Effect of the Synthesis Temperature on the Optical Indices of Organic Materials Produced by N2-CH4 RF Plasma

摘要

A RF CCP plasma discharge in N-2/CH4 mixture is used to produce organic films. Here is presented the influence of a cryogenic cooling during the film synthesis on the optical refractive indices. The optical indices in the visible range are determined by spectroscopic ellipsometry. It is shown that the optical absorption is lower for a material produced at low temperature (105K) than at room temperature. The absorption decrease is assigned to nitrogen containing products depletion confirmed both by IR absorption spectroscopy of the film on the one hand and by mass spectrometry of the reactive gas phase on the other hand.