William Gardner Pfann

William " Bill" Gardner Pfann ( born October 27, 1917 in Brooklyn, New York, † 22 October 1982) was an American materials scientist at Bell Laboratories, known for the development of the zone melting method, the important for producing high purity, single-crystal semiconductor is.

Pfann was in 1935 in the chemistry department of Bell Laboratories. By the way, he studied at night school at the Cooper Union College with a bachelor's degree in chemical engineering 1940. He remained at Bell Laboratories until his retirement in 1982. Few weeks later he died.

After the war he worked with the group of William B. Shockley, Walter Houser Brattain, including, at Bell Labs in the development of diodes and transistors from the first peak semiconductors ( first germanium). He made important contributions to the first production transistor ( called type A).

Pfann developed 1950/51 the zone melting method, first for germanium. Here, a germanium rod was repeatedly pushed by a horizontally spaced series of induction coils, the impurities to the melt zone wandered through the bar. This impurity levels could be achieved by only up to a hundredth ppm and later 1 ppb ( an improvement by a factor of 1000 compared to before). Silicon, which had a higher melting point could be treated with a developed at Bell Labs in 1952 by Henry Theurer variant of the method (float zone refining ). At the same time this happened by Paul H. Keck and Marcel JE Golay at the U.S. Army Signal Corps at Fort Monmouth and R. Emeis in the laboratory of Eberhard Spenke at Siemens in Pretzfeld.

Pfann held 65 patents, mostly in the area of ​​zone melting. He was a member of the National Academy of Sciences (1975 ), was a Fellow of the Metallurgical Society and the American Society of Metals. In 1976 he was awarded with the James C. Theurer McGroddy Prize for New Materials of the American Physical Society. In 1968 he was awarded the Creative Invention Award of the American Chemical Society.

Writings

  • Zone melting, Wiley 1958, 3rd edition, Krieger Publishing 1978
  • Principles of Zone Melting, Transactions of the American Institute of Mining and Metallurgical Engineers, Vol 194, 1952, pp. 747-753
  • Zone Melting, Science, Volume 135, 1962, pp. 1101-1109
October 22 Materials science William Shockley Marcel J. E. Golay Physics Today
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