nano-FTIR nanoscopy based identification of polymers at the 10nm length scale

Scattering-type Scanning Near-field Optical Microscopy (s-SNOM) employs the strong confinement of light at the apex of a sharp metallic AFM tip to create a nanoscale optical hot-spot. Analyzing the scattered light from the tip enables the extraction of the optical properties below the tip and yields nanoscale resolved images simultaneous to topography [1]. Recently, the technology has been advanced to enable FTIR-spectroscopy on the nanoscale (nano-FTIR) [2].

Applying nano-FITR near-field spectroscopy to measure the spectroscopic signature enables identification of i.e. polymers at a spatial resolution given only by the size of the AFM tip [3]. For example, nano-FTIR spectra of a phase-separated PS/LDPE polymer blend of only 50nm thickness enable to identify the samples polymer materials.

Results presented demonstrate that nano-FTIR can be an ideal analysis method to characterize complex material systems and to identify polymer materials at the nanoscale spatial resolution and unmatched sensitivity.

[1] F. Keilmann, R. Hillenbrand, Phil. Trans. R. Soc. Lond. A 362, 787 (2004).
[2] F. Huth, et al., Nano Lett. 12, 3973 (2012).
[3] I. Amenabar, et al., Nature Commun. 8, 14402 (2017).