A Schottky diode and method of fabricating the Schottky diode using gallium nitride (GaN) materials is disclosed. The method includes providing an n-type GaN substrate having first and second opposing surfaces. The method also includes forming an ohmic metal contact electrically coupled to the first surface, forming an n-type GaN epitaxial layer coupled to the second surface, and forming an n-type aluminum gallium nitride (AlGaN) surface layer coupled to the n-type GaN epitaxial layer. The AlGaN surface layer has a thickness which is less than a critical thickness, and the critical thickness is determined based on an aluminum mole fraction of the AlGaN surface layer. The method also includes forming a Schottky contact electrically coupled to the n-type AlGaN surface layer, where, during operation, an interface between the n-type GaN epitaxial layer and the n-type AlGaN surface layer is substantially free from a two-dimensional electron gas.