Technische Universität Wien
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nanoIR - mid-infrared spectroscopy with nanoscale spatial resolution

The Lendl group operates two nanoIR instruments, a nanoIR 1 and the cutting edge nanoIR 3s (both Bruker). These instruments are scanning probe microscopes optimized for nearfield optical spectroscopy using photothermal induced resonance (PTIR, also called AFM-IR).

PTIR measures the local optical absorption via the thermal expansion of the sample to achieve lateral spatial resolution below the diffraction limit (~20 nm). The instruments are coupled to a pulsed mid-infrared laser ultra high resolution AFM-IR nearfield spectra can be directly compared to conventional FTIR transmission or ATR spectra. This allows to perform chemical analysis at the nanometer scale.

In addition to IR characterization, the nanoIR system also provides AFM topography images. When using the scanning Joule expansion (SJEM) mode, local resisitive heating in circuits and devices can be quantified.

For a theoretical background information and applications see here.

nanoIR 3s



nanoIR 3s is BRUKER's latest nanoscale IR instrument. It uses a top illumination geometry for highest flexibility in sample geometry. In addition to photothermal nearfield spectroscopy it is also equipped with scattering scanning nearfield optical microscopy (s-SNOM) unit for high resolution nearfield reflection spectroscopy (advantageous for samples with low thermal expansion).



nanoIR 1

The nanoIR 1 uses bottom illumination mode. This concentrates the light at the substrate-sample interface. Currently, we are exploring the use of this illumination mode for imaging live micro-organisms in water (or aqueous media).

Performance Specs

spatial resolution IR 20 nm
spatial resolution AFM < 1 nm
scan range AFM (x,y) 50 µm
scan range AFM (z)5 µm
spectral coverage890 - 1750 cm-1 & 2750 - 2930 cm-1
maximum sample size (x,y)

~ 10 mm