Development of a novel surface elemental analysis methodology: X-ray-aided noncontact atomic force microscopy (XANAM)

Abstract

Scanning probe microscopy (SPM) is widely used for analysis of structures on substrate surfaces. Particularly, scanning tunneling microscopy (STM) and noncontact atomic force microscopy (NC-AFM) enable real-space observations of solid surfaces at the atomic level with high spatial resolution. However, these microscopic measurement methods still involve difficulties in elemental analysis at the nanoscale for general purposes, although several validated solutions have already been proposed for well-defined cases. This brief review explains issues and their resolution, including topics related to the development of chemical analysis methodologies based on STM/NC-AFM, such as inelastic tunneling spectroscopy (IETS)-STM for spectroscopy of individual molecules, STM combined with synchrotron radiation X-ray sources for elemental analysis of surface structures, and force spectroscopy with atom tracking technology, as well as X-ray-aided noncontact atomic force microscopy (XANAM). Particularly, the review describes details of XANAM including recently obtained results on X-ray energy dependence of force spectroscopy and its two-dimensional recording as XANAM imaging, suggesting XANAM offers great potential to contribute to nanoscale investigations of chemical analysis for various purposes.