The impact of atomic layer bombardment (ALB) on the aluminum nitride (AlN) passivation layer between the HfO₂ gate dielectric and the n-type epitaxial germanium (Ge) was investigated. The ALB technique was performed with the layer-by-layer, in situ helium/argon plasma bombardment in each cycle of atomic layer deposition (ALD) of AlN. An increase in the film density and a decrease in nitrogen vacancies, as manifested by the X-ray reflection and X-ray spectroscopy, were observed in the AlN layer treated by the ALB process. The improvements in the AlN quality contribute to a reduction of the equivalent oxide thickness from 1.36 to 1.19 nm of the AlN/HfO₂ gate stack, together with the suppression of the gate leakage current, the interfacial state density, and the slow trap density. The reliability tests reveal promising reliability of the AlN/HfO₂ gate stack with a small flat-band voltage shift under the constant voltage stress and a high operation voltage of ∼2.4 V projected for a 10 years time-dependent-dielectric-breakdown lifetime. All of the results point that the ALB technique can effectively enhance the material/interface properties, electrical characteristics, and reliability of nanoscale devices, which is critical and beneficial to the next-generation high-speed and low-power nanoelectronics.

中文翻译：

---

外延Ge上AlN钝化层的原子层致密化，以增强高K栅堆叠的可靠性和电性能

研究了原子层轰击（ALB）对HfO ₂栅极电介质和n型外延锗（Ge）之间的氮化铝（AlN）钝化层的影响。ALB技术是在AlN原子层沉积（ALD）的每个循环中，逐层进行原位氦/氩等离子体轰击。在通过ALB工艺处理的AlN层中，观察到膜密度的增加和氮空位的减少，如通过X射线反射和X射线光谱学所证明的。AlN质量的提高有助于将AlN / HfO ₂的等效氧化物厚度从1.36 nm降低到1.19 nm栅堆叠，以及对栅漏电流，界面态密度和慢陷阱能级的抑制。可靠性测试表明，AlN / HfO ₂栅堆叠具有可观的可靠性，在恒定电压应力下具有较小的平带电压偏移，并且预计在10年内具有与时间相关的介电击穿寿命，其工作电压约为2.4V。所有结果都表明，ALB技术可以有效地增强纳米级器件的材料/界面特性，电学特性和可靠性，这对于下一代高速和低功率纳米电子学来说至关重要。