Thin-film transistor

Abstract

Abstract PURPOSE:To catch optical carriers in a region having the same conduction type as sections except a source and a drain of the thin-film FET, to decrease the carriers in an active region and to prevent the variation of the characteristics of the FET due to optical irradiation by forming the region having the same conduction type as the sections except the source and the drain to the sections except the source and the drain. CONSTITUTION:N Type poly Si 10 is formed onto a substrate 1 as an optical trap region, a P layer 2 is stacked, and the FET with the N<+> type source and drain 8, 9 is shaped according to a predetermined method. In the FET, N type carriers are caught by the N layer 10 and the optical carriers decrease, most of the carriers caught are surface-recombined with the adjacent substrate and extinguished, and the life of the carriers is shortened. Since an amorphous or low crystalline Si layer is used for the trap region 10, the life of the optical carriers is further shortened by bulk recombination, and the effect of the optical carriers in the active region is decreased remarkably. Accordingly, the variation of the characteristics of the FET is markedly slight even under optical irradiation.

Inventors

• 👤 Seigo Togashi

Bibliographic Details