SEMICONDUCTOR DEVICE

摘要

A semiconductor device in which variation in electrical characteristics between transistors is reduced is provided. A transistor where a channel is formed in an oxide semiconductor layer is included, and a concentration of carriers contained in a region where the channel is formed in the oxide semiconductor layer is lower than or equal to 1×1015/cm3, preferably lower than or equal to 1×1013/cm3, more preferably lower than or equal to 1×1011/cm3, whereby an energy barrier height which electrons flowing between a source and a drain should go over converges at a constant value. In this manner, a semiconductor device in which variation in the electrical characteristics between the transistors is inhibited is provided.

主权项

1. A semiconductor device comprising:
a gate electrode layer; an oxide semiconductor layer overlapping with the gate electrode layer; a gate insulating layer between the gate electrode layer and the oxide semiconductor layer; and a source electrode layer and a drain electrode layer overlapping with part of the oxide semiconductor layer, wherein a donor concentration of a channel formation region in the oxide semiconductor layer is lower than or equal to 1×1015/cm3, and wherein the following Formula (1) is satisfied.
(Ec1−Ef1)