Insulated gate type field effect device and method of making the same

Claim 1

A method of forming a semiconductor device comprising the steps of selectively forming a first insulating film on a surface of a semiconductor substrate, forming a thin semiconductor layer of low resistivity and of the same conductivity type as that of said substrate in the substrate over which said first insulating film was not formed, removing said first insulating film, forming a second insulating film on the whole surface of said substrate, selectively removing said second insulating film so as to make a first, a second and a third hole, said first and second holes exposing the substrate surface which was covered with said first insulating film, said third hole exposing the substrate surface wherein said semiconductor layer was formed, diffusing an impurity into the exposed substrate surface to form a first, a second and a third semiconductor region having an opposite conductivity type to that of said substrate through said first, second and third holes, respectively, removing selectively the portion of said second insulating film remaining on the substrate surface between said first and second regions, forming a third thin insulating film on the exposed portion of said substrate surface, and forming an interconnection layer ohmically contacting said third region and extending on said second and third insulating films.

Claim 2

A method of forming a semiconductor device comprising the steps of selectively forming a first insulating film on a surface of a semiconductor substrate, forming a thin semiconductor layer of low resistivity and of the same conductivity type as that of said substrate in the substrate over which said first insulating film was not formed, removing said first insulating film, forming a second insulating film on the whole surface of said substrate, selectively removing said second insulating film so as to make a first, a second and a third hole, said first and second holes exposing the substrate surface which was covered with said first insulating film, said third hole exposing the substrate surface wherein said semiconductor layer was formed, diffusing an impurity into the exposed substrate surface to form a first, a second and a third semiconductor region having an opposite conductivity type to that of said substrate through said first, second and third holes, respectively, removing selectively the portion of said second insulating film remaining on the substrate surface between said first and second regions, forming a third thin insulating film on the exposed portion of said substrate surface, and forming an interconnection layer ohmically contacting said third region and extending on said second and third insulating films.

Claim 3

A method of forming a semiconductor device comprising the steps of preparing a monocrystalline semiconductor substrate having one conductivity type; forming a thin semiconductor layer of low resistivity and of the same conductivity type as that of said substrate on the entire surface of said substrate; selectively forming an insulating film on the surface of said substrate; forming a source, a drain and a clamping diode region having an opposite conductivity type to that of said substrate in said substrate; etching all of said thin semiconductor layer between said source and drain regions; forming an interconnection layer ohmically contacting said clamping diode and extending over said insulating film; and forming a gate electrode over an insulating film portion between said source and drain regions, which is electrically connected with said interconnection layer.

Claim 4

A method of forming a semiconductor device comprising the steps of preparing a monocrystalline semiconductor substrate having one conductivity type; forming a thin semiconductor layer of low resistivity and of the same conductivity type as that of said substrate on the entire surface of said substrate; selectively forming an insulating film on the surface of said substrate; forming a source, a drain and a clamping diode region having an opposite conductivity type to that of said substrate in said substrate; etching all of said thin semiconductor layer between said source and drain regions; forming an interconnection layer ohmically contacting said clamping diode and extending over said insulating film; and forming a gate electrode over an insulating film portion between said source and drain regions, which is electrically connected with said interconnection layer.

Claim 6

A method of forming a semiconductor device comprising the steps of forming a thin semiconductor layer of low resistivity contiguous to a substrate of higher resistivity, said semiconductor layer and said substrate being of the same conductivity type, selectively forming several semiconductor regions of a conductivity type opposite to said first-mentioned conductivity type, in at least portions of said semiconductor layer to form PN junctions by using an insulating film as a mask, forming an interconnecting layer in ohmic contact with one of said regions and extending over an insulating film portion formed over said semiconductor layer, and forming a gate electrode over an insulating film portion between two further ones of said regions, which is electrically connected with said interconnecting layer.

Claim 7

A method of forming a semiconductor device comprising the steps of forming a thin semiconductor layer of low resistivity contiguous to a substrate of higher resistivity, said semiconductor layer and said substrate being of the same conductivity type, selectively forming several semiconductor regions of a conductivity type opposite to said first-mentioned conductivity type, in at least portions of said semiconductor layer to form PN junctions by using an insulating film as a mask, forming an interconnecting layer in ohmic contact with one of said regions and extending over an insulating film portion formed over said semiconductor layer, and forming a gate electrode over an insulating film portion between two further ones of said regions, which is electrically connected with said interconnecting layer.

Claim 8

A method of forming an insulated gate type field effect device comprising the steps of: forming a first, a second, a third, a fourth and a fifth region in a surface of a semiconductor substrate of one conductivity type, so that said first and second regions are of said one conductivity type and have a resistivity lower than that of the substrate, so that said third, fourth and fifth regions are of another conductivity type opposite to said one conductivity type, so that said third and fourth regions contact said first region and said fifth region contacts said second region, and so that a surface portion of the substrate is exposed between said fourth and fifth regions; forming an insulating film covering said regions and the surfaces of the substrate, and having a hole extending to said third region; and forming on said insulating film a conductive layer covering said surface portion of the substrate so as to bridge said fourth and fifth regions, and being connected to said third region through said hole.

