Structural Properties of SiO2 Thin Films

SiO2 is a low-refractive-index film material, which can be used with high-refractive-index materials in the range from ultraviolet to near-infrared.

SiO2 films are widely used in high-reflection films, anti-reflection films, dielectric films, wavelength beam splitters, bandpass filters due to their advantages of stability, amorphous structure, high density, tunable refractive index, and low particle pollution. , polarizers, etc. [1-4].

At present, there are several deposition methods to obtain high-quality SiO2 films: ion beam sputtering deposition technology, ion assisted deposition technology, molecular beam growth method, magnetron sputtering, plasma enhanced chemical vapor deposition, reactive pulsed laser deposition [5] -8] and so on.

Among them, the SiO2 film prepared by ion beam sputtering deposition technique has stable performance and is the most commonly used deposition method.

The structural properties of SiO2 thin films are one of the important properties that have received extensive attention, generally including surface structural properties and microstructural properties.

The surface structure characteristics of SiO2 thin films are mainly characterized by surface topography characteristics. In order to characterize the essential characteristics of the surface, mathematical statistical parameters are used to characterize the lateral and longitudinal information of the surface. The commonly used parameters are the root mean square roughness and the height distribution function of the surface. , surface autocovariance function and surface power spectral density, etc.