Insulating film and method of producing semiconductor device

A semiconductor device comprising:

• a crystalline semiconductor island on an insulating surface;
• and
• an insulating film including silicon oxide to cover the crystalline semiconductor island,
• wherein the insulating film includes halogen at a concentration of 5×1020 cm−3 or less and carbon at a concentration of 5×1019 cm−3 or less.

A semiconductor device including at least a thin film transistor comprising:

• a crystalline semiconductor island on an insulating surface;
• a silicon oxide film over the crystalline semiconductor island;
• and
• a conductive film including at least one of aluminum, titanium, and titanium nitride, said conductive film being formed on the silicon oxide film,
• wherein the silicon oxide film includes halogen at a concentration of 5×1020 cm−3 or less and carbon at a concentration of 5×1019 cm−3 or less.

A semiconductor device including at least a thin film transistor comprising:

• a crystalline semiconductor island on an insulating surface;
• a gate insulating film including silicon oxide on the crystalline semiconductor island;
• and
• a gate electrode on the gate insulating film,
• wherein the gate insulating film includes halogen at a concentration of 5×1020 cm−3 or less and carbon at a concentration of 5×1019 cm−3 or less.