A semiconductor apparatus includes, a first silicon layer of a first conductivity type; a second silicon layer provided on the first silicon layer and having a higher resistance than the first silicon layer, a third silicon layer of a second conductivity type provided on the second silicon layer, a first nitride semiconductor layer provided on the third silicon layer, a second nitride semiconductor layer provided on the first nitride semiconductor layer and having a larger bandgap than the first nitride semiconductor layer, a first main electrode being in contact with a surface of the second nitride semiconductor layer and connected to the third silicon layer, a second main electrode being in contact with the surface of the second nitride semiconductor layer and connected to the first silicon layer, and a control electrode provided between the first main electrode and the second main electrode on the second nitride semiconductor layer.