Patent ID: 7358554

Claim:
A substrate bearing a thin film of a material having a modified in-film stress, said substrate having a predetermined stress wherein said predetermined stress provides a mechanical stress s to said thin film, said mechanical stress being derived using the following equations: s=s i +s T (1) where s i is intrinsic stress calculated by the expression: s i =[E s /6(1− n s )]( d s 2 /d f )(1 /R s −1 /R f ) (2) where E s and n s are Young's modulus and Poisson ratio of said substrate, respectively, d s and d f are thickness of said substrate and said thin film, respectively, and R s and R f are radii of curvature of said substrate without and with said thin film, respectively, and where s T is thermal stress in said thin film calculated by the expression: s T [E f /(1− n f )]( a f −a s )( T d −T M ) (3) where E f and n f are Young's modulus and Poisson ratio for said thin film, respectively, a f and a s are average thermal coefficients of said thin film and said substrate, and T d and T M are film deposition temperature and temperature during stress measurement, respectively.