磁控溅射不同厚度银膜的微结构及其光学常数

Microstructure and optical constants of sputtered Ag films of different thickness

用直流溅射法在室温K9玻璃基底上制备了8.2nm—107.2nm范围内不同厚度的Ag薄膜,并用X射线衍射及计算机辅助优化程序对薄膜的微结构和光学常数进行了测试分析.结构分析表明制备的Ag薄膜均呈多晶状态,晶体结构均呈面心立方;随着膜厚的增加,薄膜的平均晶粒尺寸逐渐增大,晶面间距逐渐减小.计算机辅助优化编程计算的薄膜光学常数分析表明在波长550nm处,当膜厚小于17.5nm时,随着膜厚的增加,折射率n快速减小,消光系数k则快速增大;当膜厚大于17.5nm时,n和k逐渐趋于稳定.

Ag films with different thickness from 8.2nm to 107.2nm were prepared by DC sputtering deposition and analyzed by X-ray diffraction with the help of optimization program on computer. Microstructrue analysis shows that the films are made of fcc-Ag particles. With the increase of thickness, the mean size of Ag particles increases and the interplaner spacing decreases gradually. The optical constants computed by computer program shows that n value decreases quickly with the increasing thickness below 17.5nm and k value changes in reverse, and then go steadily when the thickness is larger than 17.5nm at the wavelength of 550nm.