Options
Extending Stoney's equation to thin, elastically anisotropic substrates and bilayer films
Date Issued
01-01-2016
Author(s)
Injeti, Sai Sharan
Indian Institute of Technology, Madras
Abstract
The Stoney equation has been a powerful tool for the thin film community to measure the residual stresses induced in a film through the measurement of curvature of a film-substrate system. Two of the main assumptions of the original Stoney equation are that the substrate is much thicker than the film and its material is isotropic in nature. However, inmajority of the caseswhere the film stress is measured fromthe systemcurvature, Siwafers are used as substrates, which are anisotropic in nature. The anisotropic substrate problem was solved by Nix [1] for thick substrates. In this paper, a modified version of the Stoney equation is derived for configurationswith thin anisotropic substrates, specifically for the cases of Si(001) and Si(111) wafers. The same methodology is then used to extend the Stoney formula to systems with bilayer films on thin substrates.
Volume
598