Guziewicz Elzbieta, Mishra Sushma, Amati Matteo, Gregoratti Luca, Volnianska Oksana
Institute of Physics, Polish Academy of Sciences, 02-668 Warsaw, Poland.
Elettra-Sincrotrone Trieste S.C.p.A., SS 14-km Basovizza, 34149 Trieste, Italy.
Nanomaterials (Basel). 2024 Dec 27;15(1):30. doi: 10.3390/nano15010030.
A Scanning Photoelectron Microscopy (SPEM) experiment has been applied to ZnO:N films deposited by Atomic Layer Deposition (ALD) under O-rich conditions and post-growth annealed in oxygen at 800 °C. spatial resolution (130 nm) allows for probing the electronic structure of single column of growth. The samples were cleaved under ultra-high vacuum (UHV) conditions to open atomically clean cross-sectional areas for SPEM experiment. It has been shown that different columns reveal considerably different shape of the valence band (VB) photoemission spectra and that some of them are shifted towards the bandgap. The shift of the VB maximum, which is associated with hybridization with acceptor states, was found to be correlated with carbon content measured as a relative intensity of the C1s and Zn3d core levels. Generalized Gradient Approximation (GGA) supplemented by +U correction was applied to both Zn3d and O2p orbitals for calculation of the VZn migration properties by the Nudged Elastic Band (NEB) method. The results suggest that interstitial -CHx groups facilitate the formation of acceptor complexes due to additional lattice perturbation.
扫描光电子显微镜（SPEM）实验已应用于在富氧条件下通过原子层沉积（ALD）沉积并在800°C氧气中进行生长后退火的ZnO:N薄膜。空间分辨率（130 nm）使得能够探测单生长柱的电子结构。在超高真空（UHV）条件下对样品进行劈裂，以开辟用于SPEM实验的原子级清洁横截面区域。结果表明，不同的生长柱显示出明显不同的价带（VB）光发射光谱形状，并且其中一些向带隙移动。发现与受主态杂化相关的VB最大值的移动与以C1s和Zn3d核心能级的相对强度测量的碳含量相关。通过推挤弹性带（NEB）方法，对Zn3d和O2p轨道都应用了补充有+U校正的广义梯度近似（GGA）来计算VZn迁移特性。结果表明，间隙-CHx基团由于额外的晶格扰动而促进了受主络合物的形成。
