| 摘要 |
PROBLEM TO BE SOLVED: To solve the problem that, when negative constant charge is introduced to a channel region of a nitride semiconductor, a threshold voltage increases such that normally-off can be implemented, but ON resistance may increase.SOLUTION: A channel region 12a opposite to a gate electrode 2 via a gate insulator 4 has a structure where a negative constant charge introduction region 14 and a non-introduction region 15 alternately appear when observed in a direction ((y) direction) where the gate electrode 2 extends. When a voltage is not applied to the gate electrode 2, a depletion layer extends in the (y) direction from the negative constant charge introduction region 14, and the non-introduction region 15 is depleted. When a voltage is applied to the gate electrode 2, the depletion layer is shrunk and channel resistance is reduced. A gate voltage for shrinking the depletion layer rises, thereby implementing normally-off. An electron moves in the non-introduction region 15 with high mobility, such that ON resistance is low. |
