PNP structures have been investigated and the various effects encountered described in terms of fundamental aspects of carrier flow. The capacitance of a reverse biased junction in a pnp structure is found to rise abruptly with increase of its reverse bias past the punch-through voltage. This effect arises from the addition of the capacitance of the second junction by the low resistance connection of the space charge column across the n region. An unusual phenomenon called "induced breakdown" is found to occur in certain grown junction transistors. Here the punch-through effect of the space-charge spreading from one junction causes the other junction to suffer avalanche breakdown. Negative resistance is observed in some pnp diodes. This is shown to be a result of the current dependence of the hole transmission process occuring in the n-type transmission region combined with the multiplication effect in the high field region at the collector junction. Current flow in the thin base diode is of a space-charge limited nature in the n region. It is shown that the field over most of the n region is large enough to cause the hole mobility to decrease many fold from its low field value. The slope resistance of a typical diode tends asymptotically to a constant value which is approximately consistent with the model based on a saturated drift velocity for holes in the n region. / Science, Faculty of / Physics and Astronomy, Department of / Graduate
Identifer | oai:union.ndltd.org:UBC/oai:circle.library.ubc.ca:2429/40862 |
Date | January 1957 |
Creators | Barker, Alfred Stanley, Jr. |
Publisher | University of British Columbia |
Source Sets | University of British Columbia |
Language | English |
Detected Language | English |
Type | Text, Thesis/Dissertation |
Rights | For non-commercial purposes only, such as research, private study and education. Additional conditions apply, see Terms of Use https://open.library.ubc.ca/terms_of_use. |
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