| abstract |
A control and channel resistance reducing A gate electrode of the threshold voltage of the field effect transistor, an undoped In 0.2 Ga 0.8 N / undoped Al 0.2 Ga 0.8 N / undoped GaN This is a field effect transistor comprising a heterojunction. Since In 0.2 Ga 0.8 N has a large piezo electric field effect, a large piezo electric field is generated by applying a large stress strain to this hetero-grown layer. Thereby, the conduction band of Al 0.2 Ga 0.8 N and GaN can be raised, and the channel level can be raised. Thereby, it can be a normally-off type, and the channel resistance can be greatly reduced by forming the electric field generating layer only under the gate electrode. [Selection] Figure 1 |