Optical and morphological properties of silicon dioxide thin films

The purpose of the present work is to compare the structural and optical properties of the Silicon dioxide films obtained from TMOS Si(OCH₃)₄), N₂O, and NH₃ as precursor gases, which with respect to their potential optical applications, have been deposited by using inductively coupled plasma-enhanced chemical-vapor deposition method. The optical property as well as the thickness of the films were analyzed by means of variable angle spectroscopic ellipsometry. Morphological studies were carried out by scanning electron microscopy, and chemical composition characterization was performed with the help of energy dispersive spectroscopy unit coupled with the electron microscope. The type of the substance and the precursor composition used for silicon dioxide synthesis are effective on the chemical composition of the films. The refractive index values of these films advocate their use as high refractive index materials while their low extinction coefficients assure the devices transparency. The work presents deposition rates as well as the films optical properties, chemical composition and morphology regarding the operational parameters of their synthesis. It also provides a comparison of the characteristics of the two competitive precursor compounds.