Matsushita Electric Industrial Co., Ltd.

Matsushita Electronics Corporation

Seiji Sogo

Yoshihiro Mori

Yoshiaki Hachiya

Satoru Takahashi

Ryuma Hirano

Yuji Yamanishi

Seiki Yamaguchi

Yuji Ueno

The semiconductor device of the present invention includes: a semiconductor layer of a first conductivity type; source and drain regions of a second conductivity type, which are formed within the semiconductor layer; a channel region provided between the source and drain regions; and a gate electrode formed over the channel region. The device further includes: a buried region of the first conductivity type, at least part of the buried region being included in the drain region; and a heavily doped region of the second conductivity type. The heavily doped region is provided at least between a surface of the semiconductor layer and the buried region. The concentration of a dopant of the second conductivity type in the heavily doped region is higher than that of the dopant of the second conductivity type in the drain region.

Semiconductor device and method for fabricating the same

There is provided a method for fabricating a semiconductor device comprising a semiconductor layer of a first conductivity type, a source region of a second conductivity type formed within the semiconductor layer, a drain region of the second conductivity type formed within the semiconductor layer, a channel region provided between the source and drain regions, a gate electrode formed over the channel region, and a buried region of the first conductivity type having at least a part included in the drain region. The method for fabricating the semiconductor device comprises the steps of doping the semiconductor layer with a dopant of the second conductivity type for the drain region and doping the semiconductor layer with a dopant of the first conductivity type for the buried region. The step of doping the semiconductor layer with the dopant of the first conductivity type includes the steps of forming, on the semiconductor layer, a multilayer resist mask having an opening configured to correspond to the buried region and implanting dopant ions of the first conductivity type into the semiconductor layer via the multilayer resist mask by high-energy ion implantation.

An N.sup.- - region is formed by diffusion on a P- semiconductor substrate, and a P- region is formed in a surface portion of the N.sup.- - region. A P.sup.+ - region is formed in an outer peripheral portion of the N.sup.- - region, to suppress expansion of a depletion layer of the P- semiconductor substrate when a high voltage is applied. A gate oxide film is formed on the semiconductor substrate, and a gate electrode of polycrystalline silicon is formed on the gate oxide film, particularly on a channel region which is formed by the semiconductor substrate and the P.sup.+ - region, which is as a whole the same as a structure of a lateral N-channel MOSFET. Circuit elements are formed within the N.sup.- - region, and a high voltage is applied. Circuit portions are isolated as the gate electrode and a source region are grounded. This reduces the number of steps for manufacturing a high-insulation IC, increases a breakdown voltage, and integrates the circuit denser.

High voltage semiconductor device

Growing community of inventors

Kyoto, Japan

Seiji Sogo