Investigation of the nanochannel geometry modulation on self-heating in AlGaN/GaN Fin-HEMTs on Si

摘要

The impact of the nanochannel geometry on the thermal performance of AlGaN/GaN Fin-HEMTs was investigated. Structures with a larger nanochannel space (S-fin) or a smaller nanochannel width (W-fin) show the suppressed self-heating effect, which was confirmed by the smaller dispersion between DC and pulsed measurements together with the reduced high temperature degradation of the drain current. A closed-form expression based on the heat flow theory was used to illustrate the coupling effect of W-fin and S-fin, and the channel temperature was mapped considering the different nanochannel geometries. As W-fin and S-fin scale down simultaneously, the nanochannel structure would present a much lower channel temperature, demonstrating that the heat generation dominated by W-fin has a greater impact on the self-heating in Fin-HEMTs.