The bi-material strip bending (BMSB) experiment is successfully employed to monitor in situ, the evolution of residual stresses during curing and thermal cycles of epoxy resins, including neat epoxy, silica-modified and rubber-modified epoxies. In the BMSB experiment, the curvature changes of a bi-material strip specimen consisting of a resin film applied onto a glass slide during a temperature excursion is measured in situ within a temperature chamber. The changes in viscosity and curing kinetics of the resins with temperature are also characterized, which are correlated to the residual stress evolution. Based on the constitutive relation between the residual stress and the elastic modulus change with temperature, the coefficients of thermal expansion of the resins are also determined, which are compared with those obtained from the thermo-mechanical analysis. The resins are also subjected to repeated heating and cooling to study the changes in residual stress due to thermal cycles often encountered in reliability tests of electronic packages. (C) 2004 Elsevier Ltd. All rights reserved.