Sumitomo Electric Industries, Limited

Taro Nishiguchi

Shin Harada

Shinsuke Fujiwara

Makoto Sasaki

Keiji Wada

Tsutomu Hori

Yasuo Namikawa

Hironori Itoh

Kyoko Okita

Jun Genba

Yu Saitoh

Hirofumi Yamamoto

Hideyuki Doi

Toru Hiyoshi

Tomihito Miyazaki

Hiroki Inoue

Tomoaki Hatayama

Kenji Kanbara

So Tanaka

Taku Horii

Kosuke Uchida

Ryosuke Kubota

Shunsaku Ueta

Takaya Miyase

Akira Matsushima

Takemi Terao

Naoki Ooi

Taro Enokizono

Hiroki Nishihara

A silicon carbide epitaxial substrate includes a silicon carbide substrate, a silicon carbide epitaxial film. The silicon carbide epitaxial film is on the silicon carbide substrate. The first extended defect is in the silicon carbide epitaxial film. The first extended defect includes a particle, a triangular defect extending from the particle along an off-direction, and a basal plane dislocation originating from the particle and having a portion extending along a direction perpendicular to each of a thickness direction of the silicon carbide substrate and the off-direction. In the direction perpendicular to each of the thickness direction of the silicon carbide substrate and the off-direction, an extended width of the basal plane dislocation is twice or more a base width of the triangular defect. In a second main surface, an area density of the basal plane dislocation included in the first extended defect is 3/cmor less.

Silicon carbide epitaxial substrate

A silicon carbide epitaxial substrate includes a silicon carbide substrate, a first silicon carbide epitaxial layer, and a second silicon carbide epitaxial layer. The silicon carbide substrate has a first main surface and a second main surface opposite to the first main surface. The first silicon carbide epitaxial layer is in contact with a whole of the first main surface. The second silicon carbide epitaxial layer is in contact with a whole of the second main surface. A carrier concentration of the silicon carbide substrate is higher than a carrier concentration of each of the first silicon carbide epitaxial layer and the second silicon carbide epitaxial layer.

A silicon carbide epitaxial substrate includes a silicon carbide single crystal substrate and a silicon carbide layer. In a direction parallel to a central region, a ratio of a standard deviation of a carrier concentration of the silicon carbide layer to an average value of the carrier concentration of the silicon carbide layer is less than 5%. The average value of the carrier concentration is more than or equal to 1&#xd7;10cmand less than or equal to 5&#xd7;10cm. In the direction parallel to the central region, a ratio of a standard deviation of a thickness of the silicon carbide layer to an average value of the thickness of the silicon carbide layer is less than 5%. The central region has an arithmetic mean roughness (Sa) of less than or equal to 1 nm. The central region has a haze of less than or equal to 50.

Silicon carbide epitaxial substrate and method for manufacturing silicon carbide semiconductor device

A silicon carbide substrate capable of stably forming a device of excellent performance, and a method of manufacturing the same are provided. A silicon carbide substrate is made of a single crystal of silicon carbide, and has a width of not less than 100 mm, a micropipe density of not more than 7 cm, a threading screw dislocation density of not more than 1&#xd7;10cm, a threading edge dislocation density of not more than 1&#xd7;10cm, a basal plane dislocation density of not more than 1&#xd7;10cm, a stacking fault density of not more than 0.1 cm, a conductive impurity concentration of not less than 1&#xd7;10cm, a residual impurity concentration of not more than 1&#xd7;10cm, and a secondary phase inclusion density of not more than 1 cm.

Silicon carbide substrate and method of manufacturing the same

A silicon carbide epitaxial substrate has a silicon carbide single-crystal substrate and a silicon carbide layer. An average value of carrier concentration in the silicon carbide layer is not less than 1&#xd7;10cmand not more than 5&#xd7;10cm. In-plane uniformity of the carrier concentration is not more than 2%. The second main surface has: a grooveextending in one direction along the second main surface, a width of the groove in the one direction being twice or more as large as a width thereof in a direction perpendicular to the one direction, and a maximum depth of the groove from the second main surface being not more than 10 nm; and a carrot defect. A value obtained by dividing a number of the carrot defects by a number of the grooves is not more than 1/500.

