The invention provides a layer structure for an n type or p type channel transistor and a plane reverse circuit. In one embodiment, the layer structure can be used for producing the n type channel transistor. The layer structure includes a first semiconductor layer having a conduction band minimum EC1; a second semiconductor layer having a discrete hole level H0; a wide bandgap semiconductor barrier layer disposed between the first and the second semiconductor layers; a gate dielectric layer disposed above the first semiconductor layer; and a gate metal layer disposed above the gate dielectric layer; wherein the discrete hole level H0 is positioned below the conduction band minimum Ec1 for zero bias applied to the gate metal layer. Using the transistor of the layer structure, the average effective quality is increased and the channel carrier density and the drain current can be changed with a rush.