
a first electrode layer formed on at least a portion of said first semiconductor region; and
a second electrode layer formed on a surface of said first semiconductor layer.
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Accused Products
Abstract
A n- -type source region 5 is formed on a predetermined region of the surface layer section of the p-type silicon carbide semiconductor layer 3 of a semiconductor substrate 4. A low-resistance p-type silicon carbide region 6 is formed on a predetermined region of the surface layer section in the p-type silicon carbide semiconductor layer 3. A trench 7 is formed in a predetermined region in the n+ -type source region 5, which trench 7 passes through the n+ -type source region 5 and the p-type silicon carbide semiconductor layer 3, reaching the n- -type silicon carbide semiconductor layer 2. The trench 7 has side walls 7a perpendicular to the surface of the semiconductor substrate 4 and a bottom side 7b parallel to the surface of the semiconductor substrate 4. The hexagonal region surrounded by the side walls 7a of the trench 7 is an island semiconductor region 12. A high-reliability gate insulating film 8 is obtained by forming a gate insulating layer on the side walls 7a which surround the island semiconductor region 12.
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Citations
7 Claims
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1. A silicon carbide semiconductor device, comprising:
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a single crystal silicon carbide semiconductor substrate comprising a stack of a first semiconductor layer of a first conductive-type, a second embodiment layer of the first conductive-layer having an electric resistance higher than that of said first semiconductor layer, and a third semiconductor layer of a second conductive-type different from the first conductive-type in this order from the bottom to the top thereof, and single crystal silicon carbide semiconductor substrate having a main surface on a side of said third semiconductor layer; a first semiconductor region of the first conductive-type formed in a predetermined region of said third semiconductor layer; a trench extending from said main surface through said first semiconductor region and said third semiconductor layer and reaching said second semiconductor layer, said trench having a side wall exposing said first semiconductor region and said third semiconductor layer and a bottom exposing said second semiconductor layer; an island semiconductor region comprising said first semiconductor region and said third semiconductor layer and entirely surrounded by said trench so as to be separated from any other island semiconductor regions; a gate insulating layer formed on the side wall of said island semiconductor region; a gate electrode layer formed on said gate insulating layer; a first electrode layer formed on at least a portion of said first semiconductor region; and a second electrode layer formed on a surface of said first semiconductor layer. - View Dependent Claims (2, 3, 4, 5, 6, 7)
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Specification