Resistance of GaAS Varactor Diodes for TV Tuners

Gallium arsenide varactor diodes have been extensively used in microwave applications because of high Q. But few papers have reported the diodes for UHF use, 1,2) although strongly requested to realize low noise TV tuners satisfying with the FCC noise figure requirement. In order to cover wide tuning frequency range as is used in TV UHF broadcasting band with varactor diodes, hyperabrupt diodes are needed. Hyper-abrupt GaAs diodes have been manufactured by a double epitaxial growth technique.1,2) These diodes for microwave use are commercially available.