Patent ID: 8664652

Claim:
A semiconductor device comprising: an oxide semiconductor layer; a source electrode and a drain electrode electrically connected to the oxide semiconductor layer; a gate insulating layer covering the oxide semiconductor layer, the source electrode, and the drain electrode; and a gate electrode over the gate insulating layer, wherein a thickness of the oxide semiconductor layer is greater than or equal to 1 nm and less than or equal to 10 nm, wherein the gate insulating layer satisfies a relation where ∈ r /d is greater than or equal to 0.08 (nm −1 ) and less than or equal to 7.9 (nm −1 ) when a relative permittivity of a material used for the gate insulating layer is ∈ r and a thickness of the gate insulating layer is d, and wherein a distance between the source electrode and the drain electrode is greater than or equal to 10 nm and less than or equal to 1 μm.