利用磁控溅射制备了Ag和SiO2分层结构,通过快速热处理,使Ag颗粒扩散到复合薄膜的表面附近.在实验中,通过改变每层Ag和SiO2的厚度,制备出不同形貌的Ag纳米颗粒.分析了Ag颗粒的形貌对其费米能级的影响.发现Ag颗粒的曲率越大,颗粒层间的台阶越宽,颗粒费米能级上的电子数目越多,共振吸收相应地增强.
Ag/SiO2 multilayer thin films were prepared by RF magnetron sputtering. The Ag nanoparticles diffuse towards and mostly assemble near the surface of the Ag-SiO2 films via rapid thermal treat- ment. Ag nanoparticles with different shapes can be obtained by changing the thickness of Ag and SiO2 layers. It is found that the Ag particles with sharper edges and wider terrace between steps have more electrons at Fermi level. Accordingly, the intensity of resonance absorption is obviously enhanced.