Method for forming a multilayer integrated circuit

Claim 1

A method for forming a semiconductor device comprising the steps of: forming a first MOS transistor of one conductivity type on a semiconductor substrate; forming an insulating film on said first MOS transistor; selectively forming a semiconductor film on said insulating film; forming an opening in said insulating film; forming a gate electrode on said semiconductor film; oxidizing a material of said gate electrode; introducing an impurity into said semiconductor film to form a doped region therein; and forming an electrode connecting said doped region with one of source and drain of said first MOS transistor, wherein said electrode is in contact with top and side surfaces of said doped region.

Claim 2

A method for forming a semiconductor device comprising the steps of: forming a first MOS transistor of one conductivity type on a semiconductor substrate; forming an insulating film on said first MOS transistor; selectively forming a semiconductor film on said insulating film; forming an opening in said insulating film; forming a gate electrode on said semiconductor film; oxidizing a material of said gate electrode; introducing an impurity into said semiconductor film to form a doped region therein; and forming an electrode connecting said doped region with one of source and drain of said first MOS transistor, wherein said electrode is in contact with top and side surfaces of said doped region.

Claim 6

A method for forming a semiconductor device comprising: a first MOS transistor of one conductivity type provided on a semiconductor substrate; and a second MOS transistor of a conductivity type different from said one conductivity type provided on said first MOS transistor with an insulating film therebetween, said second MOS transistor comprising a gate electrode and an oxide layer covering a surface of said gate electrode, said method comprising the steps of: forming a semiconductor layer on said insulating film; forming a gate insulating film on said semiconductor layer; introducing an impurity into said semiconductor layer to form a doped region therein; removing a portion of said gate insulating film to expose a portion of said doped region of said semiconductor layer with a portion of said semiconductor layer being unexposed under said gate electrode and said oxide layer; forming a hole in the exposed portion; and forming an electrode and a wiring connecting the exposed portion of said doped region with a terminal of said first MOS transistor through said hole, wherein said electrode and said wiring are in contact with top and side surfaces of said doped region.

Claim 7

A method for forming a semiconductor device comprising: a first MOS transistor of one conductivity type provided on a semiconductor substrate; and a second MOS transistor of a conductivity type different from said one conductivity type provided on said first MOS transistor with an insulating film therebetween, said second MOS transistor comprising a gate electrode and an oxide layer covering a surface of said gate electrode, said method comprising the steps of: forming a semiconductor layer on said insulating film; forming a gate insulating film on said semiconductor layer; introducing an impurity into said semiconductor layer to form a doped region therein; removing a portion of said gate insulating film to expose a portion of said doped region of said semiconductor layer with a portion of said semiconductor layer being unexposed under said gate electrode and said oxide layer; forming a hole in the exposed portion; and forming an electrode and a wiring connecting the exposed portion of said doped region with a terminal of said first MOS transistor through said hole, wherein said electrode and said wiring are in contact with top and side surfaces of said doped region.

Claim 13

A method for forming a semiconductor device comprising the steps of: forming a first MOS transistor of one conductivity type on a semiconductor substrate; forming an insulating film on said first MOS transistor; selectively forming a semiconductor film on said insulating film; forming an opening in said insulating film; forming a gate electrode on said semiconductor film; oxidizing a material of said gate electrode to form an oxidized surface of said gate electrode; introducing an impurity into said semiconductor film to form a doped region therein; and forming an electrode connecting said doped region with one of source and drain of said first MOS transistor, wherein said electrode is in contact with top and side surfaces of said doped region, and wherein said electrode crosses said gate electrode over the oxidized surface of said gate electrode.

Claim 14

A method for forming a semiconductor device comprising the steps of: forming a first MOS transistor of one conductivity type on a semiconductor substrate; forming an insulating film on said first MOS transistor; selectively forming a semiconductor film on said insulating film; forming an opening in said insulating film; forming a gate electrode on said semiconductor film; oxidizing a material of said gate electrode to form an oxidized surface of said gate electrode; introducing an impurity into said semiconductor film to form a doped region therein; and forming an electrode connecting said doped region with one of source and drain of said first MOS transistor, wherein said electrode is in contact with top and side surfaces of said doped region, and wherein said electrode crosses said gate electrode over the oxidized surface of said gate electrode.