ADHESION IMPROVEMENT AND INTRINSIC STRESS DECREASE IN CERIUM OXIDE THIN-FILMS BY CHOPPING

The effect of chopping on the adhesion and internal stress of cerium o xide thin films and their response to ambient aging are reported here. Chopping increases the adhesion and decreases the stress in the films . The chopped cerium oxide films are able to withstand ambient aging e ffects better than non-chopped films. Both chopped and non-chopped fil ms show a decrease in adhesion and an increase in stress upon exposure to air and humidity and an increase in adhesion on heating. The decre ased stress and increased adhesion due to chopping are discussed in te rms of modification of the wetting characteristics and thereby changes in the morphology of the film. Chopping also seems to enhance the oxy gen affinity of the adatoms. X-ray diffraction results confirm the pre sence of excess oxygen in the chopped film. The chopping technique off ers a low-temperature alternative for obtaining films with adhesion si milar to those deposited on a heated substrate.