13 June 2007 Type-II InAs/GaSb strain layer superlattice detectors for higher operating temperatures
Author Affiliations +
Type-II InAs/GaSb superlattice photodiodes for mid-IR (3-5μm) region grown by solid-source molecular beam epitaxy are reported. Different approaches for realization of high quality interfaces between compositionally abrupt GaSb and InAs layers during the growth of the SLs are discussed. Mid wave infrared (&lgr;c~ 4.5 µm at T=300K) P-on-N designs of SLs detectors were developed to ensure compatibility with most present day readout integrated circuits (ROICs). Variable size diode arrays were fabricated using standard photolithography technique and hybridized to silicon fanout chip. The sizes of the detector mesas were varied from 29μm x 29μm to 804μm x 804μm. The single pixel characterization was undertaken at Santa Barbara Focal Plane. Temperature-dependent IV measurements revealed dark current density below 1 x 10-8 A/cm2 at 82K and below 2 x 10-5 A/cm2 at 240K. (Vbias = 0V). Dynamic resistance-area product at zero bias was found to be ~ 1 x 105 Ωcm2 at 82K and 0.24 Ωcm2 at 240K. Influence of protective silicon nitride coating on reduction surface leakage currents of detectors was investigated. We found that rsurface was equal to ~ 3 x 106 Ωcm indicating the proper surface preparation followed by room temperature Si3N4 deposition is effective in reduction of leakage currents in type-II MWIR InAs/GaSb superlattice photodiodes.
© (2007) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
J. B. Rodriguez, J. B. Rodriguez, E. Plis, E. Plis, S. J. Lee, S. J. Lee, H. Kim, H. Kim, G. Bishop, G. Bishop, Y. D. Sharma, Y. D. Sharma, L. R. Dawson, L. R. Dawson, S. Krishna, S. Krishna, C. Jones, C. Jones, "Type-II InAs/GaSb strain layer superlattice detectors for higher operating temperatures", Proc. SPIE 6542, Infrared Technology and Applications XXXIII, 654208 (13 June 2007); doi: 10.1117/12.720637; https://doi.org/10.1117/12.720637

Back to Top