Ge has been an alternative channel material for the performance enhancement of complementary metal–oxide–semiconductor (CMOS) technology applications because of its high carrier mobility and superior compatibility with Si CMOS technology. The gate structure plays a key role on the electrical property. In this paper, the property of Ge MOSFET with Al₂O₃/GeO _x /Ge stack by ozone oxidation is reviewed. The GeO _x passivation mechanism by ozone oxidation and band alignment of Al₂O₃/GeO _x /Ge stack is described. In addition, the charge distribution in the gate stack and remote Coulomb scattering on carrier mobility is also presented. The surface passivation is mainly attributed to the high oxidation state of Ge. The energy band alignment is well explained by the gap state theory. The charge distribution is quantitatively characterized and it is found that the gate charges make a great degradation on carrier mobility. These investigations help to provide an impressive understanding and a possible instructive method to improve the performance of Ge devices.

中文翻译：

---

臭氧氧化对具有 GeO x /Al2O3 栅极叠层的 Ge MOSFET 的钝化、能带对齐、栅极电荷和迁移率退化的研究

Ge 因其高载流子迁移率和与 Si CMOS 技术的卓越兼容性而成为互补金属氧化物半导体 (CMOS) 技术应用性能增强的替代通道材料。栅极结构对电性能起着关键作用。本文研究了具有 Al ₂ O ₃ /GeO的 Ge MOSFET 的特性 _X /审查了臭氧氧化的锗堆。GeO _X 臭氧氧化钝化机制和 Al ₂ O ₃ /GeO的带排列 _X /ge 堆栈描述。此外，还介绍了栅极堆叠中的电荷分布和远程库仑散射对载流子迁移率的影响。表面钝化主要归因于Ge的高氧化态。带隙状态理论很好地解释了能带排列。对电荷分布进行了定量表征，发现栅极电荷对载流子迁移率有很大影响。这些研究有助于提供令人印象深刻的理解和可能的指导方法，以提高 Ge 器件的性能。