Micro-Cantilevers for Thin Films: Young’s Modulus
A simple and effective characterisation technique based on micro-cantilever beams for thin film materials using commonly available equipment — scanning surface profiler — is described. The advantages of this class of techniques are simplicity, speed, cost and a wide applicability. A technique for extracting the Young’s modulus from static deflection data is developed and validated in experiments on thin film specimens of silicon nitride deposited on a silicon substrate under different conditions. Finite element analysis is used to assess the influence of factors affecting the bending of thin films, and thus guide the analysis of micro-cantilever deflection data for reliable characterisation of the material.
Key wordsMEMS materials thin films cantilevers scanning surface profiler finite element methods elastic modulus
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