Room Temperature Processed Ultrahigh-Frequency Indium-Gallium–Zinc-Oxide Schottky Diode

Despite being one of the most promising amorphous semiconductors, indium-gallium-zinc oxide (IGZO) has been mostly studied in transistors at low frequencies with limited effort on high-speed diodes. In this letter, the IGZO Schottky diodes with different active areas are fabricated in co-planar microwave waveguides on glass substrates at room temperature. By reducing the area of the diode, the cutoff frequency at zero bias can be improved. We are able to show that the diode with the active area of 200 μm
²
has an intrinsic cutoff frequency beyond 20 GHz. By connecting the diode with a load, the rectifying circuit also exhibits a cutoff frequency of 4.2 GHz with the input power of 15 dBm. Simulations based on the diode properties are performed to include intrinsic and extrinsic components, and the results agree well with the experimental data.