Metal Microsubstrates on Si(111): Crystallography, Morphology, and Interactions with a Molecular Adsorbate

Abstract

We describe the growth and characterization of 10 nm to 10 micron-scale islands created by depositing Ag onto Si(111) at elevated temperatures. By varying the surface coverage of Ag, we are able to produce and control the distribution of Ag(111) and/or Ag(100) single-crystal islands. These were examined using scanning tunneling microscopy (STM), X-ray diffraction (XRD), helium ion microscopy (HIM), and atomic force microscopy. The formation of 3D islands with orientations of either (111) or (100) was confirmed by STM and XRD analysis. As these islands manifest as tiny single crystals of elemental Ag, they can be ideally used as low-cost or disposable substrates to host molecular architectures; we demonstrate this by comparing absorption and thermal behavior of 1,3,5-benzenetricarboxylic acid molecules on the islands and noting identical behavior and reactivity to experiments performed on Ag single-crystal counterparts. These islands provide an economical and practical method for facilitating molecular adsorption on two distinct microsubstrates at the same time while under identical experimental conditions.