Method for forming a semiconductor device

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

• forming a semiconductor film on an insulting surface by a CVD using a silane which is not diluted with hydrogen, as a reactive gas;
• crystallizing said semiconductor film by irradiating a laser light thereto;
• preparing an atmosphere comprising a dopant gas diluted with hydrogen wherein said dopant gas comprises a compound of a dopant impurity;
• converting said atmosphere to plasma by applying an electrical energy thereto;
• and
• introducing said dopant impurity into the crystalline semiconductor film by using said plasma.

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

• forming a semiconductor film on an insulating surface by a CVD using a silane which is not diluted with hydrogen, as a reactive gas;
• crystallizing said semiconductor film;
• preparing an atmosphere comprising a dopant gas diluted with hydrogen gas wherein said dopant gas comprises a compound of a dopant impurity;
• converting said atmosphere to a plasma by applying an electrical energy thereto and
• introducing said dopant impurity into the crystalline semiconductor film by using said plasma.

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

• forming a semiconductor film comprising amorphous silicon and hydrogen on an insulting surface;
• drawing hydrogen out of said semiconductor film;
• crystallizing said semiconductor film;
• preparing an atmosphere comprising a dopant gas diluted with hydrogen wherein said dopant gas comprises a compound of a dopant impurity including a trivalent or a pentavalent atom;
• converting said atmosphere to a plasma by applying an electrical energy thereto;
• and
• introducing said dopant impurity into the crystalline semiconductor film by using said plasma.

A method for forming a semiconductor device having a semiconductor island including at least source and drain regions, a channel region therebetween, and a gate electrode adjacent to said semiconductor island, said method comprising the steps of:

• forming a semiconductor film on an insulating surface;
• crystallizing said semiconductor film;
• patterning the crastalline semiconductor film into said semiconductor island;
• preparing an atmosphere comprising a dopant gas diluted with hydrogen wherein said dopant gas comprises a compound of a dopant impurity;
• converting said atmosphere to a plasma by applying an electrical energy thereto;
• and
• introducing said dopant impurity into selected portions of the semiconductor island to form said source and drain regions by using said plasma.

The method for forming a semiconductor device having a semiconductor island including at least source and drain regions, a channel region therebetween, and a gate electrode adjacent to said semiconductor island, said method comprising the steps of:

• forming a semiconductor film on an insulting surface;
• crystallizing said semiconductor film by irradiating a laser light thereto;
• patterning the crystalline semiconductor film into said semiconductor island;
• preparing an atmosphere comprising a dopant gas wherein said dopant gas comprises a compound of a dopant impurity;
• converting said atmosphere to a plasma by applying an electrical energy thereto;
• and
• introducing said dopant impurity into selected portions of the semiconductor island to form said source and drain regions by using said plasma.

A method for forming a semiconductor device having a semiconductor island including at least source and drain regions, a channel region therebetween and a gate electrode adjacent to said semiconductor island, said method comprising the steps of:

• forming a semiconductor film on an insulating surface by a CVD using a silane which is not diluted with hydrogen, as a reactive gas;
• crystallizing said semiconductor film;
• patterning the crystalline semiconductor film into said semiconductor island;
• preparing an atmosphere comprising a dopant gas diluted with the hydrogen gas wherein said dopant gas comprises a compound of a dopant impurity;
• converting said atmosphere to a plasma by applying an electrical energy thereto;
• and
• introducing said dopant impurity into selected portions of the semiconductor island to form said source and drain regions by using said plasma.

A method for forming a semiconductor device having a semiconductor island including at least source and drain regions, a channel region therebetween and a gate electrode adjacent to said semiconductor island, said method comprising the steps of:

• forming a semiconductor film comprising amorphous silicon and hydrogen on an insulating surface;
• drawing hydrogen out of said semiconductor film;
• crystallizing said semiconductor film;
• patterning the crystalline semiconductor film into said semiconductor island;
• preparing an atmosphere comprising a dopant gas diluted with hydrogen wherein said dopant gas comprises a compound of dopant impurity including a trivalent or a pentavalent atom;
• converting said atmosphere to a plasma by applying an electrical energy thereto;
• and
• introducing said dopant impurity into selected portion of the semiconductor island to form said source and drain regions by using said plasma.