Patent ID: 9553152
Date: 2017-01-24
CPC Classifications: H01L

Claim:
1. A semiconductor device comprising: a first semiconductor layer which is formed over a substrate and is formed from a nitride semiconductor; a second semiconductor layer which is formed over the first semiconductor layer and is formed from a nitride semiconductor; a third semiconductor layer which is formed over the second semiconductor layer and is formed from a nitride semiconductor; a source electrode and a drain electrode which are formed over the third semiconductor layer; a recess formed in the first semiconductor layer between the source electrode and the drain electrode; a trench penetrates the second semiconductor layer and the third semiconductor layer between the source electrode and the drain electrode, and reaches the recess; an insulating layer which is formed on a side surface and a bottom surface of the trench; and a gate electrode which is formed in the opening through the insulating layer, wherein the gate electrode includes a first gate electrode portion which is formed to come into contact with the insulating layer on a source electrode side, and a second gate electrode portion which is formed to come into contact with the insulating layer on a drain electrode side, the first gate electrode portion and the second gate electrode portion being formed in the trench, and the first gate electrode portion and the second gate electrode portion are formed from materials different from each other.