MOS type semiconductor device having a high ON current/OFF current ratio

Claim 2

A MOS type semiconductor device comprising: a first thin-film semiconductor having a drain region, a source region, and a channel region arranged between said drain and source region; a gate oxide film formed adjacent to said thin-film semiconductor; a gate formed in correspondence with said channel region via said gate oxide film; and a region, where no impurity is ion-implanted, formed at least between and drain region and said channel region corresponding to an end portion of said gate along a conductive channel direction, wherein said first thin-film semiconductor is formed such that a film thickness of said drain region, and said source region is made smaller than a film thickness of said channel region and is formed on a silicon substrate via an insulating film.

Claim 3

A device according to claim 1, wherein said MOS type semiconductor device is of a top gate type in which said first thin film semiconductor, said gate oxide film, and said gate are stacked in this order on said insulating film.

Claim 4

A device according to claim 1, wherein said MOS type semiconductor device is of a bottom gate type in which said gate, said gate oxide film, and said first thin-film semiconductor are stacked in this order on said insulating film.

Claim 5

A device according to claim 1, wherein said first thin-film semiconductor, said gate oxide film, said gate and a second thin-film semiconductor, which is insulated from said gate, is in contact with said first thin-film semiconductor, and has a large grain size, are stacked in this order on the insulating film.

Claim 6

A MOS type semiconductor device comprising: a first thin-film semiconductor having a drain region, a source region, and a channel region arranged between said drain region and said source region; a gate oxide film formed adjacent to said first thin-film semiconductor; a gate formed in correspondence with said channel region via said gate oxide film; and a region, where no impurity is ion-implanted, formed at least between said drain region and said channel region corresponding to an end portion of said gate along a conductive channel direction, wherein said first thin-film semiconductor is formed such that a film thickness of said drain region, and said source region is made smaller than a film thickness of said channel region and is a polycrystalline silicon thin film having a large grain size.

Claim 7

A MOS type semiconductor device comprising: a first thin-film semiconductor having a drain region, a source region, and a channel region arranged between said drain region and said source region; a gate oxide film formed adjacent to said first thin-film semiconductor; a gate formed in correspondence with said channel region via said gate oxide film; and a region, where no impurity is ion-implanted, formed at least between said drain region and said channel region corresponding to an end portion of said gate along a conductive channel direction, wherein said first thin-film semiconductor is formed such that a film thickness of said drain region, and said source region is made smaller than a film thickness of said channel region and is a polycrystalline silicon thin film having a large grain size.

Claim 8

A MOS type semiconductor device comprising: thin-film semiconductor having a drain region, a source region, and a channel region arranged between said drain region and said source region; a gate oxide film formed adjacent to said first thin-film semiconductor; a gate formed in correspondence with said channel region via said gate oxide film; and a non-implanted region, where no impurity is ion-implanted in said thin film semiconductor, formed at least between said drain region and said channel region corresponding to an end portion of said gate along a conductive channel direction wherein a film thickness of said drain region, said source region, and said non-implanted region is made smaller than a film thickness of said channel region.

Claim 9

A MOS type semiconductor device comprising: thin-film semiconductor having a drain region, a source region, and a channel region arranged between said drain region and said source region; a gate oxide film formed adjacent to said first thin-film semiconductor; a gate formed in correspondence with said channel region via said gate oxide film; and a non-implanted region, where no impurity is ion-implanted in said thin film semiconductor, formed at least between said drain region and said channel region corresponding to an end portion of said gate along a conductive channel direction wherein a film thickness of said drain region, said source region, and said non-implanted region is made smaller than a film thickness of said channel region.