Closed-loop atomic force microscopy-infrared spectroscopic imaging for nanoscale molecular characterization.

ABSTRACT: Atomic force microscopy-infrared (AFM-IR) spectroscopic imaging offers non-perturbative, molecular contrast for nanoscale characterization. The need to mitigate measurement artifacts and enhance sensitivity, however, requires narrowly-defined and strict sample preparation protocols. This limits reliable and facile characterization; for example, when using common substrates such as Silicon or glass. Here, we demonstrate a closed-loop (CL) piezo controller design for responsivity-corrected AFM-IR imaging. Instead of the usual mode of recording cantilever deflection driven by sample expansion, the principle of our approach is to maintain a zero amplitude harmonic cantilever deflection by CL control of a subsample piezo. We show that the piezo voltage used to maintain a null deflection provide

SUBMITTER: Kenkel S 

PROVIDER: S-EPMC7320136 | biostudies-literature | 2020 Jun

REPOSITORIES: biostudies-literature