Fe-ZnO(000)体系的界面化学作用及表面形貌  

Interfacial chemical reactions and surface morphology of Fe-ZnO(000) system

作　　者：张旺[1] 张文华[1] 王国栋[1] 李宗木[1] 徐法强[1] 

机构地区：[1]中国科学技术大学国家同步辐射实验室,安徽合肥230029

出　　处：《中国科学技术大学学报》2007年第4期554-559,共6页JUSTC

基　　金：国家自然科学基金(10505019)资助

摘　　要：采用同步辐射光电子能谱、原子力显微镜及场发射扫描电镜等技术研究了3 nm Fe薄膜在极性ZnO(000)表面的沉积和退火过程中的界面化学过程.结果表明:在低覆盖度下,Fe价层电子与极性ZnO表面间存在较强电子迁移作用;当覆盖度超过1个原子层后,Fe与ZnO的反应在热力学上被禁阻;室温下Fe在表面形成直径约为20 nm的岛状结构,通过对样品退火处理,发现Fe-ZnO在600℃时开始发生强烈作用,形成Fe的氧化态峰,并于800℃完全转换为Fe2+,随着退火温度的继续提高,Fe有继续向Fe3+转变的趋势,并在ZnO表面形成直径120 nm左右的氧化物岛结构.Synchrotron radiation photoemission spectroscopy （SR-PES）, atom force microscopy （AFM） and field emission scanning electron microscope were used to study the chemical reactions between iron and O-terminated polar ZnO（0001^-） surface during the interface formation and annealing process. For iron coverages below 1 ML, Fe^2＋ species are formed at Fe/ZnO interface, followed by the formation of a metallic iron overlayer. The bonding of Fe at very low coverages occurs by electron transfer from Fe to surface oxygen atoms. The thermal stability of the interface was also studied from room temperature to 900 ℃. The results that the iron is oxidized into Fe^2＋ species at 600 ℃, and it tends to be oxidized into Fe^3＋ species at even higher temperatures. The room temperature deposited 3 nm Fe deposition forms 3D islands of about 20 nm in diameter on the surface. And it changes rapidly to 120 nm in diameter as the annealing temperature increases to 900 ℃.

关 键 词：分子束外延 Fe-ZnO(0001^-)界面 同步辐射光电子能谱 X光电子能谱 原子力显微镜 场发射扫描电镜 

分 类 号：O484.11[理学—固体物理]