POLYSILICON THIN FILM SEMICONDUCTOR AND MANUFACTURING METHOD THEREFOR

摘要

PROBLEM TO BE SOLVED: To improve the fluctuation of display pictures due to the dispersion of the characteristic of driving TIFT by controlling the threshold voltage of a thin film transistor in a low temperature process in a picture display device. SOLUTION: In the manufacture of a thin film semiconductor device where a thin film transistor is integrated, a film which is close to an I (intrinsic) layer where impurity is not mixed in a thin film (sheet resistor is not less than 1.0×10<9> ohm/sq.) is used. For crystallizing an active layer, the threshold voltage of the thin film transistor can be adjusted by suppressing impurity contamination to under 1×10<17> /cm<3> .