Analytic solution of stress distribution under a thin film edge in substrates

We have obtained an analytic solution for the stress distribution under a t hin film edge in isotropic substrates of finite thickness and of infinite e xtent in the other two directions. Far from the film edge on the side witho ut the film, all stress components are zero and far from the film edge unde r the film, the stress distribution is in accordance with that given by the bimetallic strip theory. To demonstrate the validity of this solution, the experimental infrared photoelastic stress fringe pattern obtained by a dar k-field plane polariscope in a Si substrate under an oxide film edge was su ccessfully reproduced using this solution. (C) 2001 American Institute of P hysics.