Thin film semiconductor and method for manufacturing the same, semiconductor device and method for manufacturing the same

A method for manufacturing a semiconductor device having an active layer comprising the thin film semiconductor, said method comprising the steps of:

• forming a silicon oxide film by sputtering on the surface of a substrate having an insulating surface;
• intentionally forming at least a concave or convex pattern by patterning said silicon oxide film into a shape;
• forming an amorphous silicon film by low pressure thermal CVD on said silicon oxide film;
• forming a metallic element which accelerates the crystallization to the amorphous silicon film;
• crystallizing said amorphous silicon film into a crystalline silicon film by means of heat treatment;
• and
• irradiating a laser light or an intense light having an energy equivalent to that of said laser light to said crystalline silicon film, wherein:
• said crystalline silicon film is modified into a monodomain region by the step of irradiating a laser light or an intense light having an energy equivalent to that of said laser light;
• and
• said active layer is formed by using only said monodomain region.

A method for manufacturing a semiconductor device having an active layer comprising a thin film semiconductor, said method comprising the steps of:

• forming a silicon oxide film by sputtering on the surface of a substrate having an insulating surface;
• intentionally forming at least a concave or convex pattern by patterning said silicon oxide film into a shape;
• forming an amorphous silicon film by means of low pressure thermal CVD on said silicon oxide film;
• forming a metallic element which accelerates the crystallization to said amorphous silicon film;
• crystallizing said amorphous silicon film into a crystalline silicon film by heat treatment;
• modifying said crystalline silicon film into a monodomain region by irradiating a laser light or an intense light having an energy equivalent to that of said laser light to said crystalline silicon film;
• forming an active layer by using said monodomain region alone;
• forming an insulating film covering said active layer and containing silicon as a main component by vapor phase method;
• performing heat treatment in an atmosphere containing a halogen element for gettering and removing the metallic element which accelerates the crystallization and, at the same time, forming a thermal oxide film at the interface between the active layer and said insulating film containing silicon as a main component;
• and
• performing heat treatment under gaseous nitrogen atmosphere to thereby improve the film quality of said insulating film containing silicon as a main component inclusive of said thermal oxide film.

A method for fabricating a thin film transistor comprising:

• forming an insulating film on a surface of a substrate;
• forming at least a concave or a convex pattern intentionally on said insulating film;
• forming a semiconductor film in contact with an upper surface of said insulating film;
• forming a catalyst for promoting crystallization of said semiconductor film in contact with said semiconductor film;
• crystallizing said semiconductor film to form a plurality of columnar or needle-like crystals in parallel with said substrate therein;
• irradiating said semiconductor film with a laser light or an intense light having an energy equivalent to said laser light to aggregate said plurality of columnar or needle-like crystals so that at least a monodomain region is formed, said monodomain region being regarded as substantially a single crystal.

A method for fabricating a thin film transistor comprising:

• forming an insulating film on a surface of a substrate;
• forming at least a concave or a convex pattern intentionally on said insulating film;
• forming a semiconductor film in contact with an upper surface of said insulating film;
• forming a catalyst for promoting crystallization of said semiconductor film in contact with said semiconductor film;
• crystallizing said semiconductor film to form a plurality of columnar or needle-like crystals substantially in parallel with said substrate therein;
• irradiating said semiconductor film with a laser light or an intense light having an energy equivalent to a laser light to aggregate said plurality of columnar or needle-like crystals so that at least a monodomain region is formed, said monodomain region being substantially free of crystal grain boundaries.

A method of manufacturing a thin film transistor comprising:

• forming a silicon oxide film by sputtering on a surface of a substrate having an insulating surface;
• intentionally forming at least a concave or convex pattern by patterning said silicon oxide film into a predetermined shape;
• forming an amorphous silicon film by low pressure thermal CVD on said silicon oxide film;
• forming a metallic element which accelerates crystallization to said silicon oxide film and/or said amorphous silicon film;
• crystallizing said amorphous silicon film into a crystalline silicon film by heat treatment;
• and
• irradiating a laser light or an intense light having an energy equivalent to that of the laser light to said crystalline silicon film to thereby modify said crystalline silicon film into a monodomain region.

