Internal stress and yield strength of copper films on substrates
附着铜膜的内应力及屈服强度

Internal stress and yield strength of pure copper films on substrates were characterized by X-ray diffraction and thermal-cycle substrate curvature methods. The internal stress was of tension, and decreased with increasing working-gas (argon) pressure and increased with increasing film thickness. Tensile yield strength of copper film on steel substrate was reciprocal to the film thickness. Similarly, the compressive yield strength depended strongly on the film thickness, the thinner the film thickness, the larger the compressive yield strength.