Long Wavelength Infrared Superlattice Detectors and FPAs Based on CBIRD Design

Abstract

In this letter, we demonstrate the next generation of N+-p complementary barrier infrared detectors (nCBIRD) with 9.9 μm cutoff wavelength that have near zero bias operation and exhibit dark current density of 6 × 10 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">-6</sup> A/cm <sup xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">2</sup> at 77 K. These nCBIRDs have been recently utilized in the 320 × 256 focal plane array that exhibited a noise equivalent differential temperature of 18.6 mK at an operating temperature of 77 K, with a 300 K background and <i xmlns:mml="http://www.w3.org/1998/Math/MathML" xmlns:xlink="http://www.w3.org/1999/xlink">f</i> /2 cold-stop. We compare single pixel photodiode characteristics with the performance of FPAs that were fabricated together on the same wafer. This letter identifies the physical processes affecting the performance of long wave infrared photodetectors based on CBIRD design.