Semiconductor device and method for fabricating the same

A thin film transistor comprising:

• a semiconductor film formed on an insulating surface;
• a channel region formed within said semiconductor film;
• source and drain regions comprising a metal silicide formed within said semiconductor film;
• high resistance regions formed within said semiconductor film between said channel region and said source and drain regions, said high resistance regions having a higher resistance than said source and drain regions;
• a gate insulating film formed on said semiconductor film;
• and
• a gate electrode formed on said gate insulating film,
• wherein side edges of said gate insulating film are aligned with boundaries between said high resistance regions and said source and drain regions.

A thin film transistor comprising:

• a semiconductor film formed on an insulating surface;
• a channel region formed within said semiconductor film;
• source and drain regions formed within said semiconductor film and containing an impurity for giving one conductivity type thereto;
• high resistance regions containing the same impurity as said source and drain regions, wherein said high resistance regions are formed within said semiconductor film between said channel region and said source and drain regions, said high resistance regions having a higher resistance than said source and drain regions;
• a gate insulating film formed on said semiconductor film;
• and
• a gate electrode formed on said gate insulating film,
• wherein side edges of said gate insulating film are aligned with boundaries between said high resistance regions and said source and drain regions, and a length of said high resistance regions is from 0.4 to 5 .mu.m, respectively.

A thin film transistor comprising:

• a semiconductor film formed on an insulating surface;
• a channel region formed within said semiconductor film;
• source and drain regions formed within said semiconductor film and containing an impurity for giving one conductivity type thereto;
• high resistance regions of which sheet resistance is 10 to 500 k.OMEGA./square formed within said semiconductor film between said channel region and said source and drain regions, said high resistance regions having a higher resistance than said source and drain regions;
• a gate insulating film formed on said semiconductor film;
• and
• a gate electrode formed on said gate insulating film,
• wherein side edges of said gate insulating film are aligned with boundaries between said high resistance regions and said source and drain regions.

A thin film transistor comprising:

• a semiconductor film formed on an insulating surface;
• a channel region formed within said semiconductor film;
• source and drain regions formed within said semiconductor film and containing an impurity for giving one conductivity type thereto;
• high resistance regions formed within said semiconductor film between said channel region and said source and drain regions, said high resistance regions having a higher resistance than said source and drain regions;
• a gate insulating film formed on said semiconductor film;
• a gate electrode formed on said gate insulating film;
• and
• an oxide film formed on at least side surfaces of said gate electrode,
• wherein side edges of said gate insulating film are aligned with boundaries between said high resistance regions and said source and drain regions, and said channel region extends beyond side edges of said gate electrode to form a pair of offset regions.

A thin film transistor comprising:

• a semiconductor film formed on an insulating surface;
• a channel region formed within said semiconductor film;
• a pair of metal silicide regions formed throughout a thickness of said semiconductor film;
• a pair of high resistance regions formed within said semiconductor film between said channel region and said pair of metal silicide regions, respectively, said high resistance regions having a higher resistance than said source and drain regions;
• a gate insulating film formed on said semiconductor film;
• and
• a gate electrode formed on said gate insulating film,
• wherein side edges of said gate insulating film are aligned with boundaries between said high resistance regions and said source and drain regions.

A thin film transistor comprising:

• a semiconductor film formed on an insulating surface;
• a channel region formed within said semiconductor film;
• source and drain regions formed within said semiconductor film and containing an impurity for giving one conductivity type thereto, wherein said source and drain regions comprises a metal silicide;
• high resistance regions formed within said semiconductor film between said channel region and said source and drain regions, said high resistance regions having a higher resistance than said source and drain regions and containing the same impurity as said source and drain regions, wherein a concentration of said impurity in said high resistance region is smaller than that in said source and drain regions;
• a gate insulating film formed on said semiconductor film;
• and
• a gate electrode formed on said gate insulating film,
• wherein side edges of said gate insulating film are aligned with boundaries between said high resistance regions and said source and drain regions.