AFM-IR Laboratory

AFM-IR system (Fig. 1)

Nanoscale Infrared Spectrometer (nanoIR2 system).


Fig. 1. nanoIR2 system.

    NanoIR 2 consists of:

  • Atomic Force Microscope (AFM)
  • Integrated AFM-IR system
  • 2 infrared radiation sources (Fig. 2)


    Parameters:

  • Atomic Force Microscope (AFM):
    • scanner XYZ with a range of 80 x 80 x 7 μm
    • contact mode
    • tapping mode
  • Integrated AFM-IR system:
    • contact mode – AFM-IR spectra, AFM-IR mapping
    • manual selection of series of points in the AFM topography image
    • automatic acquisition of infrared spectra from points or lines marked in the AFM topography
    • absorption mapping of individual wavelengths in the infrared range
    • simultaneous measurement of infrared absorption and mechanical properties of the sample
    • work in enhanced resonance mode by adjusting the pulse repetition frequency of the IR source to the resonance frequency of the AFM probe which is in contact with the material at different places in the sample
  • Infrared radiation sources - tunable lasers emitting radiation of nanosecond pulsed IR:
    • OPO laser (optical parametric oscillator) – spectral range 900 cm-1 – 3600 cm-1
    - solid-state laser - Nd: YAG laser
    - emits beam pulses at a frequency of 1 kHz with a length of 10 ns
    - maximum spectral resolution 4 cm-1
    - minimum sample thickness 100 nm
    - polarization of IR radiation 0º – perpendicular to the sample surface
    - polarization of IR radiation 90º – parallel to the sample surface
    • QCL laser (Quantum Cascade Laser ) – spectral range 1145 cm-1 – 1900 cm-1
    - semiconductor laser
    - tunable frequency in the range: 0.1–500 kHz with a length of 180 ns - adjustment of the laser pulse frequency to the resonance frequency of the AFM probe which is in contact with the investigated material
    - maximum spectral resolution 1 cm-1
    - minimum sample thickness even 10 nm
    - polarization of IR radiation 90º – perpendicular to the sample surface
    - polarization of IR radiation 0º – parallel to the sample surface


Fig. 2. Tunable lasers emitting IR radiation. From the top OPO laser, from the bottom QCL laser.