HgTe and PbS colloidal quantum dots (CQD) with first excitonic absorption peak of about 2 μm
and shorter (down to about 1 μm) have been synthesized and characterized. The synthesized
CQDs were characterized using FTIR spectroscopy and TEM technique. The nanomaterials were
tested for photo-electrical properties with photoconductive (PC) devices. The devices were
fabricated by drop-casting a suspension of the CQDs on the fanout, followed by solid state ligand
exchange (SSLE) process, and then spectral and electrical photoresponse of the device were
measured. The SSLE process was evaluated thru absorption spectra of test samples. The device
fabrication parameters were the number of deposited layers, the thickness of individual layers,
the type of the substituting ligand, and the ligand exchange duration. For selected devices
external quantum efficiency (EQE) was also determined.
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