Thin film transistor and manufacturing method thereof

摘要

The present invention provides a thin film transistor in which a substantial length of a channel is shortened to miniaturize a semiconductor device and a manufacturing method thereof. In addition, the present invention provides a semiconductor device which realizes high-speed operation and high-performance of the semiconductor device and a manufacturing method thereof. Further in addition, it is an object of the present invention to provide a manufacturing method in which a manufacturing process is simplified. The semiconductor device of the present invention has an island-shaped semiconductor film formed over a substrate having an insulating surface and a gate electrode formed over the island-shaped semiconductor film, in which the gate electrode is oxidized its surface by high-density plasma to be slimmed and the substantial length of a channel is shortened.