In Situ Stress, Elastic Constant, Oxygen Surface Exchange Coefficient, and Thermo-Chemical Expansion Coefficient Measurements on Praseodymium Doped Ceria Thin Films

A Multi-beam Optical Stress Sensor provides a noncontact, in situ method for measuring thin film stress based on the curvature of a multilayer sample. Originally, this technique was used to measure film stresses during thin film deposition. However, as demonstrated here using praseodymium doped ceria, when combined with an optically accessible tube furnace, wafer curvature measurements can be used as an in situ, electrode-free platform for measuring film stress, biaxial modulus, thermal expansion coefficient, chemical expansion coefficient, and oxygen surface exchange coefficient.