Semiconductor devices constitute constant voltage devices used to raise internal voltage

A semiconductor device comprising:

• a high-concentration doped layer, a low-concentration doped layer having a conductivity type different than said high-concentration doped layer, and an isolating insulator film, wherein said high-concentration doped layer is directly connected to said low-concentration doped layer and not directly connected to said isolating insulator film.

A method for manufacturing a semiconductor device comprising the steps of:

• forming an isolating insulator film in a semiconductor substrate so that said isolating insulator film is connected to an active region, forming a high-concentration doped layer in the active region, and forming a low-concentration doped layer having a conductivity type different than said high-concentration doped layer so that said low-concentration doped layer is connected to said high-concentration doped layer in the active region, wherein the step of forming a low-concentration doped layer includes forming a first portion of said low-concentration doped layer adjacent said isolating insulator film, the first portion having an ion concentration lower than another portion of said low-concentration doped layer.

A method for manufacturing a semiconductor device comprising the steps of:

• forming an isolating insulator film in a semiconductor substrate, forming a high-concentration doped layer in the semiconductor substrate in such a manner that said high-concentration doped layer is not directly connected to said isolating insulator film, and forming a low-concentration doped layer having a conductivity type different than said high-concentration doped layer in the semiconductor substrate so that low-concentration doped layer is directly connected to said high-concentration doped layer.