Claim 9

A method of forming an insulated gate type field effect device comprising the steps of: forming a first, a second, a third, a fourth and a fifth region in a surface of a semiconductor substrate of one conductivity type, so that said first and second regions are of said one conductivity type and have a resistivity lower than that of the substrate, so that said third, fourth and fifth regions are of another conductivity type opposite to said one conductivity type, so that said third and fourth regions contact said first region and said fifth region contacts said second region, and so that a surface portion of the substrate is exposed between said fourth and fifth regions; forming an insulating film covering said regions and the surfaces of the substrate, and having a hole extending to said third region; and forming on said insulating film a conductive layer covering said surface portion of the substrate so as to bridge said fourth and fifth regions, and being connected to said third region through said hole.

Claim 10

A method of forming an insulated gate type field effect device comprising the steps of: selectively forming a first insulating film on a surface of a semiconductor substrate; forming first semiconductor regions of low resistivity and of the same conductivity type as that of said substrate in portions of the substrate over which said first insulating film is not formed; forming on the surfaces of said substrate and said first semiconductor regions a second insulating film having a first, a second and a third hole, said first and second holes exposing the substrate surfaces in which said first semiconductor regions were not formed and the surfaces of the adjoining first semiconductor regions, said third hole exposing the substrate surface wherein one of said first semiconductor regions is formed; introducing an impurity into the exposed surfaces to form a second, a third and a fourth semiconductor region having an opposite conductivity type with respect to that of said substrate through said first, second and third holes, respectively; selectively removing the portion of said second insulating film remaining on the substrate surface between said second and third regions, in which surface said first semiconductor region is not formed; forming a third thin insulating film on the exposed portion of said substrate surface; and forming an interconnection layer ohmically contacting said third region and extending on said second and third insulating films.

Claim 11

A method of forming an insulated gate type field effect device comprising the steps of: selectively forming a first insulating film on a surface of a semiconductor substrate; forming first semiconductor regions of low resistivity and of the same conductivity type as that of said substrate in portions of the substrate over which said first insulating film is not formed; forming on the surfaces of said substrate and said first semiconductor regions a second insulating film having a first, a second and a third hole, said first and second holes exposing the substrate surfaces in which said first semiconductor regions were not formed and the surfaces of the adjoining first semiconductor regions, said third hole exposing the substrate surface wherein one of said first semiconductor regions is formed; introducing an impurity into the exposed surfaces to form a second, a third and a fourth semiconductor region having an opposite conductivity type with respect to that of said substrate through said first, second and third holes, respectively; selectively removing the portion of said second insulating film remaining on the substrate surface between said second and third regions, in which surface said first semiconductor region is not formed; forming a third thin insulating film on the exposed portion of said substrate surface; and forming an interconnection layer ohmically contacting said third region and extending on said second and third insulating films.

Claim 12

A method of forming an insulated gate type field effect device comprising the steps of : providing a semiconductor substrate of a first conductivity type; forming in a first and second selected surface portions of said substrate, first and second semiconductor regions of said first conductivity type but of a resistivity lower than that of said substrate; forming, in third, fourth and fifth selected surface portions of said substrate, third, fourth and fifth semiconductor regions of a second conductivity type opposite said first conductivity type, said third and fourth surface portions contacting said first surface portion so that said third and fourth regions contact said first region, and said fifth surface portion contacting said second surface portion but being spaced apart from said fourth surface portion by an exposed sixth surface portion of said substrate so that said fifth region contacts said second region; selectively forming an insulating film on the surfaces of said regions except for a selected area of said third region; and forming a conductive layer on said selected area of said third region and over a selected portion of said insulating film, which selected portion of said film extends from said third region over said first and fourth regions to said sixth region.

Claim 13

A method of forming an insulated gate type field effect device comprising the steps of : providing a semiconductor substrate of a first conductivity type; forming in a first and second selected surface portions of said substrate, first and second semiconductor regions of said first conductivity type but of a resistivity lower than that of said substrate; forming, in third, fourth and fifth selected surface portions of said substrate, third, fourth and fifth semiconductor regions of a second conductivity type opposite said first conductivity type, said third and fourth surface portions contacting said first surface portion so that said third and fourth regions contact said first region, and said fifth surface portion contacting said second surface portion but being spaced apart from said fourth surface portion by an exposed sixth surface portion of said substrate so that said fifth region contacts said second region; selectively forming an insulating film on the surfaces of said regions except for a selected area of said third region; and forming a conductive layer on said selected area of said third region and over a selected portion of said insulating film, which selected portion of said film extends from said third region over said first and fourth regions to said sixth region.