Atomic-Resolution Surface Imaging under Ambient Conditions via Conductive Atomic Force Microscopy

M.Z. Baykara
University of California, Merced,
United States

Keywords: atomic force microscopy, atomic-resolution imaging, defects, 2D materials

Summary:

Atomic-scale characteristics of surfaces play a central role in numerous scientific fields. Yet, the tools utilized to characterize surfaces with atomic resolution rely on strict environmental conditions such as ultrahigh vacuum, limiting the relevance of results for realistic applications. Here, we report true atomic-resolution imaging via conductive atomic force microscopy (C-AFM) under ambient conditions [1]. Our approach delivers atomic-resolution maps on a variety of material surfaces that comprise defects including single atomic vacancies, at high scanning speeds. Moreover, we report the capability of in situ charge state manipulation of defects on MoS2, and the observation of an exotic electronic effect: room-temperature charge ordering in a thin transition metal carbide (TMC) crystal (i.e., an MXene), α-Mo2C. Our findings herald the emergence of C-AFM as a powerful tool for atomic-resolution imaging and manipulation of surface structure and electronics under ambient conditions, with wide-ranging applicability. [1] S.A. Sumaiya, J. Liu, M.Z. Baykara, ACS Nano 16, 20086 (2022).