Abstract :
Based on the elastic continuum model and Fermi golden rule, the ternary mixed crystal effect and size effect on the mobility of two-dimensional electron gas influenced by the scattering from acoustic phonons via deformation potential in a wurtzite AlxGa1−xN/GaN/AlyGa1−yN double heterostructure at 77 K are discussed theoretically. The results show that the increase of the Al component in AlxGa1−xN barrier changes the symmetry and vibration modes of acoustic phonons, leading an abrupt increase of the total mobility in a certain Al component region for an asymmetrical heterostructure. Besides, the total mobility reaches a maximum around a certain thickness of channel layer GaN. These effects give a guidance to improve the properties of high electron mobility transistors.
