arXivDaily arXiv每日学术速递 周一至周五更新
arXiv周末暂无论文更新,休息一下吧,周末愉快~~
arXiv 2102.03642cond-mat.mtrl-sci
收藏

无氧化剂等离子体辅助原子层沉积法在GaN上制备单层氧化铝

Aluminum Oxide at the Monolayer Limit via Oxidant-free Plasma-Assisted Atomic Layer Deposition on GaN

Alex Henning, Johannes D. Bartl, Andreas Zeidler, Simon Qian, Oliver Bienek, Chang-Ming Jiang, Claudia Paulus, Bernhard Rieger, Martin Stutzmann, Ian D. Sharp

摘要:

原子层沉积(ALD)是半导体器件制造中的重要工具,其允许外延和保形膜的生长以精确地形成异质结构并调节界面性质。ALD过程中化学反应的自限性提供了对层厚度的极好控制。然而,与理想化的生长模型相反,通过ALD产生连续单层在实验上是具有挑战性的,因为表面不均匀性和前体空间相互作用导致膜成核期间的岛状生长。因此,通过ALD产生无针孔单层的能力将为控制半导体器件中的界面电荷和质量传输以及定制表面化学提供新的机会。在这里,我们报告的c-平面氮化镓(GAN)与最终薄(~3微米)的氧化铝(AlOx)单层,这是通过使用三甲基铝沉积和氢等离子体暴露的组合的GAN表面氧化物的部分转化为AlOx实现的完全封装。单层AlOx的引入显著地改变了表面的物理和化学性质,降低了功函数并向GAN表面引入了新的化学反应性。这种可调的界面化学突出的改性表面与膦酸在标准条件下的反应性,这导致在自组装单分子膜的密度接近理论极限。更广泛地说,所提出的单层AlOx沉积方案可以扩展到其他基于III-V族和III-V族的半导体,与光电子学、化学传感和(光)电催化的应用具有显著的相关性。

英文摘要:

Atomic layer deposition (ALD) is an essential tool in semiconductor device fabrication that allows the growth of ultrathin and conformal films to precisely form heterostructures and tune interface properties. The self-limiting nature of the chemical reactions during ALD provides excellent control over the layer thickness. However, in contrast to idealized growth models, it is experimentally challenging to create continuous monolayers by ALD because surface inhomogeneities and precursor steric interactions result in island growth during film nucleation. Thus, the ability to create pin-hole free monolayers by ALD would offer new opportunities for controlling interfacial charge and mass transport in semiconductor devices, as well as for tailoring surface chemistry. Here, we report full encapsulation of c-plane gallium nitride (GaN) with an ultimately thin (~3 Å) aluminum oxide (AlOx) monolayer, which is enabled by the partial conversion of the GaN surface oxide into AlOx using a combination of trimethylaluminum deposition and hydrogen plasma exposure. Introduction of monolayer AlOx significantly modifies the physical and chemical properties of the surface, decreasing the work function and introducing new chemical reactivity to the GaN surface. This tunable interfacial chemistry is highlighted by the reactivity of the modified surface with phosphonic acids under standard conditions, which results in self-assembled monolayers with densities approaching the theoretical limit. More broadly, the presented monolayer AlOx deposition scheme can be extended to other dielectrics and III-V-based semiconductors, with significant relevance for applications in optoelectronics, chemical sensing, and (photo)electrocatalysis.

机构、总结、中文摘要均由AI分析而来,可能存在错误,请以论文正文为准。

↑