Micro-Raman characterization of stress distribution within free standing mono- and poly-crystalline silicon membranes

Stress measurements were performed in a free standing monocrystalline cantilever and a polycrystalline silicon membrane suspended over a deep cavity, using micro-Raman spectroscopy. These micromechanical structures were fabricated using porous silicon as a sacrificial layer. The results show that the stress varies across the membrane and the cantilever, the level of stress in the latter being lower than in the membrane.