Dependence of nitrogen content and deposition rate on nitrogen pressure and laser parameters in ArF excimer laser deposition of carbon nitride films

Abstract

The effect of N2 pressure and laser fluence on the chemical composition and growth rate of CNx (0.07<x<0.45) films deposited by ArF excimer laser ablation of a graphite target in nitrogen environment is reported. Between 1 and 50Pa the nitrogen content of the films monotonously increases with increasing pressure. Films deposited at various N2 pressures differ not only in their (average) nitrogen but also in their oxygen content. The chemical composition of the films deposited using pulses of fluences between 0.7 and 2Jcm−2 remains the same within experimental error, while in the 2–10Jcm−2 domain the nitrogen incorporation steeply increases. The growth rates vary from 0.003 to 0.56Å/pulse, increasing linearly with fluence and decreasing with increasing pressure in the 0.7−2Jcm−2 fluence domain, while followed by a supralinear dependence on fluence and less sensitivity to N2 pressure at higher fluences. Changes in film porosity account for the striking features reported.