摘要
在大气中用STM研究了固相反应生长的CoSi2薄膜表面．在Si（100）晶片上用离子束溅射淀积Co／Ti双层膜，经退火处理完成三元固相反应，生成TiN／CoSi2／Si膜，然后经H2SO4和H2O2溶液腐蚀去除TiN膜层得到均匀平整的厚度约为100nm的CoSi2薄膜．AES，XRD等分析表明所得CoSi2膜层是Si（100）衬底的外延生长膜．STM测量结果显示CoSi2薄膜表面结构致密平整，主要由交替出现的平台和台阶结构组成．平台的平均宽度为9nm，台阶高度为2个原子层厚度，分析表明这是由于Si衬底的晶面切割偏离（100）面引起的．平台表面呈平行台阶方向的相距约1．1nm的条状结构．在平台区域的局部表面观测到有序结构，其排列方向与条状突起方向间呈45°夹角．对CoSi2薄膜进行剥层腐蚀后再用STM观察其图象，结果表明CoSi2膜的纵向生长也是均匀的。
The surfaces of CoSi2 film grown by solid state reaction are investigated byusing STM in air. A flat homogeneous CoSi2 film with the thickness of 100nm was preparedby Co/Ti/Si ternary solid state reaction and annealing. It is identified by AES and XRDthat the CoSi2 film is an epitaxial film of Si (100) substrate. The STM results show that thealternate terrace and step structures appear on the surface of films, The average width ofthe terraces is 9nm and the step is biatomic that could be explained as the misorientation ofSi (100) surface. The atomic stripes with a space of 1.1nm parallel to the step directionhave been observed on the terraces. The local ordered arrangement which have 45°angle tothe atomic stripes direction are found from the high resolution STM images. The resultsafter partially etching show that the film is homogeneous in longitudinal direction.
基金
国家自然科学基金
关键词
硅
半导体薄膜技术
STM
Cobalt compounds
Film preparation
Films
Microstructure
Molecular beam epitaxy
Silicon wafers
