Patent ID: 8389417

Claim:
A semiconductor device comprising: a first transistor including: impurity regions provided in a substrate including a semiconductor material; a channel formation region between the impurity regions; a first gate insulating layer over the channel formation region; a first gate electrode over the first gate insulating layer; and a first source electrode and a first drain electrode electrically connected to the impurity regions; and a second transistor including: an oxide semiconductor layer over the substrate including the semiconductor material; a second source electrode and a second drain electrode electrically connected to the oxide semiconductor layer; a second gate insulating layer covering the oxide semiconductor layer, the second source electrode, and the second drain electrode; and a second gate electrode over the second gate insulating layer, wherein the second source electrode and the second drain electrode include an oxide region at a side surface of the second source electrode and the second drain electrode, and wherein at least one of the first gate electrode, the first source electrode, and the first drain electrode is electrically connected to at least one of the second gate electrode, the second source electrode, and the second drain electrode.