Xu Peiqiang, Jiang Yang, Chen Yao, Ma Ziguang, Wang Xiaoli, Deng Zhen, Li Yan, Jia Haiqiang, Wang Wenxin, Chen Hong
Beijing National Laboratory of Condensed Matter Physics, Institute of Physics, Chinese Academy of Sciences, No, 8, 3rd South Street, Zhongguancun, Haidian District, Beijing, 100190, People's Republic of China.
Nanoscale Res Lett. 2012 Feb 20;7(1):141. doi: 10.1186/1556-276X-7-141.
GaN-based high-electron mobility transistors (HEMTs) with AlN/GaN super-lattices (SLs) (4 to 10 periods) as barriers were prepared on (0001) sapphire substrates. An innovative method of calculating the concentration of two-dimensional electron gas (2-DEG) was brought up when AlN/GaN SLs were used as barriers. With this method, the energy band structure of AlN/GaN SLs was analyzed, and it was found that the concentration of 2-DEG is related to the thickness of AlN barrier and the thickness of the period; however, it is independent of the total thickness of the AlN/GaN SLs. In addition, we consider that the sheet carrier concentration in every SL period is equivalent and the 2-DEG concentration measured by Hall effect is the average value in one SL period. The calculation result fitted well with the experimental data. So, we proposed that our method can be conveniently applied to calculate the 2-DEG concentration of HEMT with the AlN/GaN SL barrier.
在（0001）蓝宝石衬底上制备了以AlN/GaN超晶格（SLs）（4至10个周期）为势垒的氮化镓基高电子迁移率晶体管（HEMTs）。当使用AlN/GaN SLs作为势垒时，提出了一种计算二维电子气（2-DEG）浓度的创新方法。通过该方法，分析了AlN/GaN SLs的能带结构，发现2-DEG的浓度与AlN势垒的厚度和周期厚度有关；然而，它与AlN/GaN SLs的总厚度无关。此外，我们认为每个SL周期中的面载流子浓度是等效的，并且通过霍尔效应测量的2-DEG浓度是一个SL周期中的平均值。计算结果与实验数据吻合良好。因此，我们提出我们的方法可以方便地应用于计算具有AlN/GaN SL势垒的HEMT的2-DEG浓度。
