Integrated insulated gate field effect transistors with thin insulation region between field insulation regions

Abstract

Disclosed is a semiconductor device, which has: a first device-separating insulating film which is formed on a semiconductor substrate and extends in a first(Y) direction; a second device-separating insulting film which is formed on said semiconductor substrate and extends in a second(X) direction normal to the first(Y) direction; a first-conductivity-type device region which is formed on the semiconductor substrate and is sectioned by the first and second device-separating insulating films; and a first first-conductive-type high concentration impurity layer which is formed under the first device-separating insulating film and extends in the first(Y) direction; wherein the second device-separating insulating film is connected with the first device-separating insulating film through an insulating film thinner than both the first and second device-separating insulating films, the thin insulating film extending over the first high concentration impurity layer to separate the device region arranged in the second(X) direction from each other by the first device-separating insulating film and the first high concentration impurity layer, and the device region arranged in the first(Y) direction is separated by the second device-separating insulating film and the thin insulating film.

Dependencies are inferred from the claim text.