Less is More: Improved Thermal Stability and Plasmonic Response in Au Films via the Use of SubNanometer Ti Adhesion Layers

• DOI: 10.1021/acsami.8b21193
• Publication Date: 2019-01-25T23:15:15Z
• Authors: William M. Abbott; Christopher P. Mu...; Chuan Zhong; Christopher Smith; Cormac McGuinness; Ehsan Rezvani; Clive Downing; Dermot Daly; Amanda K. Petford...; Frank Bello; David McCloskey; John F. Donegan
• Keywords: Dewetting; Thermal Stability

The use of a metallic adhesion layer is known to increase the thermo-mechanical stability Au thin films against solid-state dewetting, but in turn results damping plasmonic response, reducing their utility applications such as heat-assisted magnetic recording (HAMR). In this work, 50 nm with Ti layers ranging thickness from 0 5 were fabricated, and thermal stability, electrical resistivity, response measured. Subnanometer are demonstrated significantly dewetting at elevated temperatures (>200 °C), compared more commonly used thicknesses that range 2-5 nm. For thicker than 1 nm, diffusion excess through grain boundaries subsequent oxidation was determined result degradation film. This mechanism confirmed using transmission electron microscopy X-ray photoelectron spectroscopy on annealed 0.5 samples. superiority subnanometer further measurements surface-plasmon polariton resonance; those thinner possessed both stronger spectrally sharper resonance. These have relevance beyond HAMR all Ti/Au systems operating temperatures.