Single-photon negative feedback APD focal plane array with 2.2 um cutoff wavelength

Princeton Lightwave proposes to develop a solid state short-wavelength infrared (SWIR) detector technology with true single photon sensitivity and a cutoff wavelength beyond 2.2 um. Both single photon avalanche diodes (SPADs) and negative feedback avalanche diodes (NFADs) will be fabricated. These detectors can be readily integrated into large-format focal plane arrays (FPAs), and array format of 32 x 32, 128 x 32 and 128 x 128 will be fabricated. Both active and passive imaging capability of these array devices will be demonstrated. Extended wavelength response to 2.2 um and beyond will be achieved using a novel type II superlattice absorbers grown on InP substrates. Planar-geometry diffused-junction device structure will be adopted for fabricating these devices, which will lead to low dark count rate and long term device stability. To carry out the proposed development work, we will leverage our past success in manufacturing industry best-in-class InP based SPADs and NFADs and the realization of high-performance arrays of Geiger-mode avalanche diodes as large as 128 x 32. The detector technology to be developed will provide a unique solution to many applications that require single photon level sensitivity across the full SWIR spectral band.