Catalytic synthesis of ZnO nanorods on patterned silicon wafer-An optimum material for gas sensor

摘要

ZnO nanorods have been synthesized over etch-patterned Si (110) wafer using annealed silver thin film as growth catalyst. The growth of ZnO nanorods were performed by a two-step process. Initially, the deposition of Zn thin film was done on the annealed silver catalyst film over etch-patterned Si (110) substrate by thermal evaporation, and then annealed at 800 deg C in air. The etching of the patterned Si (110) wafers was carried out by 50 percent aqueous KOH solution. The samples were investigated by optical microscopy, scanning electron microscopy, X-ray diffraction, Raman spectroscopy and room temperature photoluminescence spec-troscopy. 'V shaped grooves with no undercut were formed after etching due to the anisotropic nature of the KOH etchant. The etch-patterned wafer was used to provide larger surface area for ZnO growth by forming 'V'-grooves. This ZnO film may be predicted as a very good material for gas sensor.