Patent ID: 7626205
Filing Date: 2009-12-01
Classification: C09K,H01L

Abstract:
1. A semiconductor device comprising: a substrate; and a thin film transistor that uses a polycrystalline silicon film disposed over the substrate as an active layer thereof, wherein the polycrystalline silicon film is sandwiched between a first gate insulation layer and a second gate insulation layer, the thin film transistor has a first thin film transistor portion and a second thin film transistor portion, the first thin film transistor portion has the same conductivity type as that of the second thin film transistor portion, the first thin film transistor portion and the second thin film transistor portion being connected in series, the first front gate electrode and the second front gate electrode are electrically connected to each other, and a source-side back gate electrode is formed at a region that is opposed to the second channel region with the second gate insulation layer being sandwiched therebetween, a source potential being applied to the source-side back gate electrode.