EPITAXIAL IR MATERIALS TECHNOLOGY FOR HIGH PERFORMANCE 2ND GENERATION SYSTEMS

IN THE LAST SEVERAL YEARS, UNDER EXTENSIVE GOVERNMENT AND INDUSTRY R&D EFFORTS, GREAT ACHIEVEMENTS HAVE BEEN ACCOMPLISHED IN THE DEVELOPMENT OF HGCDTE INFRARED TECHNOLOGY. LWIR INFRARED FOCAL PLANE ARRAYS HAVE BEEN MADE AND HGCDTE EPILAYERS CAN BE PRODUCED BY NOT ONLY LPE BUT ALSO VARIOUS VAPOR PHASE METHODS. HOWEVER, AMONG ALL OF THESE SUCCESSES, THERE IS A BIG PROBLEM TO BE SOLVED, I.E. THE LOW DETECTOR ARRAY YIELD. BASED ON OUR ANALYSIS, THERE ARE THREE TYPES OF POOR PV DEVICES, AND CRYSTALLINE DEFECTS ARE MOST LIKELY RESPONSIBLE FOR THE POOR DEVICE PERFORMANCE. THE GOAL OF THIS PROGRAM IS THEREFORE TO DISCOVER THESE DEFECTS AND TO DEVELOP METHODS TO AVOID OR TO ELIMINATE THEM. IN THE PHASE I PROGRAM, WE WILL STUDY THE CAUSE OF TE PRECIPITATES AND THEIR EFFECTS TO THE MATERIALS AND DETECTORS BOTH THEORETICALLY AND EXPERIMENTALLY. IN ADDITION, CRYSTALLINE DEFECTS IN ZNCDTE SUBSTRATES WILL BE IDENTIFIED AND THEIR EFFECTS ON THE LPE LAYERS WILL BE CHARACTERIZED.