AURA (PDS)

AURA is the first commercially available and fully integrated Photothermal Deflection Spectrometer (PDS) that is specifically targeted at R&D in the field of thin films and devices such as solar cells, optical coatings, LEDs, and novel materials. It measures photo-absorption spectra with unparalleled dynamic range and ultra-high sensitivity down to 0.001%, complete with surface selectivity that minimizes masking by substrate absorption. In comparison, common reflection-transmission (R&T) based absorption spectrometers can only reliably measure down to 0.5%.

In addition to the overall higher sensitivity, the PDS technique is most sensitive to the first micrometres of material and less sensitive to the substrate. PDS is the most sensitive and versatile technique for characterising absorption in thin films presently available.

Application Fields

  • Semiconductor defects
  • Quality control
  • Novel absorber materials
  • Absorption dynamics of planar and textured surfaces
  • Contaminant tracing & identifying of non-radiative defects
  • External Quantum Efficiency (EQE)

Features

  • Photo-absorption spectra with up to 5 orders of magnitude dynamic range
  • Easy alignment-free sample mounting
  • Seamless automated measurement from 250 to 2500 nm, with optional IR extension
  • Able to measure absorption on extremely rough surfaces
  • Small measurement spot of 5.5 x 0.75mm
  • Double-monochromator light source for high spectral contrast
  • Intelligent adaptive acquisition minimizes measurement time
  • No detector changeovers to cause spectral artefacts
  • Built-in vibration and acoustic isolation

Example Spectra

The photo absorption spectra of a single crystal 2D perovskite film (1) was measured. The black curve represents the data of a leading UV-Vis spectrometer (reflectance-&-transmission mode) and the blue curve is from our AURA system. Thanks to the superior sensitivity of the AURA system, deeper sub-bandgap information are clearly visible. It shall be noted that the sensitivity limit of the AURA system was not reached.

(1) Samples were kindly provided by: Dr. A. Mahboubi-Soufiani (UNSW) and Y. Zhang (UQ)