摘要
Ga_(2)O_(3)是一种新兴的宽带隙半导体,在电力和射频电子系统中具有潜在的应用前景。前期研究以β-Ga_(2)O_(3)为主,并且已经对β-(Al_(x)Ga_(1-x))_(2)O_(3)/Ga_(2)O_(3)异质结构中的二维电子气(2DEG)进行了理论计算,本文主要研究ε-(Al_(x)Ga_(1-x))_(2)O_(3)作为势垒层对ε-(Al_(x)Ga_(1-x))_(2)O_(3)/ε-Ga_(2)O_(3)异质结电子输运性质的影响,首先介绍了ε-(Al_(x)Ga_(1-x))_(2)O_(3)/ε-Ga_(2)O_(3)异质结的结构和性质,分析计算了由于ε-(Al_(x)Ga_(1-x))_(2)O_(3)/ε-Ga_(2)O_(3)异质结的自发极化和压电极化所产生的极化面电荷密度,以及极化对2DEG浓度产生的影响,接着分析了在不同Al摩尔组分下,ε-(Al_(x)Ga_(1-x))_(2)O_(3)势垒层厚度与合金无序散射、界面粗糙度散射和极性光学声子散射之间的关系。最后通过计算得出结论:界面粗糙度散射和极性光学声子散射对ε-(Al_(x)Ga_(1-x))_(2)O_(3)/ε-Ga_(2)O_(3)异质结的电子输运性质有重要影响,合金无序散射对异质结的输运性质影响较小;2DEG浓度、合金无序散射、界面粗糙度散射和极性光学声子散射的电子迁移率强弱由ε-(Al_(x)Ga_(1-x))_(2)O_(3)势垒层的厚度和Al摩尔组分共同决定。
Ga_(2)O_(3)is an emerging wide bandgap semiconductor with potential applications in power and RF electronic systems.Previous studies have focused onβ-Ga_(2)O_(3),and theoretical caculations have been made on the two-dimensional electronic gas(2DEG)inβ-(Al_(x)Ga_(1-x))_(2)O_(3)/Ga_(2)O_(3) heterojunction.In this paper,the effect ofε-(Al_(x)Ga_(1-x))_(2)O_(3) as a potential barrier on the electron transport properties ofε-(Al_(x)Ga_(1-x))_(2)O_(3)/ε-Ga_(2)O_(3) heterojunction was studied.Firstly,the structure and properties ofε-(Al_(x)Ga_(1-x))_(2)O_(3)/ε-Ga_(2)O_(3) heterojunction are introduced.The charge density on the polarization surface caused by spontaneous polarization and piezoelectric polarization ofε-(Al_(x)Ga_(1-x))_(2)O_(3)/ε-Ga_(2)O_(3) heterojunction and the effect of polarization on the concentration of 2DEG were analyzed and calculated.Then,the relationship betweenε-(Al_(x)Ga_(1-x))_(2)O_(3) barrier thickness and alloy disorder scattering,interface roughness scattering and polar optical phonon scattering were analyzed under different Al mole composition.Finally,it is concluded that the interface roughness scattering and polar optical phonon scattering have important effects on the electron transport properties ofε-(Al_(x)Ga_(1-x))_(2)O_(3)/ε-Ga_(2)O_(3) heterojunction,and the alloy disorder scattering has little effect on the electron transport properties ofε-(Al_(x)Ga_(1-x))_(2)O_(3)/ε-Ga_(2)O_(3) heterojunction.The electron mobility of 2DEG concentration,alloy disorder scattering,interface roughness scattering and polar optical phonon scattering are determined by the thickness ofε-(Al_(x)Ga_(1-x))_(2)O_(3) barrier layer and the Al mole composition.
作者
白雅楠
吕燕伍
BAI Yanan;LYU Yanwu(School of Science, Beijing Jiaotong University, Beijing 100044, China)
出处
《人工晶体学报》
CAS
北大核心
2022年第3期441-449,共9页
Journal of Synthetic Crystals
基金
国家自然科学基金(60976070)。
