THIN-FILM TRANSISTOR CIRCUIT AND IMAGE DISPLAY DEVICE

摘要

PROBLEM TO BE SOLVED: To greatly improve the characteristics of a thin-film transistor circuit in terms of operation speed, holding characteristics, etc. SOLUTION: The thin-film transistor(TFT) circuit is constituted by forming plural TFTs on an insulating substrate 11. Conductive electrodes 14 are so arranged as to face gate electrodes 16 across the channel regions 12a of polycrystalline silicon thin films 12 constituting active layers of these TFTs. The same specified voltage is impressed on the conductive electrodes 14. The absolute value of the threshold voltage of n channel type transistors(TRs) and the absolute value of the threshold voltage of p channel type TRs are nearly equaled to each other if the threshold voltage is shifted by impressing the voltage on the conductive electrodes 14. The adequate setting of the threshold voltage according to the channel lengths of the TFTs, the kinds of the circuits constituted by the TFTs, the voltage impressed on the TFTs, etc., is made possible as well.