Influence of silver nanoparticle surface coverage on optical absorption properties of amorphous silicon thin film

Silver nanoparticles with different surface coverages were deposited on amorphous silicon thin film surfaces using magnetron sputtering. The influence of nanoparticle surface coverage on the optical absorption properties of amorphous silicon thin film was investigated. The results show that the lattice structure of thin film is not affected with the increase of nanoparticle surface coverage. However, with the surface coverage increasing, the optical absorption coefficient of the thin film changes obviously in the near-infrared region. When the nanoparticle surface coverage increases to 8%, the maximum optical absorption coefficient of the thin film is reached in the near-infrared region. It is mainly due to the enhancement of optical absorption via localized surface plasmon in nanoparticles.