AlGaN/GaN异质结2DEG载流子输运

ELECTRON TRANSPORT IN 2DEG IN AlGaN/GaN HETEROSTRUCTURES

本文采用雷丁平衡方程理论，考虑杂质散射、声学波形变势散射、声学波压电散射、极化光学波散射等散射机制，计算了ＡｌＧａＮ／ＧａＮ 异质结二维电子气（２ＤＥＧ）在０３００Ｋ 温度范围内的低场迁移率以及电子漂移速度和电子温度随外加电场的变化关系，同时本文计算了有隔离层的调制掺杂异质结构（ＭＤＨ） 中低温下（Ｔ＝４Ｋ） 低场迁移率随隔离层厚度的变化关系。计算结果表明在低温下ＡｌＧａＮ／ＧａＮ异质结构的低场迁移率可高达３ ×１０６ｃｍ２／Ｖｓ； 对应ＧａＮ 材料中不同的杂质浓度，应采用不同的隔离层厚度以获得较大的迁移率。

Based on the Lei-Ting balance-equation approach we have theoretically studied electron transport characteristics of two-dimensional electron Gas (2DEG) in the modulation-doped AlGaN/GaN heterostructure,with an accurate treatment of the realistic scatterings by impurities, acoustic phonons, and polar-optic phonons.Ohmic mobility in the lattice-temperature range of 0-300 K and hot-electron transport property are calculated. It is shown that, for an optimized AlGaN/GaN heterostructure, its ohmic mobility can reach 4×10 6 cm 2 /Vs. In addition, the dependence of the ohmic mobility on the remote doping concentration and the spacer width is also discussed.