A novel InxGa1−xN/InN heterostructure field-effect transistor with extremely high two-dimensional electron-gas sheet density

By self-consistently solving Schrödinger and Poisson equations, an extremely high two-dimensional electron-gas (2DEG) sheet density of 1.01 × 1014 cm−2 is calculated in a novel InN-based InxGa1−xN/InN heterostructure field-effect transistor with an In content of x = 0.1 and a doping level of Nd = 1 × 1019 cm−3 in the InxGa1−xN barrier layer. It is increased by almost one order of magnitude as compared to ∼1 × 1013 cm−2 obtained in a conventional GaN-based Al0.2Ga0.8N/GaN heterostructure. With increasing In content of the InxGa1−xN barrier from x = 0.05 to 0.15, the 2DEG sheet density decreases from 1.14 × 1014 cm−2 to 0.91 × 1014 cm−2 due to the decreased of polarization charges and the reduced conduction band offset. And the 2DEG density increases slightly with increasing doping level of the InxGa1−xN barrier.