3D modelling and experimental results of Multichannel Monolithic-Cascode HEMT (MC2-HEMT)

This study concentrates on modeling of the SJ multichannel AlGaN/GaN transistor, with the analysis of carrier dynamics applicable to a generic charge-balanced, multichannel HEMT built upon a common technology platform. The 3D TCAD model developed in this study is calibrated against the experimental data of a recently demonstrated Multichannel Monolithic-Cascode HEMT (MC²-HEMT), which upscales GaN HEMT to 10 kV with specific Ron lower than the 1D SiC limit. In this work, the multichannel main block is extracted as a model in simulation. We then deploy this model to compare the carrier dynamics in (i) an ideal, un-doped SJ multichannel and (ii) a doped, RESURF multichannel. In the second case (ii), the balance between the 2DHG and the 2DEG has been disrupted. Simulation analysis shows that for UID multichannel devices, the top p-GaN cap plays a crucial role in balancing the overall carrier equilibrium of the device and aids in channel depletion. This work innovatively designs and uses a TCAD model to analyze characteristics of multichannel devices, providing a theoretical foundation for fabrication and experimentation and contribute to the design of SJ multichannel power devices in the future.