Conformal Multilayered Passivation for Type-II indium arsenide/gallium antimonide Superlattice Mesas

Period of Performance: 10/31/2016 - 04/30/2019


Phase 2 SBIR

Recipient Firm

Radiation Monitoring Devices, Inc.
44 Hunt Street Array
Watertown, MA 02472
Firm POC
Principal Investigator


The unique electronic properties of periodically-arranged indium arsenide/gallium antimonide (InAs/GaSb) mesas in the type-II strained layer superlattices (SLS) make them a superior alternative to the conventional HgCdTe sensors for longwave infrared focal plane array (LWIR FPA) detectors. However, despite the highly promising quantum structures of SLS, its performance is currently limited by high reverse leakage current, attributed to the discontinuity in the periodic crystal structure caused by mesa delineation. The Phase I efforts have successfully addressed this challenge by demonstrating a suitable thin solid film passivation on nBn Type-II SLS mesas. The Phase II effort will further this research by evaluating the newly developed passivation technology for pBp Type-II SLS devices, which are highly sensitive to surface inversion. To ensure optimal device performance, the passivation technology will be optimized to yield uniform, conformal, pinhole-free and stoichiometric composition, processed at low substrate temperatures.