Dynamic in situ optical and magneto-optical monitoring of the growth of Co-Pd multilayers

In situ ellipsometry and Kerr polarimetry have been used to follow the cont inuous evolution of the optical and magneto-optical properties of multiple layers of Co and Pd during their growth. Films were sputter deposited onto a Pd buffer layer on glass substrates up to a maximum of N = 10 bi-layer pe riods according to the scheme glass/Pd(10)Ar x (0.3Co/3Pd) (nm). Magnetic h ysteresis measurements taken during the deposition consistently showed stro ng perpendicular anisotropy at all stages of film growth following the depo sition of a single monolayer of Co. Magneto-optic signals associated with t he normal-incidence polar Kerr effect indicated strong polarization of Pd a toms at both Co-Pd and Pd-Co interfaces and that the magnitude of the compl ex magneto-optic Voigt parameter and the magnetic moment of the Pd decrease exponentially with distance from the interface with a decay constant of 1. 1 nm(-1). Theoretical simulations have provided an understanding of the obs ervations and allow the determination of the ultrathin-film values of the e lements of the skew-symmetric permittivity tensor that describe the optical and magneto-optical properties for both CO and Pd. Detailed structure in t he observed Kerr ellipticity shows distinct Pd-thickness-dependent oscillat ions with a spatial period of about 1.6 nm that are believed to be associat ed with quantum well levels in the growing Pd layer.