Rohm Co., Ltd.

Naoki Izumi

Tomoyasu Sada

Yoshikazu Nakagawa

Masaki Nagata

A semiconductor device includes a semiconductor layer. A first conductivity type region is formed on a base layer portion of the semiconductor layer. A body region of a second conductivity type is formed on the semiconductor layer to be in contact with the first conductivity type region. A trench in which a gate electrode is embedded through a gate insulating film is formed on the semiconductor layer. The trench penetrates through the body region, so that a deepest portion thereof reaches the first conductivity type region. A source region of the first conductivity type is formed on a surface layer portion of the semiconductor layer around the trench. The gate insulating film includes a thick-film portion having a relatively large thickness on a bottom surface of the trench.

Semiconductor device and method of manufacturing semiconductor device

A semiconductor device according to the present invention includes: an insulating layer; a semiconductor layer of a first conductive type laminated on the insulating layer; an annular deep trench having a thickness reaching the insulating layer from a top surface of the semiconductor layer; a body region of a second conductive type formed across an entire thickness of the semiconductor layer along a side surface of the deep trench in an element forming region surrounded by the deep trench; a drift region of the first conductive type constituted of a remainder region besides the body region in the element forming region; a source region of the first conductive type formed in a top layer portion of the body region; a drain region of the first conductive type formed in a top layer portion of the drift region; and a first conductive type region formed in the drift region, having a deepest portion reaching a position deeper than the drain region, and having a first conductive type impurity concentration higher than the first conductive type impurity concentration of the semiconductor layer and lower than the first conductive type impurity concentration of the drain region.

Semiconductor device

A semiconductor device according to the present invention includes a semiconductor layer. A first conductivity type region is formed on a base layer portion of the semiconductor layer. A body region of a second conductivity type is formed on the semiconductor layer to be in contact with the first conductivity type region. A trench in which a gate electrode is embedded through a gate insulating film is formed on the semiconductor layer. The trench penetrates through the body region, so that a deepest portion thereof reaches the first conductivity type region. A source region of the first conductivity type is formed on a surface layer portion of the semiconductor layer around the trench. The gate insulating film includes a thick-film portion having a relatively large thickness on a bottom surface of the trench.

A method of manufacturing a semiconductor device having a VDMOSFET (Vertical Double-diffused Metal Oxide Semiconductor Field-Effect Transistor) and a planar gate MOSFET (Metal Oxide Semiconductor Field-Effect Transistor), including forming a semiconductor layer of a first conductivity type by epitaxy, forming a body region recess for forming a body region of the VDMOSFET on the semiconductor layer, and embedding a semiconductor material of a second conductivity type in the body region recess by epitaxy or CVD (Chemical Vapor Deposition).

Lateral double diffused MOSFET device

A semiconductor device includes a semiconductor layer with a trench dug downward from its surface, a source region formed on a surface layer portion adjacent to a first side of the trench in a prescribed direction, a drain region formed on the surface layer portion, adjacent to a second side of the trench opposite to the first side in the prescribed direction, a first insulating film on the bottom surface and the side surface of the trench, a floating gate stacked on the first insulating film and opposed to the bottom surface and the side surface of the trench through the first insulating film, a second insulating film formed on the floating gate, and a control gate at least partially embedded in the trench so that the portion embedded in the trench is opposed to the floating gate through the second insulating film.

Semiconductor device including a floating gate

A semiconductor device according to the present invention includes: a body region of a first conductive type; trenches formed by digging in from a top surface of the body region; gate electrodes embedded in the trenches; source regions of a second conductive type formed at sides of the trenches in a top layer portion of the body region; and body contact regions of the first conductive type, penetrating through the source regions in a thickness direction and contacting the body region. The body contact regions are formed in a zigzag alignment in a plan view. With respect to a column formed by the body contact regions aligned in a predetermined column direction, the trenches are disposed at both sides in a row direction orthogonal to the column direction in a plan view, extend in the column direction, and form meandering lines each connecting a plurality of curved portions so that a predetermined gap in the row direction is formed respectively between adjacent trenches extending in the column direction and between the trenches and the body contact regions.

A semiconductor device according to the present invention includes: a semiconductor layer of a first conductivity type; a body region of a second conductivity type formed in a surface layer portion of the semiconductor layer; a trench dug from the surface of the semiconductor layer to penetrate the body region; a source region of a first conductivity type formed on a side portion of the trench in a surface layer portion of the body region; a gate insulating film formed on the bottom surface and the side surface of the trench; a gate electrode embedded in the trench through the gate insulating film and so formed that the surface thereof is lower by one stage than the surface of the source region; and a peripheral wall film formed on a peripheral edge portion of the surface of the gate electrode to be opposed to an upper end portion of the side surface of the trench.

A semiconductor device includes a first conductivity type layer of a first conductivity type, a body layer of a second conductivity type formed on the first conductivity type layer, a gate trench passing through the body layer so that the deepest portion thereof reaches the first conductivity type layer, a source region of the first conductivity type formed around the gate trench on the surface layer portion of the body layer, a gate insulating film formed on the bottom surface and the side surface of the gate trench, and a gate electrode embedded in the gate trench through the gate insulating film, and the bottom surface of the gate electrode and the upper surface of the first conductivity type layer are flush with each other.

Semiconductor device having trench gate VDMOSFET and method of manufacturing the same

A semiconductor device according to an aspect of the present invention includes a semiconductor layer, an insulating film formed on the surface of the semiconductor layer, a first insulator embedded in the semiconductor layer with a thickness larger than the thickness of the insulating film, and a resistive element formed on the first insulator. A semiconductor device according to another aspect of the present invention includes a semiconductor layer, an insulating film formed on the surface of the semiconductor layer, a resistive element formed on the insulating film, and a floating region formed on a portion of the semiconductor layer opposed to the resistive element through the insulating film and electrically floating from a periphery thereof.

Growing community of inventors

Kyoto, Japan

Naoki Izumi