Semiconductor device and method for forming the same

A method for forming a semiconductor device comprising the steps of:

• forming a semiconductor film over a substrate, said semiconductor film having a portion to become an active layer of said semiconductor device;
• providing said semiconductor film with a metal containing material for promoting crystallization of said semiconductor film;
• crystallizing said semiconductor film with said metal containing material wherein said metal diffuses through said portion during the crystallization;
• patterning the crystallized film into said active layer;
• forming a gate insulating film comprising silicon oxide on the active layer;
• nitriding only in the vicinity of a surface of said gate insulating film;
• and
• forming a gate electrode on said gate insulating film,
• wherein said gate insulating film is doped with a gettering material.

A method for forming a semiconductor device comprising the steps of:

• forming a semiconductor film over a substrate, said semiconductor film having a portion to become an active layer of said semiconductor device;
• providing said semiconductor film with a metal containing material;
• crystallizing said semiconductor film wherein said metal diffuses through said portion during the crystallization;
• forming a gate insulating film comprising silicon oxide on the crystallized semiconductor film by chemical vapor deposition;
• nitriding only in the vicinity of a surface of said gate insulating film;
• and
• forming a gate electrode on said gate insulating film,
• wherein said gate insulating film is deposited with chlorine.

A method for forming a semiconductor device comprising the steps of:

• forming a semiconductor film over a substrate;
• providing said semiconductor film with a metal containing material for promoting crystallization of said semiconductor film;
• crystallizing said semiconductor film wherein said metal diffuses through the semiconductor film during the crystallization;
• forming an insulating film comprising silicon oxide on the crystallized semiconductor film by chemical vapor deposition wherein a gettering material is added into said insulating film;
• and
• nitriding only in a vicinity of a surface of said insulating film.

A method for forming a semiconductor device comprising the steps of:

• preparing a crystalline semiconductor film comprising silicon;
• forming a gate insulating film comprising silicon oxide over said crystalline semiconductor film;
• introducing a nitrogen element into said gate insulating film for nitriding only the vicinity of a surface thereof;
• and
• forming a gate electrode on said gate insulating film.

A method for forming a semiconductor device comprising the steps of:

• preparing a crystalline semiconductor film comprising silicon;
• forming a silicon oxide film over said crystalline semiconductor film;
• forming a silicon oxynitride film by nitriding only the vicinity of a surface of said silicon oxide film, and
• forming a gate electrode on said silicon oxynitride film.

A method for forming a semiconductor device comprising the steps of:

• preparing a crystalline semiconductor film comprising silicon;
• forming a gate insulating film comprising silicon oxide over said crystalline semiconductor film;
• nitriding only the vicinity of a surface of said gate insulating film, and
• forming a gate electrode on said gate insulating film,
• wherein said gate insulating film contains halogen element.

A method for forming a semiconductor device comprising the steps of:

• preparing a crystalline semiconductor film comprising silicon;
• forming a gate insulating film comprising silicon oxide over said crystalline semiconductor film;
• introducing a nitrogen element into said gate insulating film for nitriding only the vicinity of a surface thereof, and
• forming a gate electrode on said gate insulating film,
• wherein said gate insulating film contains halogen element.

A method for forming a semiconductor device comprising the steps of:

• preparing a crystalline semiconductor film comprising silicon;
• forming a silicon oxide film over said crystalline semiconductor film;
• forming a silicon oxynitride film by nitriding only the vicinity of a surface of said silicon oxide film, and
• forming a gate electrode on said silicon oxynitride film;
• wherein said gate insulating film contains halogen element.