Research On The Switch Device And Switch Circuit Of GaAs MOSFET

With the development of communication techniques, higher performance of on/offspeed, power handling and insertion loss is required for radio-frequency (RF) switchesin the application of mobile communications, radar and satellite communications.Among common RF switch devices, solid field effect transistor (FET) stands out for itsexcellent performance and high integrated level, while Si based silicon-on-insulator(SOI) devices and GaAs based high mobility electronic transistor (HEMT) devices aremost widely used in solid FETs. Centering in GaAs MOSFET, researches shown beloware conducted in this thesis.1. Basis of GaAs devices was introduced. Comparison of GaAs MOSFET andGaAs HEMT was done in this paper. Research was also done in the condition for postdeposition annealing (PDA) in oxygen ambient for GaAs MOS structure, and arelatively optimum thickness of dielectric layer was given together with the discussionof the factors affecting GaAs MOS annealing property.2. Fundamentals of RF switches were introduced. An InGaP/InGaAs MOSFETapplying on RF switches was fabricated based on the InGaP/InGaAs MOSFETsfabrication process with its gate length of0.5μm. DC and S parameter measurement wasdone to show its RF switch characters. According to the result of measurements, a SP4Tswitch was designed.