Fiducial mark and CTOA estimates of thin film adhesion

摘要

Carbon fiducial marks are formed during thin film local delamination processes induced either by superlayer indentation forming circular blisters, or by residual stress relief through telephone cord blister formations. Hydrocarbons are sucked into the crack tip during the delamination process, outlining the crack tip opening angle (CTOA), which can be used to back calculate thin film adhesion using either elastic or plastic analysis presented here. Fiducial marks have been observed in two different thin films systems, namely Cu/SiO_2 and TiW_XN_Y/GaAs. TiW_XN_Y/GaAs system also exhibited biaxial compressive stress-induced phone cord buckling delaminations. Surface AFM CTOA measurement approach is used to estimate the strain energy release rate increase along these phone cords delaminations.