METHOD FOR MANUFACTURING THIN FILM TRANSISTOR

摘要

PURPOSE: A method for manufacturing a thin film transistor is provided to improve the property of the thin film transistor by completely solidifying an active layer without an LDD(Lightly Doped Drain) process. CONSTITUTION: A buffer film(203) and an amorphous silicon film are deposited on a glass substrate(201). The amorphous silicon film is solidified to form a polysilicon layer. The polysilicon layer is etched by laser beam to form an active layer(205A). A first gate insulating film(207), a gate film, and a gate auxiliary film(211) are deposited on the active layer. The gate film is isotropically etched to narrow the width of the gate film rather than the width of the gate auxiliary film. Source, drain, and channel areas are formed by injecting an N type impurity ion. The gate auxiliary film is removed by etching and the amorphous parts of the source and drain electrodes are thermally annealed to be solidified.