7 research outputs found
Thin Film Analysis by Nanomechanical Infrared Spectroscopy
There
is a fundamental need for techniques for thin film characterization.
The current options for obtaining infrared (IR) spectra typically
suffer from low signal-to-noise-ratios (SNRs) for sample thicknesses
confined to a few nanometers. We present nanomechanical infrared spectroscopy
(NAM-IR), which enables the measurement of a complete infrared fingerprint
of a polyvinylpyrrolidone (PVP) layer as thin as 20 nm with an SNR
of 307. Based on the characterization of the given NAM-IR setup, a
minimum film thickness of only 160 pm of PVP can be analyzed with
an SNR of 2. Compared to a conventional attenuated total reflectance
Fourier transform infrared spectroscopy (ATR-FTIR) system, NAM-IR
yields an SNR that is 43 times larger for a 20 nm-thick PVP layer
and requires only a fraction of the acquisition time. These results
pave the way for NAM-IR as a highly sensitive, fast, and practical
tool for IR analysis of polymer thin films