DocumentCode :
1028863
Title :
A small-signal theory of avalanche noise in IMPATT diodes
Author :
Gummel, Hermann K. ; Blue, James L.
Author_Institution :
Bell Telephone Laboratories, Inc., Murray Hill, N. J.
Volume :
14
Issue :
9
fYear :
1967
fDate :
9/1/1967 12:00:00 AM
Firstpage :
569
Lastpage :
580
Abstract :
A general small-signal theory of the avalanche noise in IMPATT diodes is presented. The theory is applicable to structures of arbitrary doping profile and uses realistic ( \\alpha \\neq \\beta in Si) ionization coefficients. The theory accounts in a self-consistent manner for space-charge feedback effects in the avalanche and drift regions. Two single-diffused n-p diodes of identical doping profile, one of germanium and the other of silicon, are analyzed in detail. For description of the noise of the diodes as small-signal amplifiers the noise measure M is used. Values for M of 20 dB are obtained in germanium from effects in the depletion region only, i.e., when parasitic end region resistance is neglected. Inclusion of an assumed parasitic end resistance of one ohm for a diode of area 10-4cm2produces the following noise measure at an input power of 5×104W/cm2, and at optimum frequency: germanium 25 dB, silicon 31 dB. For comparison, a noise figure of 30 dB has been reported [1] for a germanium structure of the same doping profile as used in the calculations. Measurements of silicon diodes of the same doping profile are not available, but typically silicon diodes give 6-8 dB higher noise figures than germanium diodes of comparable doping profile.
Keywords :
Area measurement; Diodes; Doping profiles; Electrical resistance measurement; Feedback; Germanium; Ionization; Noise figure; Noise measurement; Silicon;
fLanguage :
English
Journal_Title :
Electron Devices, IEEE Transactions on
Publisher :
ieee
ISSN :
0018-9383
Type :
jour
DOI :
10.1109/T-ED.1967.16005
Filename :
1474728
Link To Document :
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