Growth and Characterization of Silicon-Based Dielectrics using Plasma Enhanced Chemical Vapor Deposition

Plasma Enhanced Chemical Vapor Deposition (PECVD) is widely used in industry for its low temperature growth capability, excellent conformity (step coverage) and higher deposition rates.Silicon dioxide (SiO 2 ), silicon nitride (Si 3 N 4 ) and silicon oxynitride (SiO x N y ) are common dielectrics deposited using PECVD and they will be the main focus of this thesis.These common dielectrics are used in a range of different applications, from optical waveguides to photovoltaic passivation layers and from transistor fabrication to micro electromechanical systems (MEMS) devices.PECVD system parameters (temperature, pressure, power, and gas ratio) are methodically varied and the resulting thin films are characterized.This requires many different metrology techniques such as: atomic force microscopy (AFM), ellipsometry, X-ray diffraction (XRD) and energy dispersive X-ray spectroscopy (EDS).Optical and structural properties of the resulting thin films are analyzed via a careful design of experiments to determine which system parameter has the most significant effect and to which extent they can be varied.