Patterning of templated-confined nanoscale Au films by thermal-induced dewetting process of a PMMA underlaying layer

In this work we propose a new approach to prepare surface micro-patterns in nanoscale deposited Au films. In particular, we exploit the idea to use a template confined dewetting aging not directly on the deposited Au film but on an underlaying poly(methylmethacrylate) (PMMA) substrate by thermal processes. The idea consists of the following basic concepts: (a) to perform nanoscale Au film deposition assisted by micrometric templates to obtain a template confined film, and (b) by low-temperature thermal processes (<400 °C) to induce a dewetting process of the PMMA to guide specific patterning effects in the top nanoscale Au film. In this approach, the Au surface pattern order is established by the template confined deposition on a micrometric scale (which is a highly efficient way to synthesize metallic surface patterns with controllable structures, large pattern areas, and to achieve a high throughput), while the realization and control of the Au surface pattern is given by the control of the dewetting process of the underlaying substrate, without invoking high temperature thermal processes. We illustrate experimental results of such an approach and we propose it as a model methodology for surface large scale micro-patterning of nanoscale metal films which can be applied to a wide range of systems towards device applications (i. e. plasmonics).