The two dimensional eelectron gas in BST/Al0.3Ga0.7N/GaN double heterostructure

摘要

In this paper, we take account of spontaneous and piezoelectric polarization effect of BST and AlGaN. At the hetero-interface in BST/ Al0.3Ga0.7N /GaN double heterostructure, one-dimensional Poisson-Schrodinger equation using nonuniform mesh are solved self-consistently in dependence of the polarization and thickness of BST and the thickness of AlGaN barrier layer. BST/Al0.3Ga0.7N/GaN double heterostructure conduction band and the two-dimensional electron gas(2DEG) density are investigated. The results indicate that the 2DEG density of BST/Al0.3Ga0.7N/GaN is larger than that of Al0.3Ga0.7N/GaN, for a 8nm BST on AlGaN/GaN structure, the 2DEG density reached 1.85×10¹³ cm⁻², which is 23% higher than that of AlGaN/GaN structure.