Effects of PS-PVP diblock copolymer topography on the magnetic properties of CoCrPt thin films

Abstract

The magnetic properties and growth structure of Co68Cr18Pt14 thin films deposited on self-assembled PS21400 (styrene) -PVP20700 (4-vinyl pyridine) diblock copolymer surfaces were investigated using a magneto-optical microscope magnetometer (MOMM). The perpendicular magnetic anisotropy as well as the coercivity of 200 Angstrom CoCrPt/PS-PVP/Si(100) films in comparison with 200 Angstrom CoCrPr/Si(100) were distinctly enhanced. An atomic force microscope (AFM) revealed that the enhanced perpendicular magnetic anisotropy and coercivity in CoCrPt/PS-PVP/Si(100) films might be ascribed to the reduction of the magnetic dipolar anisotropy of CoCrPt films having a rough surface arising from spherically modulated PS-PVP surface morphology and preferential deposition of CoCrPt on top of the PVP block. (C) 2004 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.