Semiconductor device

1. A semiconductor device, comprising:

a substrate; a carrier transit layer disposed above the substrate;

a compound semiconductor layer disposed on the carrier transit layer;

a source electrode disposed on the compound semiconductor layer;

a first groove disposed from a back of the substrate up to an inside of the carrier transit layer while penetrating the substrate;

a drain electrode disposed in the inside of the first groove;

a gate electrode located between the source electrode and the first groove and disposed on the compound semiconductor layer; and

a second groove located diagonally under the source electrode and between the source electrode and the first groove and disposed from the back of the substrate up to another inside of the carrier transit layer while penetrating the substrate.

2. The semiconductor device according to claim 1 ,

wherein the drain electrode is disposed at an interface or in the vicinity of an interface between the compound semiconductor layer and the carrier transit layer.

3. The semiconductor device according to claim 1 , further comprising an insulating film disposed on a side surface of the drain electrode.

4. The semiconductor device according to claim 1 , further comprising a stopper layer disposed between the substrate and the carrier transit layer,

wherein the first groove and the second groove penetrate the stopper layer.