Method of fabricating semiconductor devices by crystallizing amorphous silicon with nickel

A method of fabricating semiconductor devices, comprising the steps of:

• forming an amorphous silicon film on an insulating substrate;
• forming a first dielectric film on said amorphous silicon film to a thickness sufficient for said first dielectric film to act as an antireflective film for laser light having a given wavelength;
• forming holes in said dielectric film to selectively expose a surface of said amorphous silicon film;
• introducing a metal element into said amorphous silicon film from said exposed surface;
• crystallizing said amorphous silicon film by catalytic action of said metal element to form a crystalline silicon film;
• illuminating said crystalline silicon film with said laser light;
• etching said crystalline silicon film into an island while leaving said dielectric film on said crystalline silicon film to form an active layer;
• and
• forming a second dielectric film.

A method of fabricating semiconductor devices, comprising the steps of:

• forming a first dielectric film on an amorphous silicon film to a thickness sufficient for said first dielectric film to act as an antireflective film for laser light having a given wavelength, said first dielectric film forming a bottom layer of a gate-insulating film, said thickness of said first dielectric film being less than thickness of said gate-insulating film;
• forming holes in said dielectric film to selectively expose a surface of said amorphous silicon film;
• introducing a metal element into said amorphous silicon film from said exposed surface;
• crystallizing said amorphous silicon film to form a crystalline silicon film;
• illuminating said crystalline silicon film with said laser light;
• etching said crystalline silicon film into an island while leaving said dielectric film on said crystalline silicon film to form an active layer;
• and
• forming a second dielectric film which forms a top layer of said gate-insulating film,
• wherein said gate-insulating film comprises a laminate of said first dielectric film and said second dielectric film.

A method of fabricating semiconductor devices, comprising the steps of:

• forming an amorphous silicon film on an insulating substrate;
• forming a first dielectric film on said amorphous silicon film;
• forming holes in said dielectric film to selectively expose a surface of said amorphous silicon film;
• introducing a metal element into said amorphous silicon film from said exposed surface;
• crystallizing said amorphous silicon film by catalytic action of the metal element to form a crystalline silicon film;
• removing a surface portion of said first dielectric film heavily doped with said metal element;
• illuminating said crystalline silicon film with laser light;
• etching said crystalline silicon film into an island while leaving said dielectric film on said crystalline silicon film to form an active layer;
• and
• forming a second dielectric film.

A method of fabricating semiconductor devices, comprising the steps of:

• forming an amorphous silicon film on an insulating substrate;
• forming a first dielectric film on said amorphous silicon film;
• forming holes in said first dielectric film to selectively expose a surface of said amorphous silicon film;
• introducing a metal element into said amorphous silicon film from said exposed surface;
• crystallizing said amorphous silicon film by catalytic action of the metal element to form a crystalline silicon film;
• illuminating said crystalline silicon film with a laser light;
• removing a surface portion of said first dielectric film heavily doped with said metal element;
• etching said crystalline silicon film into an island while leaving said dielectric film on said crystalline silicon film to form an active layer;
• and
• forming a second dielectric film,
• wherein said first dielectric film is reduced to a thickness sufficient to act as an antireflective film for said laser light, by said removing step.