Kabushiki Kaisha Toshiba

Bungo Tanaka

Tomoko Matsudai

Nobuyuki Sato

Kazuya Nakayama

Yoshitaka Hokomoto

Tatsuo Yoneda

Akio Takano

Tsuneo Ogura

Norio Yasuhara

Keiko Kawamura

Masatoshi Arai

Yuichi Oshino

Takeru Matsuoka

Tsuyoshi Ohta

Shunsuke Katoh

Yuuichi Oshino

Shunsuke Nitta

Shinya Ozawa

According to an embodiment, a semiconductor device includes a semiconductor layer, a first electrode, and a first insulating film. The first electrode extends in a first direction and is provided inside the semiconductor layer. The first insulating film is provided between the semiconductor layer and the first electrode, a thickness of the first insulating film in a direction from the first electrode toward the semiconductor layer increasing in stages along the first direction. The first insulating film has three or more mutually-different thicknesses.

Semiconductor device

The semiconductor device according to an aspect of the present invention includes: a semiconductor substrate of a first conductive type; a first semiconductor layer of the first conductive type formed on the main surface of the semiconductor substrate, the impurity concentration of the first semiconductor layer being lower than that of the semiconductor substrate; a second and third semiconductor layers of a second conductive type formed on the first semiconductor layer, the second and third semiconductor layers being isolated from each other; a first and second MOS transistors MOSand MOSof the first conductive type formed in the second and third semiconductor layers, the first semiconductor layer and the semiconductor substrate serving as drains of the first and second MOS transistors; and a conductive layer.

MOS semiconductor device

A semiconductor includes a first electrode, a first semiconductor region, a second semiconductor region, a third semiconductor region, and a gate electrode. The gate electrode has a first portion arranged with the second semiconductor region in a direction perpendicular to a first direction extending from the first electrode to the first semiconductor region, and has a second portion on the first portion. The semiconductor also includes a gate insulating layer between the gate electrode and each of the three semiconductor regions. The gate insulating layer extends to the upper surface of the third semiconductor region to form an extending portion. The second portion of the gate electrode protrudes in an upward direction from the upper surface of the extending portion of the gate insulating layer, and a lower part of the second portion of the gate electrode is embedded in the first portion of the gate electrode.

Semiconductor device and method of manufacturing semiconductor device

A semiconductor device includes a first semiconductor region of a first conductivity type, a second semiconductor region having a second conductivity type, a first insulating layer on the first and second semiconductor regions, and field plate electrodes are provided in the first insulating layer at different distances from the first semiconductor layer. A first field plate electrode is at a first distance, a second field plate electrode is at a second distance greater than the first distance, and a third field plate electrode is at a distance greater than the second distance. The first through third field plate electrodes are electrically connected to each other and the third electrode is electrically connected to the second semiconductor region.

A semiconductor device includes first electrode, first semiconductor layer of first conductivity type on the first electrode, second semiconductor layer of second conductivity type on the first semiconductor layer, third semiconductor layer of the first conductivity type on second semiconductor layer, fourth semiconductor layer of the second conductivity type selectively located on the third semiconductor layer, gate electrode through the third and fourth semiconductor layers and into the second semiconductor layer and insulated therefrom, second electrode on the fourth semiconductor layer, fifth semiconductor layer of the second conductivity type between the first electrode and the second semiconductor layer, sixth semiconductor layer of the first conductivity type on the second semiconductor layer contacting the second electrode, and seventh semiconductor layer of the first conductivity type in the second and sixth semiconductor layers, such that the bottom thereof is closer to the first electrode than the bottom of the gate insulating film.

According to one embodiment, a semiconductor device includes a first semiconductor layer, a second semiconductor layer provided in a portion on the first semiconductor layer, a first insulating layer provided on the first semiconductor layer on a terminal region side of the second semiconductor layer, a third semiconductor layer provided on the first semiconductor layer on the terminal region side of the first insulating layer, a second insulating layer provided on the first semiconductor layer on the terminal region side of the third semiconductor layer, a fourth semiconductor layer provided between the first semiconductor layer and the second insulating layer, and a plurality of field plate electrodes provided inside an inter-layer insulating film, the plurality of field plate electrodes having mutually-different distances from the first semiconductor layer.

