IN-SITU STRESS MEASUREMENTS OF CO PD MULTILAYER FILMS USING AN OPTICAL NONCONTACT DISPLACEMENT DETECTOR/

We have constructed an apparatus for in situ measurement of stress of the film prepared by sputtering using an optical non-contact displacem ent detector. A change of the gap distance between the detector and th e substrate, caused by stress of a deposited film, was detected by a c orresponding change of the reflectivity. The sensitivity of the displa cement detector was 5.9 V Angstrom(-1) and thus it turned out to be go od enough to detect stress caused by deposition of a monatomic layer o f Co or Pd. The apparatus was applied to in situ stress measurements o f Co/Pd multilayer thin films prepared on the glass substrates by d.c. magnetron sputtering. At the very beginning of the deposition, both C o and Pd sublayers exhibited tensile stresses. However, when the film was thicker than about 100 Angstrom, constant tensile stress in the Co sublayer and compressive stress in the Pd sublayer were observed, whi ch is believed to be related to a 9% lattice mismatch between the matc hing planes of Co and Pd.