Silicon carbide epitaxial substrate having grooves extending along main surface and method of manufacturing silicon carbide semiconductor device

A semiconductor device has a semiconductor layer and a substrate. The semiconductor layer constitutes at least a part of a current path, and is made of silicon carbide. The substrate has a first surface supporting the semiconductor layer, and a second surface opposite to the first surface. Further, the substrate is made of silicon carbide having a 4H type single-crystal structure. Further, the substrate has a physical property in which a ratio of a peak strength in a wavelength of around 500 nm to a peak strength in a wavelength of around 390 nm is 0.1 or smaller in photoluminescence measurement. In this way, the semiconductor device is obtained to have a low on-resistance.

Semiconductor device and method for manufacturing same

A semiconductor stack includes a substrate made of silicon carbide, and an epi layer disposed on the substrate and made of silicon carbide. An epi principal surface, which is a principal surface opposite to the substrate, of the epi layer is a carbon surface having an off angle of 4&#xb0; or smaller relative to a c-plane. In the epi principal surface, a plurality of first recessed portions having a rectangular circumferential shape in a planar view is formed. Density of a second recessed portion that is formed in the first recessed portions and is a recessed portion deeper than the first recessed portions is lower than or equal to 10 cmin the epi principal surface.

Semiconductor stack

An epitaxial wafer includes a silicon carbide film having a first main surface. A groove portion is formed in the first main surface. The groove portion extends in one direction along the first main surface. Moreover, a width of the groove portion in the one direction is twice or more as large as a width of the groove portion in a direction perpendicular to the one direction. Moreover, a maximum depth of the groove portion from the first main surface is not more than 10 nm.

Epitaxial wafer and method for manufacturing same

A semiconductor stack includes a substrate made of silicon carbide, and an epi layer disposed on the substrate and made of silicon carbide. An epi principal surface, which is a principal surface opposite to the substrate, of the epi layer is a carbon surface having an off angle of 4&#xb0; or smaller relative to a c-plane. In the epi principal surface, a plurality of first recessed portions having a rectangular circumferential shape in a planar view is formed. Density of a second recessed potion that is formed in the first recessed portions and is a recessed portion deeper than the first recessed portions is lower than or equal to 10 cmin the epi principal surface.

A silicon carbide epitaxial substrate has a silicon carbide single-crystal substrate and a silicon carbide layer. An average value of carrier concentration in the silicon carbide layer is not less than 1&#xd7;10cmand not more than 5&#xd7;10 cm. In-plane uniformity of the carrier concentration is not more than 2%. The second main surface has: a grooveextending in one direction along the second main surface, a width of the groove in the one direction being twice or more as large as a width thereof in a direction perpendicular to the one direction, and a maximum depth of the groove from the second main surface being not more than 10 nm; and a carrot defect. A value obtained by dividing a number of the carrot defects by a number of the grooves is not more than 1/500.

Silicon carbide epitaxial substrate having a silicon carbide layer and method of manufacturing silicon carbide semiconductor device

A semiconductor stack includes a substrate made of silicon carbide, and an epi layer disposed on the substrate and made of silicon carbide. An epi principal surface, which is a principal surface opposite to the substrate, of the epi layer is a carbon surface having an off angle of 4&#xb0; or smaller relative to a c-plane. In the epi principal surface, a plurality of first recessed portions having a rectangular circumferential shape in a planar view is famed. Density of a second recessed portion that is formed in the first recessed portions and is a recessed portion deeper than the first recessed portions is lower than or equal to 10 cmin the epi principal surface.

A silicon carbide epitaxial substrate includes a silicon carbide single crystal substrate and a silicon carbide layer. The silicon carbide single crystal substrate has a first main surface. The silicon carbide layer is on the first main surface. The silicon carbide layer includes a second main surface opposite to a surface thereof in contact with the silicon carbide single crystal substrate. The second main surface has a maximum diameter of more than or equal to 100 mm. The second main surface includes an outer peripheral region which is within 3 mm from an outer edge of the second main surface, and a central region surrounded by the outer peripheral region. The central region has a haze of less than or equal to 75 ppm.

A method for manufacturing a silicon carbide epitaxial substrate includes epitaxially growing a first layer on a silicon carbide single crystal substrate, and forming a second layer at an outermost surface of the first layer. The second layer has a chemical composition or density different from that of the first layer. A ratio of a thickness of the second layer to a thickness of the first layer is more than 0% and less than or equal to 10%.

Method for manufacturing silicon carbide epitaxial substrate, silicon carbide epitaxial substrate, method for manufacturing silicon carbide semiconductor device, and silicon carbide semiconductor device

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Itami, Japan

Taro Nishiguchi