PbSe Detectors for Low C-SWaP Focal Planes

TCII has teamed with Dr. Steve Jost and Dr. Zhisheng Shi to advance the performance of PbSe detectors for spectroscopic applications.   Jost joined TCII, but began his work in lead salt technology in 1978. While at BAE Systems, he led a team that developed a two-color PbSe sensor for missile threat warning based on a heterostructure photoconductor design and led BAE Systems’ effort on the DARPA WIRED program.   Professor Zhisheng Shi is a recognized leader in lead salt materials and devices and has established a state-of-the-art laboratory for the growth, fabrication, and testing of infrared detectors (from PVD and CBD PbSe to epitaxial PbSnSe and unique structures). His PbSe photoconductors are among the best reported at room temperature operation.  Dr. Furxhi and Dr. Driggers are experts in detector electronics, camera electronics, and infrared systems.   Dr. Furxhi was a Director of Imaging at IMEC.  Dr. Driggers was Director of the Modeling and Simulation Division at Army Night Vision Lab, Director of EO and Photonics Division at ARL, and Superintendent of Optical Sciences Division at NRL.  From WIRED, it was shown that about a factor of two decrease in the integrated noise density was achieved by the reduction of operating temperature from 300K to 240K.  Dark current restrictions require either long thin detectors or very thin PbSe unless a technique is found to lower the carrier density.  Hall calculations use the film’s thickness.  Others (Northrop, UVA,  Israel) showed it was surface conduction.   Prior data from SJOS (WIRED) showed 20-micron detector at 1V bias and 246K operating temperature yielded 2.5e-7A for a very PbSe layer of 2500 Angstroms.  In this proposal, we propose novel approaches to address those challenges. We will develop FPA using PbSe films with better homogeneity and leverage modern semiconductor processing technology to facilitate the manufacturing of cost-effective large format FPAs. We will also explore novel ways to alleviate the 1/f noise and high dark current.