A method for fabricating a thin film transistor comprising:

• forming an insulating film on a surface of a substrate;
• forming at least a concave or a convex pattern intentionally on said insulating film;
• forming a semiconductor film in contact with an upper surface of said insulating film;
• forming a catalyst for promoting crystallization of said semiconductor film in contact with said semiconductor film;
• crystallizing said semiconductor film to form a plurality of columnar or needle-like crystals in parallel with said substrate therein;
• irradiating said semiconductor film with a laser light or an intense light having an energy equivalent thereto to aggregate said plurality of columnar or needle-like crystals so that at least a monodomain region is formed, said monodomain region being substantially a single crystal,
• wherein an active layer of said thin film transistor is formed by said monodomain region alone.

A method for fabricating a thin film transistor comprising:

• forming an insulating film on a surface of a substrate;
• forming at least a concave or a convex pattern intentionally on said insulating film;
• forming a semiconductor film in contact with an upper surface of said insulating film;
• forming a catalyst for promoting crystallization of said semiconductor film in contact with said semiconductor film;
• crystallizing said semiconductor film to form a plurality of columnar or needle-like crystals in parallel with said substrate therein;
• irradiating said semiconductor film with a laser light or an intense light having an energy equivalent to said laser light to aggregate said plurality of columnar or needle-like crystals so that at least a monodomain region is formed, said monodomain region being substantially free of crystal grain boundaries;
• and
• patterning said monodomain region to form an active layer on said thin film transistor,
• wherein said active layer of said thin film transistor includes no grain boundary.

A method of manufacturing a semiconductor device comprising:

• forming a silicon oxide film by sputtering on a surface of a substrate having an insulating surface;
• intentionally forming at least a concave or convex pattern by patterning said silicon oxide film into a predetermined shape;
• forming an amorphous silicon film by low pressure thermal CVD on said silicon oxide film;
• forming a metallic element which accelerates the crystallization to said amorphous silicon film;
• crystallizing the amorphous silicon film into a crystalline silicon film by heat treatment;
• and
• irradiating a laser light or an intense light having an energy equivalent to that of said laser light to said crystalline silicon film to thereby modify said crystalline silicon film into a monodomain region, wherein an active layer is formed by said monodomain alone.

A method of manufacturing a semiconductor device having an active layer made from a thin film semiconductor, said method comprising:

• forming a silicon oxide film by sputtering on the surface of a substrate having an insulating surface;
• intentionally forming at least a concave or convex pattern by patterning said silicon oxide film into a shape;
• forming an amorphous silicon film by low pressure thermal CVD on said silicon oxide film;
• forming a metallic element which accelerates crystallization to said amorphous silicon film;
• crystallizing said amorphous silicon film into a crystalline silicon film by heat treatment;
• irradiating a laser light or an intense light having an energy equivalent to that of said laser light to the crystalline silicon film, to thereby modify said crystalline silicon film into a monodomain region;
• forming an active layer by using said monodomain region alone;
• forming an insulating film covering said active layer and containing silicon as a main component by vapor phase method;
• performing heat treatment in an atmosphere containing a halogen element for gettering and removing metallic element which accelerates said crystallization of said active layer and, at the same time, forming a thermal oxide film at the interface between said active layer and said insulating film having silicon as a main component;
• and
• performing heat treatment under gaseous nitrogen atmosphere to thereby improve the film quality of said insulating film containing silicon as a main component including said thermal oxide film.

A method for fabricating a semiconductor device having an active layer made from a thin film semiconductor on an insulating film formed on the upper side of active circuits being integrated on a silicon substrate, said method comprising:

• forming at least a concave or a convex pattern intentionally on said insulating film;
• forming a semiconductor film in contact with an upper surface of said insulating film;
• forming a catalyst for promoting crystallization of said semiconductor film in contact with said semiconductor film;
• crystallizing said semiconductor film to form a plurality of columnar or needle-like crystals in parallel with said substrate therein;
• irradiating said semiconductor film with a laser light or an intense light having an energy equivalent to a laser light to aggregate said plurality of columnar or needle-like crystals so that at least a monodomain region is formed, said monodomain region being substantially free of crystal grain boundaries, and
• forming an active layer of said thin film transistor from only said monodomain region.