High-resolution mapping of infrared photoluminescence

We report preliminary results of high-resolution scanning photoluminescence (PL) experiments in the near- and mid-infrared (IR) portions of the spectrum. The samples investigated were Hg0.7Cd0.3Te epilayers grown on Cd0.96Zn0.04Te and CdTe/Si substrates used in IR detectors and focal-plane arrays. To measure mid-IR PL, we modified a commercial, Fourier transform infrared (FTIR) spectrometer and designed a confocal microscope attachment. For near-IR PL mapping, we used a confocal microscope coupled to a grating spectrometer and a charge-couple device (CCD) camera. Diffraction-limited resolution was achieved in the near-IR setup (0.5 µm) and 22-µm resolution for the mid-IR setup.