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This programme deals with 3 aspects of semiconductors, which are the subject of this week's course unit.
Metadata describing this Open University video programme
Module code and title: TS282, Electromagnetics and electronics
Item code: TS282; 05
First transmission date: 18-03-1973
Published: 1973
Rights Statement:
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Duration: 00:23:27
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Producer: Michael Weatherley
Contributors: William Shockley; John Sparkes; J. R. Haynes
Publisher: BBC Open University
Keyword(s): Chemical/physical structure; Diffusion; Drift; Germanium crystal; Germanium rod behaviour; Holes; Minority carriers; P-N junction; Recombination; Semiconductor
Footage description: John Sparkes introduces the programme. He lists those aspects of semiconductors which will be examined. Sparkes with a model of the crystal structure of pure germanium. He tilts it various ways to show its symmetry. Film sequence shows germanium purification process. Germanium oxide is the raw material. A series of controlled furnaces reduce it to its metallic state. The "Zone Refining Technique", used to remove impurities, is shown and explained. Film shots of silicon crystals being purified. Film shots of semiconductor materials being manufactured into semiconductor devices. Materials are sliced and ground. Sparkes introduces a film sequence showing the Shockley-Haynes experiment which demonstrated the existence of electron/hole pairs in semi conductor materials. Film, sequence shows Shockley and Haynes re-doing their 1949 experiment which demonstrated the existence of electron/hole pairs with the properties of diffusion, drift and re-combination in semiconductors. Note: condensed version also in TS251/08. Sparkes sums up the Shockley-Haynes experiment. Sparkes examines the principle of the p-n junction diode. He starts with a diagram of silicon crystal structure in two dimensions with square symmetry. The diagram shows p type crystal made with the introduction of boron. n type crystal made with the introduction of phosphorous Diagram of a p - n Junction showing the diffusion of carriers process. Sparkes explains how p - n Junction operates. Graph of density against distance through junction aids.
Master spool number: 6LT/70264
Production number: 00521_2101
Videofinder number: 699
Available to public: no