Denso Corporation

Toyota Jidosha Kabushiki Kaisha

Denso Corpora Tion

Naohiro Suzuki

Yukihiko Watanabe

Eiichi Okuno

Narumasa Soejima

Hidefumi Takaya

Jun Morimoto

Hideo Matsuki

Yuichi Takeuchi

Masahiro Sugimoto

Tsuyoshi Ishikawa

Hitoshi Yamaguchi

Akitaka Soeno

Tsuyoshi Yamamoto

Jun Sakakibara

Toshimasa Yamamoto

Sachiko Aoi

Toshiyuki Morishita

Hiroki Nakamura

Takeo Yamamoto

Takeshi Endo

Yuuichi Takeuchi

Kensaku Yamamoto

Nobuyuki Kato

Masaki Konishi

Yoshitaka Noda

An SiC semiconductor device has a p type region including a low concentration region and a high concentration region filled in a trench formed in a cell region. A p type column is provided by the low concentration region, and a ptype deep layer is provided by the high concentration region. Thus, since a SJ structure can be made by the p type column and the n type column provided by the n type drift layer, an on-state resistance can be reduced. As a drain potential can be blocked by the ptype deep layer, at turnoff, an electric field applied to the gate insulation film can be alleviated and thus breakage of the gate insulation film can be restricted. Therefore, the SiC semiconductor device can realize the reduction of the on-state resistance and the restriction of breakage of the gate insulation film.

Silicon carbide semiconductor device and method for producing the same

A silicon carbide semiconductor device includes: a substrate; a drift layer; a current dispersion layer; a base region; a source region; trenches; a gate insulation film; a gate electrode; a source electrode; a drain electrode; and a bottom layer. The current dispersion layer is arranged on the drift layer, and has a first conductive type with an impurity concentration higher than the drift layer. The bottom layer has a second conductive type, is arranged under the base region, covers a bottom of each trench including a corner portion of the bottom of the trench, and has a depth equal to or deeper than the current dispersion layer.

Silicon carbide semiconductor device

A silicon carbide semiconductor device includes: a vertical MOSFET having: a semiconductor substrate including a high-concentration impurity layer and a drift layer; a base region; a source region; a trench gate structure; a source electrode; and a drain electrode. The base region has a high-concentration base region and a low-concentration base region having a second conductivity type with an impurity concentration lower than the high-concentration base region, which are stacked each other. Each of the high-concentration base region and the low-concentration base region contacts a side surface of the trench.

Silicon carbide semiconductor device and method for manufacturing same

A semiconductor device has a semiconductor substrate including a body region, a drift region, a trench that extends from a surface of the semiconductor substrate into the drift region through the body region, and a source region located adjacent to the trench in a range exposed to the surface of the semiconductor substrate, the source region being isolated from the drift region by the body region. A specific layer is disposed on a bottom of the trench, and it has a characteristic of forming a depletion layer at a junction between the specific layer and the drift region. An insulating layer covers an upper surface of the specific layer and a sidewall of the trench. A conductive portion is formed on a part of the side wall of the trench. The conductive portion is joined to the specific layer, and reaches the surface of the semiconductor substrate.

Semiconductor device having vertical MOSFET structure that utilizes a trench-type gate electrode and method of producing the same

The present application relates to technology for improving a withstand voltage of a semiconductor device. The semiconductor device includes a termination area that surrounds a cell area. The cell area is provided with a plurality of main trenches. The termination area is provided with one or more termination trenches surrounding the cell area. A termination trench is disposed at an innermost circumference of one or more termination trenches. A body region is disposed on a surface of a drift region. Each main trench reaches the drift region. A gate electrode is provided within each main trench. The termination trench reaches the drift region. Sidewalls and a bottom surface of the termination trench are covered with a insulating layer. A surface of the insulating layer covering the bottom surface of the termination trench is covered with a buried electrode. A gate potential is applied to the buried electrode.

Semiconductor device and method for manufacturing semiconductor device

A semiconductor device includes a silicon carbide semiconductor substrate, a transistor formed in a cell region of the semiconductor substrate, and a voltage-breakdown-resistant structure formed in a region which surrounds an outer periphery of the cell region. The semiconductor substrate includes a first conductivity type substrate, a first conductivity type drift layer on the first conductivity type substrate, a second conductivity type layer on the drift layer, and a first conductivity type layer on the second conductivity type layer. The voltage-breakdown-resistant structure includes a first recess which surrounds the outer periphery of the cell region and reaches the drift layer, a trench located at a side surface of the recess on an inner periphery of the recess, and a second conductivity type buried layer buried in the trench to provide the side surface of the first recess.

