Performance improvement of InAs/GaSb strained layer superlattice detectors by reducing surface leakage currents with SU-8 passivation

We report on SU-8 passivation for performance improvement of type-II InAs/GaSb strained layer superlattice detectors (lambda(cut-off)similar to 4.6 mu m). Optical and electrical behavior of SU-8 passivated and unpassivated devices was compared. The dark current density was improved by four orders of magnitude for passivated single diodes at 77 K. The zero bias responsivity and detectivity at 77 K was equal to 0.9 A/W and 3.5x10(12) Jones for SU-8 passivated single pixel diodes. FPA size diodes (24x24 mu m(2)) were also fabricated and they showed responsivity and detectivity of 1.3 A/W and 3.5x10(12) Jones, respectively at 77 K.