Page 239 - Chalcogenide Glasses for Infrared Optics
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AMI Infrar ed Crystalline Materials    215


                                                      CdTe strips

                               3"








                        2"                                  Graphite





                                    Graphite strip for end piece
              Saw planes



















              FIGURE 9.3  Formation of large area mosaic CdTe substrates.


        9.3  AMI DARPA-Funded Large Plate Process
              Some 10 years later, in 1981, the author met with his ex-TI colleague
              Dick Reynolds for lunch in Washington, D.C. Dick Reynolds had
              become the deputy director for DARPA and was heavily involved in
              building support for the production of many thousands of HgCdTe
              detector arrays that would be needed in the very near future. Con-
              ventional methods of producing CdTe for substrates were much too
              slow. What was needed was a new approach to produce large plates
              of CdTe. Together they decided that the AMI process for producing
              large plates of high-purity chalcogenide glasses could be modified to
              produce CdTe plates with increased size and purity. A plan was made
              and a proposal written for an effort to produce plates of 6-, 8-, and
              10-in diameter. The first contract was DARPA-funded MDA903-82-
              C-0159 followed by DARPA Contract No. DAAG-29-85-C0004 funded
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