Effect of Varying Oxidizing and Nitriding Parameters on the Surface of Cr Thin Films

Publisher Website
Google Scholar
Abstract
Reflection electron diffraction, electron microscopy, and ellipsometric techniques have been used to study the effect of various oxide and nitride treatments on the surface of chromium films. Thin films of chromium prepared by evaporation and deposited on glass substrates in 10−6-Torr vacuum were oxidized or nitrided for varying times at 50°C intervals in a 400°–600°C temperature range. In this study a correlation between surface structures of the films and the environment in which they were grown could be made. It was found in wet or dry environments that (1) the stable Cr2O3 formed at all times and temperatures during the oxidizing process, (2) two forms of the nitride were observed—the fcc CrN and the hexagonal βCr2N both always in combination with Cr2O3, (3) CrN was detected at a temperature of 450°C, (4) at temperatures above 450°C βCr2N was found and the CrN phase disappeared, (5) an increase in time at all temperatures resulted in grain growth of all compounds. Data obtained for varying conditions were used to estimate the activation energy of oxide and nitride formation on these films. The average values were found to be E = 23 kcal/mole for the oxide and E = 15 kcal/mole for the nitride. In general the oxide and nitride compound formation on the Cr film surfaces followed a parabolic rate law, but the rates were faster than those reported for the bulk.

This publication has 0 references indexed in Scilit: