A new 18-element small-signal model for GaN high electron mobility transistor is presented to operate at very high frequencies around 70 GHz. This model accounts for the need of a capacitor to represent the capacitive effect between the end of the drain electrode and contacting pad of the gate electrode. An extrinsic parasitic gate-drain capacitance as for higher frequencies this parameter becomes significant even under cold-FET conditions. This novel approach compensates for the high linear dependency of inductance at such high frequencies and the improved performance is evident in the S-parameter modelled. The validity of the proposed model has been well-illustrated up to 100 GHz frequency by the modelled S-parameters.
B. S. Mahalakshmi, Manikantan, S., Bhavana, P., Prem, A. M., SaiEknaath, R. S. S., and Dr. Nirmala Devi M., “Small signal modelling of GaN HEMT at 70GHz”, International Conference on Signal Processing and Integrated Networks (SPIN), 2014 . IEEE, Noida, Delhi-NCR, India, pp. 739 - 743, 2014.