Relaxation of process induced surface stress in amorphous silicon carbide thin films using low energy ion bombardment

Abstract

The surface stress in amorphous silicon carbide (a-SiC) thin films has been modified after processing. We show that low energy argon ion bombardment in an inductively coupled plasma reactor causes relaxation of the induced surface stress. Cantilever beams of variable length (25–150μm) have been fabricated and their deflection profiles have been compared before and after ion bombardment using white light interferometry. Our experiments show that the ion bombardment relaxes the stress gradient of the cantilever beams. Both the duration of plasma exposure as well as the bias voltage contribute to relaxing the stress gradient in the a-SiC thin film.