Study of Two-Dimensional Electron Gases for GaN-Based Heterostructure

Two dimensional electron gas (2DEG) sheet carrier density is investigated for AlGaN/GaN, AlN/GaN and InGaN/GaN heterostructures using a self-consistent Schrödinger-Poisson equation simulator. The simulation also takes into account the underlying physics behind the characteristics of the 2DEG density nature. The dependence of 2DEG density on alloy composition, thickness of the channel layer and the change of gate voltage are investigated in the process. This simulation displays the comparison of 2DEG sheet carrier density among different heterostructures. The maximum 2DEG sheet carrier density obtained for AlGaN/GaN is 1.76×10¹³ cm^-2, for AlN/GaN is 2.16×10¹³ cm^-2 and for InGaN/GaN is 1.82×10¹³ cm^-2 without any bias voltage.