Room-temperature InGaAs camera for NIR imaging

Abstract
A room temperature camera based on a 128 X 128 pixel InGaAs focal plane array (FPA) is described. The photodiode array (PDA) was a backside-illuminated device with an In.53Ga.47As epitaxial active layer deposited on an InP substrate. The PDA was bump- bonded to a silicon CMOS readout multiplexer. The FPA was sensitive from below 0.9 micrometers (the cutoff of the substrate) to 1.7 micrometers (the bandgap of the active layer). At room temperature, the mean detectivity of the FPA, D*(lambda pk), exceeded 1013 cm-(root)Hz/W and increased to 3.5 X 1014 cm-(root)Hz/W when cooled to 230 K. Potential applications for this wavelength band are discussed.