| 摘要 |
PURPOSE: A stress measuring method for a multilayered thin film is provided to measure a residual stress with high precision and high reliability by computing the stress on the basis of the equilibrium of forces per a unit length. CONSTITUTION: A stress measuring method for a multilayered thin film includes the steps of measuring a radius of a curvature of a silicon bear wafer, measuring a stressof a final state of the multilayer by a formula 7(σnf=(E/1-υ)siS(t2s/6tf)S((1/Rn)-(1/R0))), and computing a stress of each thin film layer from an equilibrium of forces per a unit length, wherein σf represents a compression stress generated in a film, E represents a coefficient of elasticity of the silicon(1300E9dyn/cm2), υ represents a poission rate of the silicon(0.27), ts represents a value added a thickness of the silicon wafer and a thickness of the whole layers, tf represents a thickness of an evaporated film, R0 represents a radius of curvature of the silicon wafer immediately before the film evaporation, and Rn represents a radius of curvature of the silicon wafer after nth film evaporation.
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