Semiconductor integrated circuit and method for forming the same

A semiconductor device comprising an n-channel type thin film transistor and a p-channel type thin film transistor, each comprising:

• a semiconductor film formed over a substrate having an insulating surface;
• a pair of source and drain regions in said semiconductor film;
• a channel region in said semiconductor film;
• and
• a gate insulating film adjacent to said channel region and a gate electrode adjacent to said channel region with said gate insulating film interposed therebetween,
• wherein said n-channel type thin film transistor has at least one lightly doped region between said channel region and at least one of said source and drain regions,
• wherein said p-channel type thin film transistor has no lightly doped region between said channel region and either of said source and drain regions in said semiconductor film, and said source and drain regions are doped with both phosphorus and boron, and
• wherein said lightly doped region has a dose amount between 1×1013 and 5×1014 atoms/cm.

A semiconductor device comprising an n-channel type thin film transistor and a p-channel type thin film transistor, each comprising:

• a semiconductor film formed over a substrate having an insulating surface;
• a gate insulating film formed on said semiconductor film;
• a pair of impurity regions formed in said semiconductor film;
• a channel region formed in said semiconductor film between said pair of impurity regions;
• a gate electrode formed over the channel region with said gate insulating film interposed therebetween;
• and
• a second insulating film comprising silicon nitride formed on said gate insulating film and said gate electrode,
• wherein said n-channel type thin film transistor has at least one lightly doped region disposed between said channel region and at least one of said pair of impurity regions, and said p-channel type thin film transistor has no lightly doped region between said channel region and either of said pair of impurity regions,
• wherein said gate insulating film and said second insulating film cover said semiconductor film except for contact holes opened therein, and
• wherein said lightly doped region has a dose amount between 1×1013 and 5×1014 atoms/cm2.

A semiconductor device comprising an n-channel type thin film transistor and a p-channel type thin film transistor, each comprising:

• a semiconductor film formed over a substrate having an insulating surface;
• a gate insulating film formed on said semiconductor film;
• a pair of impurity regions formed in said semiconductor film;
• a channel region formed in said semiconductor film between said pair of impurity regions;
• a gate electrode formed over the channel region with said gate insulating film interposed therebetween;
• and
• a second insulating film formed on said gate insulating film and said first and second gate electrodes,
• wherein said n-channel type thin film transistor has at least one lightly doped region disposed between said channel region and at least one of said pair of impurity regions, and said p-channel type thin film transistor has no lightly doped region between said channel region and either of said pair of impurity regions,
• wherein said gate insulating film and said second insulating film cover said semiconductor film except for contact holes opened therein, and
• wherein said lightly doped region has a dose amount between 1×1013 and 5×1014 atoms/cm2.

A semiconductor device having an active matrix circuit comprising a plurality of switching elements formed over a substrate for switching pixels;

• and a driver circuit for driving said active matrix circuit, said driver circuit comprising an n-channel type thin film transistor and a p-channel type thin film transistor, each comprising:
• a semiconductor film formed over said substrate having an insulating surface;
• a pair of source and drain regions in said semiconductor film;
• a channel region in said semiconductor film;
• and
• a gate insulating film adjacent to said channel region and a gate electrode adjacent to said channel region with said gate insulating film interposed therebetween,
• wherein said n-channel type thin film transistor has at least one lightly doped region between said channel region and at least one of said source and drain regions,
• wherein said p-channel type thin film transistor has no lightly doped region between said channel region and either of said source and drain regions in said semiconductor film, and
• wherein said lightly doped region has a dose amount between 1×1013 and 5×1014 atoms/cm2.

A semiconductor device having an active matrix circuit comprising a plurality of switching elements formed over a substrate for switching pixels;

• and a driver circuit for driving said active matrix circuit, said driver circuit comprising an n-channel type thin film transistor and a p-channel type thin film transistor, each comprising:
• a semiconductor film formed over said substrate having an insulating surface;
• a pair of source and drain regions in said semiconductor film;
• a channel region in said semiconductor film;
• and
• a gate insulating film adjacent to said channel region and a gate electrode adjacent to said channel region with said gate insulating film interposed therebetween,
• wherein said n-channel type thin film transistor has at least one lightly doped region between said channel region and at least one of said source and drain regions,
• wherein said p-channel type thin film transistor has no lightly doped region between said channel region and either of said source and drain regions in said semiconductor film, and said source and drain regions are doped with both phosphorus and boron, and
• wherein said lightly doped region has a dose amount between 1×1013 and 5×1014 atoms/cm2.

A semiconductor device having an active matrix circuit comprising a plurality of switching elements formed over a substrate for switching pixels;

• and a driver circuit for driving said active matrix circuit, said driver circuit comprising an n-channel type thin film transistor and a p-channel type thin film transistor, each comprising:
• a semiconductor film formed over said substrate having an insulating surface;
• a gate insulating film formed on said semiconductor films;
• a pair of impurity regions formed in said semiconductor film;
• a channel region formed in said semiconductor film between said pair of impurity regions;
• a gate electrode formed over the channel region with said gate insulating film interposed therebetween;
• and
• a second insulating film comprising silicon nitride formed on said gate insulating film and said gate electrode,
• wherein said n-channel type thin film transistor has at least one lightly doped region disposed between said channel region and at least one of said pair of impurity regions, and said p-channel type thin film transistor has no lightly doped region between said channel region and either of said pair of impurity regions,
• wherein said gate insulating film and said second insulating film cover said semiconductor film except for contact holes opened therein, and
• wherein said lightly doped region has a dose amount between 1×1013 and 5×1014 atoms/cm2.

A semiconductor device having an active matrix circuit comprising a plurality of switching elements formed over a substrate for switching pixels;

• and a driver circuit for driving said active matrix circuit, said driver circuit comprising an n-channel type thin film transistor and a p-channel type thin film transistor, each comprising:
• a semiconductor film formed over said substrate having an insulating surface;
• a gate insulating film formed on said semiconductor films;
• a pair of impurity regions formed in said semiconductor film;
• a channel region formed in said semiconductor film between said pair of impurity regions;
• a gate electrode formed over the channel region with said gate insulating film interposed therebetween;
• and
• a second insulating film formed on said gate insulating film and said gate electrode,
• wherein said n-channel type thin film transistor has at least one lightly doped region disposed between said channel region and at least one of said pair of impurity regions, and said p-channel type thin film transistor has no lightly doped region between said channel region and either of said pair of impurity regions,
• wherein said gate insulating film and said second insulating film cover said semiconductor film except for contact holes opened therein, and
• wherein said lightly doped region has a dose amount between 1×1013 and 5×1014 atoms/cm2.