Ti缓冲层对ZnO薄膜吸收特性和荧光光谱的影响

Effects of Ti buffer layer on the absorption characteristic and fluorescence spectrum of ZnO films

采用射频磁控溅射法在Si衬底和玻璃衬底上制备了ZnO/Ti薄膜,利用紫外-可见分光光度计和荧光分光光度计等技术表征了ZnO/Ti薄膜的光学特性,研究了Ti缓冲层的厚度对ZnO薄膜的影响。透射吸收光谱显示所有ZnO薄膜在可见光区域的平均透过率超过80%,当引入缓冲层后,薄膜的紫外吸收边先向长波方向移动,且随着缓冲层厚度的增加紫外吸收边向短波方向移动。薄膜的荧光光谱显示,所有样品出现了位于390nm的紫外发光峰,435和487nm的蓝光双峰以及525nm的绿光峰,并对各发光峰的来源进行了探讨。

ZnO films using different thick Ti buffer layers were deposited on Si and glass substrates by radio frequency（RF） reactive magnetron sputtering.The effect of buffer layers on the absorption characteristic and fluorescence spectrum of ZnO films was characterized by ultraviolet-visible spectrophotometer and fluorescence spectrophotometer.The results revealed that all films had an average optical transparency over 80% in the visible range,the UV absorption edge shifted to a longer wavelength after Ti buffer introduced and shifted to a shorter wavelength as the thickness of Ti buffer increased.Three main emission peaks including a UV located at about 390nm,two blue peaks located at about 435 and 487 nm and two green peaks located at about 525 and 560nm were observed from the PL spectra.The origin of these emissions was discussed.