Fig. 1. The schematic diagram of GaAs Schottky diode structure

Fig. 2. Surface channel planar diode (a) cross section (b) SEM image

Fig. 3. Air-bridge planar diode (a) cross section (b) SEM image

Fig. 4. Quasi-vertical diode fabricated by University of Virginia ^［10］

Fig. 5. Intrinsic small-signal equivalent circuit model of Schottky diode

Fig. 6. Simplified equivalent circuit model of Schottky diode under full-conducting biased conduction (a) and zero bias conduction (b)

Fig. 7. Cutoff frequency of Schottky diodes

Fig. 8. Cutoff frequency versus parasitic resistance and zero bias intrinsic capacitance

Fig. 9. The schematic diagram of the one-port S-parameters measurement method (a) and on-chip test structure (b)

Fig. 10. Equivalent circuit model of Schottky diode for one-port S-parameters measurement

Fig. 11. Extracted parasitic inductance and capacitance based on the one-port S-parameters measurement

Fig. 12. Comparison between modeled and measured S-parameters of one-port S-parameters measurement（Frequency range：1~110 GHz）

Fig. 13. The schematic diagram of the two-port series S-parameters measurement method (a) and on-chip test structure (b)

Fig. 14. Equivalent circuit model of Schottky diode for two-port S-parameters measurement

Fig. 15. Extracted parasitic inductance and capacitance values based on the two-port S-parameters measurement

Fig. 16. Comparison between modeled and measured S-parameters (Frequency range:1~75 GHz) (a) Current=10 mA (b) Current=0.1 mA