Accession Number : AD0844679

Title :   Advanced Concepts of Microwave Generation and Control in Solids.

Descriptive Note : Quarterly progress rept. no. 3, 1 Apr-30 Jun 68,

Corporate Author : CORNELL UNIV ITHACA NY SCHOOL OF ELECTRICAL ENGINEERING

Personal Author(s) : Dalman, G. C. ; Eastman, L. F.

Report Date : OCT 1968

Pagination or Media Count : 124

Abstract : Research was conducted on Gunn oscillators. Successful hybrid mode operation has been obtained over 0.75 to 5 times transit-time frequency in single diodes of epitaxial GaAs. Research was conducted on avalanche (IMPATT) diodes. The broadband negative resistance properties of a 1.3 ohm-cm, 4.5 micron N-region punch-through avalanche diode have enabled its operation as a microwave generator over a 1 to 10 GHz frequency range with 2 to 10 percent efficiency. Large-signal sample impedances were obtained for both the pure transit-time mode and the low-frequency mode was found to be characterized by the necessary presence of an idler frequency at the second harmonic. Research on gallium arsenide crystal growing is also reported. Work on the solution growth method has shown considerable promise. An elementary theory for the magnetoresistance measurement of the Hall mobility, including the correction for the finite geometry of the practical diodes, is presented, and several practical sources of measurement error are discussed. (Author)

Descriptors :   *GALLIUM ARSENIDES), (*MICROWAVE OSCILLATORS, (*SEMICONDUCTOR DIODES, MICROWAVE OSCILLATORS), CRYSTAL GROWTH, EFFICIENCY, POWER, NEGATIVE RESISTANCE CIRCUITS, CAVITY RESONATORS, X BAND, HALL EFFECT, SIMULATION, SPACE CHARGE, SOLUTIONS(MIXTURES).

Subject Categories : Electrical and Electronic Equipment
      Solid State Physics

Distribution Statement : APPROVED FOR PUBLIC RELEASE