Patent attributes
A method for forming a thin-film transistor on an insulating substrate includes the steps of: forming a non-single-crystal semiconductor thin film on the insulating substrate; forming a gate insulating film on the non-single-crystal semiconductor thin film; forming a gate electrode including a lower gate electrode and an upper gate electrode on the gate insulating film, the lower gate electrode having a portion that is not covered by the upper gate electrode; forming a source-drain region and an LDD (lightly doped drain) region in the non-single-crystal thin film semiconductor film concurrently by introducing an impurity into the non-single-crystal semiconductor thin film through the gate electrode and the gate insulating film; and etching away an exposed portion of the lower gate electrode by using the upper gate electrode as a mask.
