Zhao Lu, Liu Hongxia, Wang Xing, Wang Yongte, Wang Shulong
Key Laboratory for Wide Band Gap Semiconductor Materials and Devices of Education, School of Microelectronics, Xidian University, Xi'an 710071, China.
Materials (Basel). 2018 Nov 20;11(11):2333. doi: 10.3390/ma11112333.
In this paper, the impact of La₂O₃ passivation layers on the interfacial properties of Ge-based metal-insulator-semiconductor (MIS) structures was investigated. It was proven that the formation of a thermodynamically stable LaGeO component by incorporating a La₂O₃ interlayer could effectively suppress desorption of the interfacial layer from GeO₂ to volatile GeO. The suppression of GeO desorption contributed to the decrease in oxide trapped charges and interfacial traps in the bulk of the gate insulator, or the nearby interfacial regions in the Al₂O₃/La₂O₃/Ge structure. Consequently, the hysteretic behavior of the dual-swept capacitance-voltage (-) curves and the frequency dispersion of multi-frequency - curves were remarkably weakened. Besides, more than one order of magnitude decrease in the gate leakage current density, and higher insulator breakdown electric field were obtained after inserting a La₂O₃ passivation layer.
本文研究了La₂O₃钝化层对锗基金属-绝缘体-半导体（MIS）结构界面特性的影响。结果表明，通过引入La₂O₃中间层形成热力学稳定的LaGeO组分，可以有效抑制界面层从GeO₂解吸为挥发性的GeO。GeO解吸的抑制有助于减少栅极绝缘体主体或Al₂O₃/La₂O₃/Ge结构中附近界面区域的氧化物陷阱电荷和界面陷阱。因此，双扫描电容-电压（-）曲线的滞后行为和多频-曲线的频率色散显著减弱。此外，插入La₂O₃钝化层后，栅极漏电流密度降低了一个多数量级以上，并且绝缘体击穿电场更高。
