表面态对AlGaN／GaN异质结构2DEG影响的模拟分析

Influence of surface state on 2DEG formation at AlGaN/GaN heterostructure

利用模拟软件研究施主表面态特性与AlGaN/GaN异质结构中二维电子气(2dimensional electron gas,2DEG)形成之间的关系,分析施主表面态电离过程以及表面态能级位置、表面态密度的影响。结果表明:施主表面态为2DEG的电子来源;AlGaN能带分布及2DEG密度随AlGaN厚度、施主表面态能级位置、施主表面态密度的改变而改变。

The influence of surface state on two-dimensional electronic gas （2DEG）formation at AlGaN/GaN heterostructure is simulated.Specifically,the effects of AlGaN thickness,surface state energy level and surface state density changing are ana-lyzed.It is demonstrated that the electrons of 2DEG are primarily originated from surface state ionization.Simultaneously,Al-GaN thickness,surface state energy level and surface state density would be changed with the changes of AlGaN band structure and 2DEG density.