Title :
Microwave and millimeter wave QWITT diode oscillator
Author :
Kesan, V.P. ; Mortazawi, A. ; Neikirk, D.P. ; Itoh, T.
Author_Institution :
Dept. of Electr. & Comput. Eng., Texas Univ., Austin, TX, USA
Abstract :
The authors present the DC, microwave, and millimeter-wave characteristics of different quantum well injection transit time (QWITT) diodes. Small-signal and large-signal device models are used to provide physical device design parameters to maximize output power density. A peak output power of 1 mW in the frequency range of 5-8 GHz has been obtained from a planar QWITT oscillator. In addition, millimeter-wave oscillations at 28-31 GHz in a full-height waveguide circuit with an output power of 30 mu W have been obtained. Results on improving device efficiency by optimizing the design of the drift region through the use of a doping spike are also presented. By optimizing the doping concentration, and width of the doping spike, an increase in efficiency from 2% to 5% is obtained, without compromising on output power at X-band.<>
Keywords :
microwave oscillators; semiconductor device models; semiconductor diodes; semiconductor quantum wells; solid-state microwave devices; transit time devices; 1 mW; 2 to 5 percent; 28 to 31 GHz; 30 muW; 5 to 8 GHz; DC characteristics; QWITT diode oscillator; X-band; device efficiency; doping concentration; doping spike; frequency range; full-height waveguide circuit; large-signal device models; microwave characteristics; millimeter-wave characteristics; output power density; peak output power; physical device design parameters; planar QWITT oscillator; quantum well injection transit time; small signal model; Circuits; Diodes; Doping; Frequency; Local oscillators; Microwave devices; Microwave oscillators; Millimeter wave devices; Power generation; Voltage;
Conference_Titel :
Microwave Symposium Digest, 1989., IEEE MTT-S International
Conference_Location :
Long Beach, CA, USA
DOI :
10.1109/MWSYM.1989.38772
