Effective surface passivation of type-II InAsGaSb superlattice photodiodes with cutoff wavelengths in the long-wavelength infrared is presented. A stable passivation layer, the electrical properties of which do not change as a function of the ambient environment nor time, has been prepared by a solvent-based surface preparation, vacuum desorption, and the application of an insulating polyimide layer. Passivated photodiodes, with dimensions ranging from 400×400 to 25×25 μ m2, with a cutoff wavelength of ∼11 μm, exhibited near bulk-limited R0 A values of ∼12 cm2, surface resistivities in excess of 104 cm, and very uniform current-voltage behavior at 77 K.
ASJC Scopus subject areas
- Physics and Astronomy (miscellaneous)