Ricoh Company, Ltd.

Masato Kijima

Naohiro Ueda

Masaaki Yoshida

Atsushi Harikai

A semiconductor device has a configuration in which more than three kinds of wells are formed with small level differences. One kind of well from among the more than three kinds of wells has a surface level higher than other kinds of wells from among the more than three kinds of wells. The one kind of well is formed adjacent to and self-aligned to at least one kind of well from among the other kinds of wells. The other kinds of wells are different in one of a conductivity type, an impurity concentration and a junction depth, and include at least two kinds of wells having the same surface level.

Semiconductor device having a plurality of kinds of wells and manufacturing method thereof

A semiconductor device is disclosed that comprises a high breakdown voltage MOSFET. The MOSFET includes a source region of a second conductivity type and a drain region of the second conductivity type formed apart from each other in a well region of a first conductivity type, a channel region formed between the source region and the drain region, a gate insulation film formed on the channel region, a LOCOS oxide film having greater film thickness than the gate insulation film, and a gate electrode formed across the gate insulation film and the LOCOS oxide film.

Semiconductor device and method of manufacturing the same

A method is provided for forming plural kinds of wells on a single semiconductor substrate with an improved alignment accuracy and obviating the generation of step height between the wells. The method includes forming a selective etching film on the semiconductor substrate, forming openings on the selective etching film overlying a first well forming region and an alignment mark forming region using a first resist film as a mask for defining the first well forming region and the alignment mark forming region, implanting the first well forming region with a dopant of a first conductivity type and removing the first resist film, forming a second resist film to mask at least the first well forming region, having an opening overlying the alignment mark forming region larger than the opening of the selective etching film overlying the same region, and forming the alignment mark by performing an etching process using the second resist film and selective etching film as a mask.

Method for forming plural kinds of wells on a single semiconductor substrate

A semiconductor device is disclosed that comprises a high breakdown voltage MOSFET. The MOSFET includes a source region of a second conductivity type and a drain region of the second conductivity type formed apart from each other in a well region of a first conductivity type, a channel region formed between the source region and the drain region, a gate insulation film formed on the channel region, a LOCOS oxide film having a greater film thickness than the gate insulation film and formed adjacent to the gate insulation film, and a gate electrode formed across the gate insulation film and the LOCOS oxide film.

A method and system for determining a dry etching endpoint, at which a dry etching process should be terminated. The dry etching process is carried out in a plasma etching system and comprises the steps of detecting an intensity of light emission generated in the dry etching process, the light emission being extracted through a window located on a side wall portion of a reaction chamber below a horizontal plane which is defined by a surface of a body to be etch treated. The detected intensity is compared to a predetermined threshold level.

Growing community of inventors

Hyogo, Japan

Masato Kijima