Abstract
This paper presents our recent studies on GaN-on-Si devices and technologies for RF and microwave applications. The considerations of layer structure and fabrication technology are reviewed including two different GaN-based heterostructures and optimization of ohmic and Schottky contacts. Also, the proposed novel approaches for achieving high speed GaN-on-Si HEMTs are addressed such as the hybrid-drain structure and silicon substrate removal technology. Finally, the small-signal equivalent circuit model is employed to analyze the parasitic effects of silicon substrate for the device at high frequencies.