ABSTRACT
Deposited dielectric films are widely used in microelectronic and photovoltaic applications. These dielectric films provide electrical insulation between metals, protection from the environment, masks for diffusion processes, and capacitors for active devices. The most important plasma-deposited dielectric is silicon nitride, often referred to as plasma nitride or SiN. Plasma-deposited silicon nitride in microelectronic fabrication is used mainly as a passivation coating over silicon-integrated circuits. Silicon, nitrogen, and hydrogen are the major constituents of plasma-deposited silicon nitride, but low concentrations of other elements are often present as impurities. The refractive index is the most commonly measured property of plasma silicon nitride. The refractive index is measured by ellipsometry or prism coupling and is used to determine the quality and reproducibility of the deposited films. Plasma-deposited silicon dioxide is used mainly as an insulator between conducting layers on silicon circuits. Silicon dioxide films are also deposited by other techniques similar to plasma-assisted depositions.
