Thermal strain measurement in sol-gel lead zirconate titanate thin films

A fluorescence-based digital image correlation (DIC) technique is used to characterize the in-plane strain development of blanket sol-gel derived lead zirconate titanate thin films deposited on platinized silicon substrates. The in-plane strain is also measured within film line features patterned via a mediated octadecyltrichlorosilane (ODS) monolayer. The results indicate that the selective film failure induced by the mediated ODS layer succeeds in slightly reducing the in-plane strain transverse to the line feature direction (⁠$∼25%$ lower), while remaining nearly the same as the blanket film case in the direction parallel to the line direction. Additional in-plane stress estimates from wafer curvature measurements for the two film configurations (blanket and ODS patterned) were consistent with the DIC measured strain results.