Field effect type thin film transistor

Abstract

Abstract PURPOSE:To increase the operating speed of the titled transistor by a method wherein a semiconductor layer is formed by the lamination of two layers of the first semiconductor film of 150Angstrom or less in thickness and the second semiconductor film of 1,000Angstrom or more in thickness having a larger band gap than the first film. CONSTITUTION:The gate electrode 6, gate insulation film 7, first semiconductor film 8 of 150Angstrom or less thickness made of microcrystallized Si or the like, source and drain 11 and 12, an amorphous Si film 13 the second semiconductor film of 1,000Angstrom thickness having a larger band gap than the film 8, and a protecting insulation film 14 are provided. When the thin film transistor of such a construction is turned on by impressing a positive voltage on its gate electrode, the electrons in the thickness direction of the layer 3 are quantized, and the electrons on the conduction band of this layer behave as the two dimensional electron gas; accordingly, a large density of free electrons can be obtained. Besides, the electrons flowing through the conduction band in an amorphous substance have a large mobility.

Inventors

• 👤 Tsuneo Yamazaki
• 👤 山崎　恒夫

Bibliographic Details