Structure and Electrical Characteristics of Zinc Oxide Thin Films Grown on Si (111) by Metal-organic Chemical Vapor Deposition

摘要

ZnO thin films were grown on Si(111) substrates by low-pressure metal-organic chemical vapor deposition.The crystal structures and electrical properties of as-grown sample were investigated by scanning electron microscopy(SEM) and conductive atomic force microscopy(C-AFM).It can be seen that with increasing growth temperature,the surface morphology of ZnO thin films changed from flake-like to cobblestones-like structure.The current maps were simultaneously recorded with the topography,which was gained by C-AFM contact mode.Conductivity for the off-axis facet planes presented on ZnO grains enhanced.Measurement results indicate that the off-axis facet planes were more electrically active than the c-plane of ZnO flakes or particles probably due to lower Schottky barrier height of the off-axis facet planes.