E.S. Kooij, M.A. Raza, B. Poelsema, H.J.W. Zandvliet
Univ. of Twente, MESA+ Inst. Nanotechnology, Netherlands
pp. 321 - 324
Keywords: nanoparticles, selective deposition, patterned metallization
In this contribution we present a novel, simple, low-cost bottom-up method to enable patterned deposition of nanoparticles. Our approach does not require sophisticated equipment nor does it involve harsh chemical procedures. We show that pure water can be used to selectively “defunctionalize” mercaptopropyltrimethoxysilane treated surfaces, therewith inhibiting the binding of metallic gold nanoparticles to these specific areas. We demonstrate that this amazing role of water molecules enables patterning of gold particles on flat as well as on microstructured surfaces with a remarkably high degree of selectivity. In addition to the localized gold nanoparticle deposition, we describe selective metallization by electroless gold deposition on the patterned seed arrays. The latter process gives rise to enlargement of the isolated seeds past the percolation threshold, to ultimately give rise to conducting metal structures. The obtained patterned gold films exhibit macroscopic conductivity values approximately a factor of three lower than that of bulk gold. The surface morphology of the films has been characterized by scanning electron microscopy and spectroscopic ellipsometry. We discuss the different regimes as observed in morphological, electrical and optical characterization in relation to each other.