Silicon carbide semiconductor device and method of manufacturing the same

The silicon carbide semiconductor device includes a substrate, a drift layer, a base region, a source region, a trench, a gate insulating layer, a gate electrode, a source electrode, a drain electrode, and a deep layer. The deep layer is disposed under the base region and is located to a depth deeper than the trench. The deep layer is divided into a plurality of portions in a direction that crosses a longitudinal direction of the trench. The portions include a group of portions disposed at positions corresponding to the trench and arranged at equal intervals in the longitudinal direction of the trench. The group of portions surrounds corners of a bottom of the trench.

A semiconductor device includes a semiconductor substrate and an electric field terminal part. The semiconductor substrate includes a substrate, a drift layer disposed on a surface of the substrate, and a base layer disposed on a surface of the drift layer. The semiconductor substrate is divided into a cell region in which a semiconductor element is disposed and a peripheral region that surrounds the cell region. The base region has a bottom face located on a same plane throughout the cell region and the peripheral region and provides an electric field relaxing layer located in the peripheral region. The electric field terminal part surrounds the cell region and a portion of the electric field relaxing layer and penetrates the electric field relaxing layer from a surface of the electric field relaxing layer to the drift layer.

Semiconductor device including cell region and peripheral region having high breakdown voltage structure

A silicon carbide semiconductor device includes a substrate, a drift layer located on a first surface of the substrate, a base region located on the drift layer, a source region located on the base region, a trench penetrating the source region and the base region to the drift layer, a channel layer located in the trench, a gate insulating layer located on the channel layer, a gate electrode located on the gate insulating layer, a source electrode electrically coupled with the source region and the base region, a drain electrode located on a second surface of the substrate, and a deep layer. The deep layer is located under the base region, extends to a depth deeper than the trench and is formed along an approximately normal direction to a sidewall of the trench.

Silicon carbide semiconductor device including deep layer

The silicon carbide semiconductor device includes a trench formed from a surface of a drift layer of a first conductivity type formed on a substrate of the first conductivity type, and a deep layer of a second conductivity type located at a position in the drift layer beneath the bottom portion of the trench. The deep layer is formed at a certain distance from base regions of the second conductivity type formed on the drift layer so as to have a width wider than the width of the bottom portion of the trench, and surround both the corner portions of the bottom portion of the trench.

Silicon carbide semiconductor device, and method of manufacturing the same

An SiC semiconductor device includes a substrate, a drift layer disposed on a first surface of the substrate, a base region disposed above the drift layer, a source region disposed above the base region, a trench penetrating the source region and the base region to the drift layer, a gate insulating layer disposed on a surface of the trench, a gate electrode disposed on a surface of the gate insulating layer, a first electrode electrically coupled with the source region and the base region, a second electrode disposed on the second surface of the substrate, and a second conductivity-type layer disposed at a portion of the base region located under the source region. The second conductivity-type layer has the second conductivity type and has an impurity concentration higher than the base region.

A SiC semiconductor device includes: a substrate; a drift layer on the substrate; a trench on the drift layer; a base region in the drift layer sandwiching the trench; a channel between the base region and the trench; a source region in the base region sandwiching the trench via the channel; a gate electrode in the trench via a gate insulation film; a source electrode coupled with the source region; a drain electrode on the substrate opposite to the drift layer; and a bottom layer under the trench. An edge portion of the bottom layer under a corner of a bottom of the trench is deeper than a center portion of the bottom layer under a center portion of the bottom of the trench.

SiC semiconductor device having bottom layer and method for manufacturing the same

An SiC semiconductor device is provided, which comprises: a substrate made of silicon carbide and having a principal surface; a drift layer made of silicon carbide and disposed on the principal surface; an insulating layer disposed on the drift layer and including an opening; a Schottky electrode contacting with the drift layer through the opening; a termination structure disposed around an outer periphery of the opening; and second conductivity type layers disposed in a surface part of the drift layer, contacting the Schottky electrode, surrounded by the termination structure, and separated from one another. The second conductivity type layers include a center member and ring members. Each ring member surrounds the center member and is arranged substantially in a point symmetric manner with respect to the center member.

Silcon carbide semiconductor device having schottky barrier diode and method for manufacturing the same

An SiC semiconductor device and a related manufacturing method are disclosed having a structure provided with a p-type deep layer formed in a depth equal to or greater than that of a trench to cause a depletion layer between at a PN junction between the p-type deep layer and an n-type drift layer to extend into the n-type drift layer in a remarkable length, making it difficult for a high voltage, resulting from an adverse affect arising from a drain voltage, to enter a gate oxide film. This results in a capability of minimizing an electric field concentration in the gate oxide film, i.e., an electric field concentration occurring at the gate oxide film at a bottom wall of the trench.

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Anjo, Japan

Naohiro Suzuki