In Pecvd Preparation Of Silicon-based Sio <sub> 2 </ Sub> Waveguide Film Material

With the development of optical communication, more attention has been paid to silicon-based optical waveguides. Silicon-based silica optical waveguides have many excellent advantages such as simple structure and low loss, further more they are good materials for integrated optics and have good match with optical fibers. Integrated devices on silicon-based silica planar optical waveguides have been widely used and play a more important role in optical communications. Integrated silica waveguides with well defined core shapes provide an efficient means of controlling both the amplitude and phase of optical signals, are widely used in production of Mach-Zender optical interferometer, optical splitters, AWG, thermooptic switches and various kinds of filters.Depositing high quality SiO₂ films on Si substrates are the basis for fabricating waveguides and integrated devices. Some fabrication methods of thick SiO₂ film are described, and the advantages of fabricating SiO₂ films for optical waveguides by plasma enhanced chemical vapor deposition (PECVD) methods are discussed. The theory and structure of PECVD system are introduced, SiO₂ films with different parameters are deposited on Si substrates.The surface morphology and root-mean-square surface roughness of the SiO₂ films are characterized by scanning electron microscopy (SEM) and atomic force microscopy (AFM). The compositional properties of the SiO₂ films are analyzed by X-ray photoelectron spectroscopy (XPS). The effects of experiment parameters are discussed.