Thallium-Containing III-V Quaternary Compound Semiconductor for Use in Infrared Detection

117 Thallium-Containing III-V Quaternary Compound Semiconductor for Use in Infrared Detection--AstroPower, Inc., Solar Park, Newark, DE 19716-2000; (302) 366-0400 Mr. Zane A. Shellenbarger, Principal Investigator Mr. Thomas J. Stiner, Business Official DOE Grant No. DE-FG02-97ER82398 Amount: $75,000 Long-wavelength-infrared detection is widely used in several fields, including astronomy, environmental monitoring, infrared cameras, military sensors, law enforcement, medical sensors, and pollution monitoring. This project will investigate the incorporation of thallium (Tl) into III-V quaternary compound semiconductors for use in LWIR detector applications covering the wavelength range of 8 to 12 ¿m. Mercury cadmium telluride (HgCdTe) is currently most often used in this wavelength range. The proposed materials are expected to have several advantages over HgCdTe, including availability of lattice-matched substrates, better detector uniformity, better thermal stability, easier doping control, easier device processing, lower cost, and lower defect densities. The major goal of this project is to identify the optimum Tl-containing quaternary material and binary substrate combinations for LWIR detection. Liquid phase epitaxy will be used for the growth of these materials. During Phase I, the best candidate Tl-containing quaternary materials for LWIR detection will be identified using modeling and growth experiments. Fabrication and characterization of LWIR detectors in these best candidate materials will then be investigated. During Phase II, the best 1-2 Tl-containing quaternary materials for LWIR detection determined during Phase I will be further developed and optimized. Phase II will concentrate on improving the device performance and developing the manufacturing solutions required for the economic production of the large quantities of LWIR detectors and detector arrays. Commercial Applications and Other Benefits as described by the awardee: These new III-V detector materials will significantly improve the performance and cost of long wavelength infrared detectors and focal plane arrays. LWIR detection is widely used in several fields, including astronomy, environmental monitoring, infrared cameras, military sensors, law enforcement, medical sensors, and pollution monitoring.