Hot-Electron Effects in AlGaN/GaN HEMTs Under Semi-on DC Stress

An analysis of hot-electron (HE) effects on the dynamic resistance ( ${dR}\,_{\mathrm{\scriptstyle ON}}$ ) of AlGaN/GaN high-electron-mobility transistors (HEMTs) when subject to semi-ON stress is reported and compared with OFF-state stress. This is carried out using measurements and TCAD 2-D hydrodynamic simulations. Two structures with different distances between the highly carbon-doped buffer region and the two-dimensional electron gas (2DEG) are here considered. The additional ${dR}\,_{\mathrm{\scriptstyle ON}}$ in semi-ON is attributed to HEs trapping at the passivation/AlGaN interface. TCAD simulations are performed and compared with experimental results.