Characterization of Silicon Nitride and Silicon Carbonitride Layers from 1,1,3,3,5,5‐Hexamethylcyclotrisilazane Plasmas

Abstract

Material properties of silicon nitride films deposited from dilute 1,1,3,3,5,5,‐hexamethylcyclotrisilazane plasmas and silicon carbonitride films deposited from dilute plasmas have been studied. The properties of the two film types differ greatly and are influenced significantly by the ratio of RF power density to the HMCTSZN flow rate . At high , silicon nitride films show good oxidation resistance and display compressive stress. They also possess a high, dielectric strength, dielectric constant, and low fixed charge density. Bias‐temperature stress measurements indicate instabilities related to ionic motion and charge trapping. At low , silicon nitride films contain significant carbon content leading to films that oxidize readily in air. These films have low refractive indexes and exhibit poor dielectric properties. Silicon carbonitride films deposited at high are ceramic‐like, highly oxidation resistant, and have low tensile stress levels. The large spin densities in these films lead to low dielectric strengths and enhanced conductivity. At low , silicon carbonitride films have higher hydrogen content resulting in compressive stresses, lower refractive indexes, and reduced oxidation resistance. Preliminary studies indicate that films deposited from have improved electrical properties compared to or layers.