Title :
An electrically and optically gate-controlled Schottky/2DEG varactor
Author :
Anwar, Amro ; Nabet, Bahram ; Culp, James
Author_Institution :
Dept. of Comput. Eng., Drexel Univ., Philadelphia, PA, USA
Abstract :
A novel gate-controlled varactor is reported. The three-terminal varactor is a modulation-doped heterostructure of AlGaAs/GaAs with two Schottky contacts directly made to a two-dimensional electron gas (2DEG). The third, gate, contact is formed from highly doped n/sup +/ GaAs material to allow an open optical window that can be used for optical gating and mixing. Structure capacitance is less than 1 pF and a change of more than 30% from the zero bias capacitance is observed with the applied gate voltage. The capacitance also increases proportionally with applied light and inversely with the terminal voltage.
Keywords :
Schottky barriers; harmonic oscillators (circuits); metal-semiconductor-metal structures; two-dimensional electron gas; varactors; voltage-controlled oscillators; AlGaAs-GaAs; Schottky contacts; applied gate voltage; applied light; capacitance; gate-controlled varactor; modulation-doped heterostructure; open optical window; optical gating; terminal voltage; three-terminal varactor; two-dimensional electron gas; Capacitance; Contacts; Electron optics; Epitaxial layers; Gallium arsenide; Optical mixing; Optical modulation; Schottky barriers; Varactors; Voltage;
Journal_Title :
Electron Device Letters, IEEE
