In-situ study of transport, magnetic and structural study of cobalt during deposition on PMMA polymer

Abstract

In-situ Resistivity, MOKE and XRR measurement has been performed to measure variation of transport, magnetic properties and structural study respectively with Cobalt (Co) film thickness on Poly (methyl methacrylate) (PMMA) thin films. PMMA films were deposited by Spin coating technique. Cobalt thin films were deposited on PMMA using electron beam evaporation technique. It is observed from resistivity measurement that percolation takes place at around 28 Å Co film thickness. Interestingly magnetic dead layer thickness, calculated from MOKE measurement, is 27 Å. In-situ X-ray reflectivity measurement has been done from PMMA and Co/PMMA thin films to characterize structural details. X-ray reflectivity of Co/PMMA reveals that some Co atoms penetrate 25 Å depth intoPMMA at the interface of Co/PMMA which is interestingly same about magnetic dead layer thickness. This kind of behavior implies the magnetic dead layer occurs due to the intermixing of Co into PMMA layer at interface.