Uncooled photodetectors based on CdSe nanocrystals with an interdigital metallization

Uncooled photodetectors fabricated from CdSe nanocrystals with an interdigital metallization are investigated in the visible-near-infrared spectral region. A device with 5 μm interdigital spacing possesses a dark current on the order of 10−11 A while the photocurrent is measured to be five orders of magnitude higher than the dark current. The room temperature detectivity extracted from the photocurrent and dark current is estimated to be on the order of 3.5 x 1010 cmHz1/2 W−1 at 5 V bias voltage. The spectral response was measured with an onset at 710 nm, which is in good agreement with the photoluminescence spectra obtained from the nanocrystals.