AlGaAs PIN diode multi-octave, mmW switches

The novel use of an AlGaAs/GaAs heterojunction to form a PIN diode, with reduced RF resistance (R
_S
) and no change in junction capacitance (C
_T
)[1]-[3], has been analyzed and employed in the development of several different PIN diode switches of various circuit topologies. Series designs demonstrate improved insertion loss, shunt designs improved isolation, and series-shunt designs improvements in both parameters. These switches demonstrate superior broadband performance, with low insertion loss and high isolation from 50MHz to almost 80GHz, and series-shunt switches exhibit 50% increased input power capability over equivalent homojunction GaAs PIN diode switches.