Teal’s Adaptation

By the end of World War II, scientists at the Bell Telephone Laboratories in Murray Hill, NY, had produced several metallurgical innovations that were to aid in the invention of the transistor. One of them, Gordon K. Teal, developed an effective method for growing germanium single crys­tals. The method he developed with J.B. Little, in the metallurgical laboratory of Bell Laboratories was essentially Czochralski’s method which was well known to metallurgists. Thus, Tea’s main contribution, besides convincing management that single crystals were important, was to extend the Czochralski method to the growth of non-metallic materials starting with germanium and soon thereafter silicon. Teal’s invention therefore

was essentially to transfer the Czochralski method from metallurgy to semiconductor physics and to provide the foundation for the industrial production of silicon.

While Teal and Little pulled their first single crystal of germanium on 1 October 1948, the first information about their method was provided by Bond et al. in 1950 in a short paper. They explained that “this method is described by G.K. Teal and J.B. Little in a paper to be presented by title before the Oak Ridge meeting of the Physical Society” held in March 1950. We can read in the 24-line abstract of their 10-min paper: “germanium single crystals (…) have been produced by means of a pulling technique distinguished from that of Czochralski and others in improvements necessary to produce controlled semi conducting properties”. The details of this method were never published in the version accessible to a wide audience. Thus, this statement indicates that the technique used by Teal and co-workers was essentially an improvement of the method invented by Czochralski 30 years before. Of course, this was an important improvement, but only an adaptation, as many others have done both before and afterwards. The same statement on the method was writ-ten in a short letter to the editor in Ref. In subsequent papers, however, Teal never mentioned Czochralski’s name again. This did not disturb the general scientific community, however, who adapted the name “Czochralski method” for this process and not something misleading like “Teal process”. And they were correct!

The text of a US patent from 13 July 1954(filed 12 January 1950) by Little and Teal, does not mention Czochralski directly but starts with the statement: “This invention is related to an improved method and apparatus for producing single crystals, particularly of germanium”. It is significant that the authors of this pat ent cited the paper by Hoyem and Tyndall who used the Czochralski – Gomperz method described by Linder!