Highly c-Axis Oriented ZnO Thin Films Grown by Sol-Gel Method for SAW Sensor Application

摘要

Highly transparent and c-axis oriented ZnO thin films were fabricated by sol gel spin coating method on quartz and Si(100) substrates. The influence of substrates on optical, structural and surface morphological properties has been carried out. The X-ray diffraction patterns reveal that the growth of ZnO thin films along c-axis with crystallite size in the range of 22-33 nm. High percentage transmittance ～90% was observed in the visible region of solar spectrum and optical band gap of thin film estimated to be 3.29 eV. The photoluminescence spectra showed that ZnO thin film fabricated on Si(100) has high intense UV emission peak compared to the film deposited on quartz. The structural property of thin films has been further investigated by Raman spectroscopy. The Raman spectra of thin films showed the crystalline structure with the high intense peak centered at 439 cm~(-1) on both the substrates.