摘要 |
Provided is a semiconductor device capable of suppressing an occurrence of a punch-through phenomenon. A semiconductor device includes a substrate 1, a first n-type semiconductor layer 2, a p-type semiconductor layer 3, a second n-type semiconductor layer 4, a drain electrode 13, a source electrode 11, a gate electrode 12, and a gate insulation film 21, wherein the first n-type semiconductor layer 2, the p-type semiconductor layer 3, and the second n-type semiconductor layer 4 are laminated on the substrate 1 in this order. The drain electrode 13 is in ohmic-contact with the first n-type semiconductor layer 2. The source electrode 11 is in ohmic-contact with the second n-type semiconductor layer 4. An opening portion to be filled or a notched portion that extends from an upper surface of the second n-type semiconductor layer 4 to an upper part of the first n-type semiconductor layer 2 is formed at a part of the p-type semiconductor layer 3 and a part of the second n-type semiconductor layer 4. The gate electrode 12 is in contact with an upper surface of the first n-type semiconductor layer 2, side surfaces of the p-type semiconductor layer 3, and side surfaces of the second n-type semiconductor layer 4 at inner surfaces of the opening portion to be filled or a surface of the notched portion via the gate insulation film 21. The p-type semiconductor layer 3 has a positive polarization charge at a first n-type semiconductor layer 2 side in a state where a voltage is applied to none of the electrodes. |