Institution: | McGill University |
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Department: | Department of Engineering. |
Degree: | Master of Engineering. |
Year: | 1956 |
Keywords: | Electrical Engineering. |
Record ID: | 1557724 |
Full text PDF: | http://digitool.library.mcgill.ca/thesisfile110202.pdf |
A photoconductive diode can be constructed from a bar of semi-conducting material containing a region of p type conductivity and one of n type conductivity. However, a more sensitive device is realized if three regions are used alternately n,p,n. The npn structure, a phototransistor, provides a current approximately fifty times greater than that obtained from a pn photodiode illuminated by the same light source. Several of these npn units were constructed and the performance of each as a two-terminal phototransistor was evaluated.