A semiconductor device comprises on a surface of a first semiconductor layer of the first conduction type a second semiconductor layer of the first conduction type. A semiconductor base layer of the second conduction type is formed on the second semiconductor layer, and a semiconductor diffusion layer of the first conduction type is formed on a surface of the semiconductor base layer. A trench is formed from the surface of the semiconductor diffusion layer to a depth reaching the second semiconductor layer. A gate electrode is formed of a conductor film buried in the trench with a gate insulator interposed therebetween. The conductor film includes a first conductor film formed along the gate electrode to have a recess and a second conductor film formed to fill the recess.

Trench-gate MOS transistor composed of multiple conductors

A semiconductor device comprises a semiconductor substrate having an upper surface and a lower surface. A semiconductor layer is formed on the upper surface of the semiconductor substrate. A base region of a first conduction type is formed in the semiconductor layer. A source region of a second conduction type is formed in the base region. A drain region of the second conduction type is formed apart from the source region in the semiconductor layer. A gate electrode is formed on a gate insulator above the semiconductor layer between the source region and the drain region. A first interlayer insulator is formed on the semiconductor layer to cover the gate electrode. A short electrode is formed to short the base region and the source region. A second interlayer insulator is formed to cover the first interlayer insulator and the short electrode. A drain electrode is formed over the second interlayer insulator and connected to the drain region with the use of a contact hole formed through the first and second interlayer insulators. A source electrode is formed on the lower surface of the semiconductor substrate. The short electrode extends over the first interlayer insulator from the source region toward the drain region. A side of the short electrode at least coincides with a side of the gate electrode located toward the drain region with respect to positions in a direction defined as directing from the source region toward the drain region.

In a semiconductor layer of the first conductivity type, a first diffusion region of the second conductivity type is formed which includes a low resistance layer and a high resistance layer. This semiconductor layer of the first conductivity type has its thickness that is less than or equal to the lateral width of the high resistance layer.

A semiconductor device comprises a semiconductor substrate, a semiconductor layer formed above the semiconductor substrate, a plurality of unit cells each having a structure with a gate electrode disposed and formed above the semiconductor layer to have a stripe-like shape and with a source layer and a drain layer formed in the semiconductor layer to have stripe-like shapes respectively, a gate wiring line for mutually connecting together respective gate electrodes of the unit cells, a first main electrode being formed on a dielectric film covering the gate electrodes and the gate wiring line and being in contact with any one of the source layer and the drain layer of each unit cell, an impurity diffusion layer formed in the semiconductor layer to a depth reaching the semiconductor substrate only at part immediately underlying the gate wiring line, the part being selected from part immediately underlying a remaining one of the source layer and the drain layer of each unit cell and part immediately underlying the gate wiring line, the impurity diffusion layer being for permitting extension of the remaining one of the source and drain layers of each unit cell up to the semiconductor substrate, and a second main electrode as formed at a back surface of the semiconductor substrate.

Semiconductor device and method of fabricating the same

The semiconductor device according to an aspect of the present invention includes: a semiconductor substrate of a first conductive type; a first semiconductor layer of the first conductive type formed on the main surface of the semiconductor substrate, the impurity concentration of the first semiconductor layer being lower than that of the semiconductor substrate; a second and third semiconductor layers of a second conductive type formed on the first semiconductor layer, the second and third semiconductor layers being isolated from each other; a first and second MOS transistors MOS and MOS of the first conductive type formed in the second and third semiconductor layers, the first semiconductor layer and the semiconductor substrate serving as drains of the first and second MOS transistors; and a conductive layer.

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Yokohama, Japan

Bungo Tanaka