The influence of nitrogen and fluorine on the dielectric constant of hydrogenated amorphous carbon (a-C:H) films

The possibility to use diamond-like carbon (DLC) film as dielectric in CIs has been motivating the study of this material. In this work, an analysis focused on the influence of the nitrogen and fluorine on the dielectric constant of the a-C:H films deposited by a reactive RF magnetron sputtering with a graphite target is reported. Different mixtures (CH4/N2 and CH4/CF4) were used in the depositions. The working pressure process was 5 mTorr and the RF power was 150 W. RBS and FTIR spectra were used to investigate the chemical composition and chemical bonding structure of the films, respectively. As verified in this study, the effect caused by nitrogen and fluorine on the chemical bonding structure of the a-C:H film have a fundamental role on the dielectric constant of this material.