Controlled field evaporation of organic materials has been a long-term challenge for 3-dimensional (3D) atom probe tomography (APT) [1]. Complications arising from sample electrical/thermal requirements, sample preparation methodologies, and hardware configurations have all conspired to limit APT application for this class of materials. Although polymer laser APT studies have been reported on various polymers including polystyrene [2], polypyrrole [2], and polythiophene [3], these reports have focused on field ionized mass spectroscopy (FIMS) of the polymer and have not even attempted 3D reconstructions. We present data on laser local electrode atom probe (LEAP) [4] investigations of alkanethiol self-assembled monolayers (SAMs) and poly-3-alkylthiophenes (P3ATs). Alkanethiols represent an opportunity to understand APT field ionization and reconstruction issues, as applied to polymers, at their most basic level. Alkanethiols are monodisperse short-chain molecules which are covalently bonded to a pre-sharpened metal specimen to form a dense, well-ordered SAM on the tip surface. The well understood microstructure [5] and limited potential for molecular fragment permutations of alkanethiols provides a desirable set of well-defined boundaries for subsequent analyses.
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