| abstract |
A semiconductor device comprising: a gate electrode on a substrate, a gate insulating layer on the gate electrode, an oxide semiconductor layer on the gate insulating layer, and a source electrode and a germanium on the oxide semiconductor layer Polar electrode. The length of the portion of the outer edge of the oxide semiconductor layer from the outer edge of the source electrode to the outer edge of the drain electrode is more than three times, more preferably five times or more, the length of the channel of the semiconductor device. Further, oxygen is supplied from the gate insulating layer to the oxide semiconductor layer by heat treatment. Further, an insulating layer is formed after selectively etching the oxide semiconductor layer. |