Mechanisms of reactive sputtering of titanium nitride and titanium carbide I: Influence of process parameters on film composition

• Published in: Thin solid films 1983-07, Vol.105 (4), p.353-366
• Main Authors: Sundgren, J.-E., Johansson, B.-O., Karlsson, S.-E.
• Format: Article
• Language: English
• ISSN: 0040-6090; 1879-2731
• DOI: 10.1016/0040-6090(83)90318-8

The reactive sputtering of titanium in mixed ArN 2 and ArCH 4 discharges was studied by measuring the compositions of both the deposited films and the layers formed on the target. The sputtering experiments were performed in a diode r.f. sputtering unit and the compositions were determined by means of Auger electron spectroscopy. The results show that the amount of reactive constituents incorporated into the growing films depends on whether a compound has been formed on the target. At low pressures where no such compound is formed, the incorporation of the reactive gas follows an adsorption isotherm similar to the Langmuir adsorption isotherm, and very low values of the sticking probability are observed. At higher pressures species originating from the target determine the composition of the coatings. The important process parameters were found to be the partial pressures of the reactive and inert working gases, the ion current density and the voltage applied to the target.