A novel In xGa 1− xN/InN heterostructure field-effect transistor with extremely high two-dimensional electron-gas sheet density

Abstract

By self-consistently solving Schrödinger and Poisson equations, an extremely high two-dimensional electron-gas (2DEG) sheet density of 1.01 × 10 14 cm −2 is calculated in a novel InN-based In x Ga 1− x N/InN heterostructure field-effect transistor with an In content of x = 0.1 and a doping level of N d = 1 × 10 19 cm −3 in the In x Ga 1− x N barrier layer. It is increased by almost one order of magnitude as compared to ∼1 × 10 13 cm −2 obtained in a conventional GaN-based Al 0.2Ga 0.8N/GaN heterostructure. With increasing In content of the In x Ga 1− x N barrier from x = 0.05 to 0.15, the 2DEG sheet density decreases from 1.14 × 10 14 cm −2 to 0.91 × 10 14 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 In x Ga 1− x N barrier.