The Annealing Effect on Optical Properties of Silver Copper Alloy Films

In this paper, the dielectric functions of Ag-30.3at.%Cu alloy films upon the annealing effect were investigated by variable angle spectroscopy ellipsometry (VASE). The silver copper alloy films were deposited onto p-type silicon (100) substrate by direct current (DC) magnetron sputtering. With the increase of annealing temperature from 100 °C to 300 °C, the image part of the permittivity for Ag-30.3at.%Cu is significantly decreased in the wavelength below ~500 nm. The structure and surface topography of the alloy films were characterized using high resolution scanning electron microscopy (HR-SEM) and X-ray diffraction (XRD). The effective medium theory (EMA) has been utilized for the treating of surface roughness. The dielectric functions can be manipulated by changing the annealing temperature. Key words: Dielectric functions; silver copper alloy films; magnetron sputtering