Controlling the intrinsic bending of hetero-epitaxial silicon carbide micro-cantilevers

Abstract

We introduce a simple methodology to predict and tailor the intrinsic bending of a cantilever made of a single thin film of hetero-epitaxial silicon carbide grown on silicon. The combination of our novel method for the depth profiling of residual stress with a few nm resolution with finite element modelling allows for the prediction of the bending behaviour with great accuracy. We also demonstrate experimentally that a silicon carbide cantilever made of one distinct film type can be engineered to obtain the desired degree of either upward, flat, or downward bending, by selecting the appropriate thickness and cantilever geometry. A precise control of cantilever bending is crucial for microelectrical mechanical system applications such as micro-actuators, micro-switches, and resonant sensors.