The RIS device - A resistor-insulator-semiconductor microwave switch

This paper describes the design, fabrication and characteristics of a new device capable of switching large microwave power at extremely low drive power levels. The new device is a novel resistor-insulator-semiconductor (RIS) structure which switches a microwave signal between two terminals by the application of a D.C. bias on a third, or control, terminal. The device embodies several unique features including the use of resistive titanium dioxide as a gate electrode and the use of an insulating TiO2/ SiO2composite dielectric as the gate insulator. The device has exhibited a diode OFF/ON ratio in excess of 1500, an insertion loss of 1.2 dB and has switched 100 watts of Rf power at a control level of less than 1µwatt in a 3.5 GHz 4-bit phase shifter.