IBAD钼膜与Al_2O_3(0001)单晶界面的HREM研究

INESTIGATION OF IBAD Mo FILMS-Al_2O_3(0001) SUBSTRATE INTERFACES BY HIGH RESOLUTION MICROSCOPY

采用中等能量离子束辅助沉积（IBAD）技术在单晶Al2O3（0001）基片上沉积钼膜，通过HREM等分析手段，在原子尺度上，对于钼膜及其与Al2O3单晶基体界面的显微结构进行了研究。结果表明：钼膜的晶粒呈细小柱状或纤维状，平均晶粒尺寸约为8nm，钼膜的致密度较高，膜内存在非晶组织。在钼膜与Al2O3单晶基片之间存在厚约10～15nm的非晶过渡层，在界面处未发现原子的长程扩散。非晶过渡层与钼膜界面处存在台阶，增加了钼膜的形核点。

Molybdenum films were deposited on Al2O3(0001) substrate by ion-beam assisted deposition (IBAD). The microstructure of the films and the interface between molybdenum films and Al2O3 (0001 ) have been studied on atomic scale by using the cross-sectional technique and HREM. The results show that molybdenum films deposited by IBAD result in a columnar microstructure with columns which are uniform in width from substrate to the top of the films. The average column diameter is about 8 nm. No voids were found in the column boundaries. An amorphous intermediate layer of 10~15 nm in thickness at the interface was observed. The interface between the intermediate layer and molybdenum is atomically fat and in direct contact.Molybdenum film can nucleate directly either on the intermediate amorphous layer or at the steps of about 2 nm deep. No long range diffusion of atoms were detected in the interface.