Title :
Design and analysis of a traveling-wave MESFET with enhanced shielding capabilities
Author :
Yarbrough, A.D. ; Osofsky, S.S.
Author_Institution :
Electron. & Sensors Div., Aerosp. Corp., Los Angeles, CA, USA
fDate :
9/1/1994 12:00:00 AM
Abstract :
The Concentric MESFET (CMESFET) is a small-signal, traveling-wave transistor in which a grounded source electrode surrounds and shields the gate and drain electrodes from electromagnetic fields generated by other nearby circuit elements. S-parameters for the transistor are computed to obtain gain curves for several design configurations. For a gate length of 2 μm, maximum gain occurs with a gate width of 3.0 mm. The CMESFET has a calculated bandwidth of 17 GHz for this gate length and a gate width of 300 μm. Coupling capacitances between device electrodes and a nearby transmission line are calculated to demonstrate how the shielding source electrode isolates the device from interference and crosstalk originating in the surrounding circuit. The CMESFET geometry exhibits shielding characteristics better than those of conventional small-signal FET geometries
Keywords :
S-parameters; Schottky gate field effect transistors; crosstalk; electromagnetic interference; shielding; solid-state microwave devices; 17 GHz; 2 micron; 3.0 mm; 300 micron; CMESFET; Concentric MESFET; S-parameters; coupling capacitances; crosstalk; design; electromagnetic fields; gain curves; grounded source electrode; interference; shielding; small-signal FET; transmission line; traveling-wave transistor; Bandwidth; Capacitance; Coupling circuits; Distributed parameter circuits; Electrodes; Electromagnetic fields; Geometry; Interference; MESFET circuits; Scattering parameters;
Journal_Title :
Microwave Theory and Techniques, IEEE Transactions on
