Creator:H. Tracy Hall,John Dismukes
Date Created:June 29, 1964,July 2. 1964
Place Created:
Keywords:H. Tracy Hall,John Dismukes,June 29, 1964,July 2. 1964
Context:
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July 2. 1964
Dr. John Dismukes
Radio Corporation of America
RCA Laboratories
Da/id Sarnoff Research Center
Princeton. Kew Jersey
Dear Dr. Dismukes

Thanhs vary much for your letter of June 29, the papers describing your work on germanium -silicon alloys, and for the germanium-silicon alloy samples. We certainly appreciate your generosity in supplying this material to
I have a post-doctoral fellow coming to work with me about August 15. and 1 hope to start him on a program wherein we will take x-ray diffraction patterns of these materials at pressures a little beyond 100 kb.
V, e would like to take powder photographs of pure silicon and pure germanium powders at these high pressures, in addition to taking patterns on the alloys. Would it be possible for you to
supply powders of the pure materials?
Vv ith regard to the specimen bars, I would think an impurity concentration about 2 x 10.™ cm-3 with phosphorus being the impurity would be all right. Alloys in the range of 15 50 atomic % jerr.,,anium and 30 atomic % germanium would be satisfactory If you do not have these on hand, we would certainly consider other dopings and alloy compositions.	7
Very truly yours,
H. Tracy Hall Director of Research
Room 224 J21B
June 29, 1964
Prof. H. Tracy Hall Director of Research Room 224 ELB, Research Div. Brigham Young University Provo, Utah 84610
Dear Prof. Hall:
In view of the experimental difficulty in preparing homogeneous samples of Ge-Si alloys we are happy that someone else can also make use of them. In a separate package you will receive fifteen samples of Ge-Si alloy. The lattice parameter, density, and composition in Atomic "L Germanium are listed in Table III of the manuscript, "Lattice Parameter and Density in the Ge-Si Alloy System", which is included with this letter. These samples are thus the very same which were used in our study. Since they were already powdered and their properties were well defined, we are sending them in spite of the fact that their weights are only about 1/2 gm each. If they are unsuitable, we can cut further slices of material.
Enclosed also is a manuscript, "Thermal and Electrical Properties of Heavily Doped Ge-Si Alloys up to 1300°K". It will give you some idea of the work done on doped Ge-Si alloys. We can supply the specimen bars you mentioned, but not at all compositions and all carrier concentrations. Samples are available principally at 80 at % Ge and at 15-50 at 7« Ge. Therefore, we would like to know what resistivity or carrier concentration range you wish, what doping agent, and approximately what compositions?
Dr. Ekstrom and I have been working jointly on this program, so that any acknowledgment for the samples should go to us both. Please feel free to request further material. The samples #1-15 we are sending immediately because they are ready to go.
Very truly yours.
John Dismukes