Micro-Raman Analysis of a Micromachined 3C-SiC Cantilever

Abstract

In this work, Raman microscopy is used to study the stress distribution on 3C-SiC cantilevers. Also we compare the strain distribution observed on the microstructure, using the shift of the transverse optical (TO) mode in micro-Raman maps, with the values predicted using a recent analytic theory [1]. Along the width of the cantilever is observed a reduction of stress ascribed to the etching processes that removes a thin layer of the interface between the 3C-SiC film and the substrate close to the edge of the microstructure. It is possible to show that this variation can be ascribed to a non-linearity of the strain field along the 3C-SiC film thickness. Also, helped by Finite Element Modelling (FEM), we determined the stress tensor along the cantilever. This result shows that, for a complete stress description of the cantilevers, it is necessary taking into account the role of diagonal and off-diagonal stress tensorial components.