摘要
We report a large-periphery lattice-matched In0.164Al0.836N/GaN depletion-mode (D-mode) metal-insulator-semiconductor high-electron-mobility transistor (MIS-HEMT) on a SiC substrate for high-current power switching. The stress-free InAlN barrier is lattice-matched to GaN, enabling scaling to a total gate width of 45 mm. The device delivers a continuous drain current of 24.7 A ( approximate to 550 mA/mm) at VDS=10 V with a threshold voltage of about -7.5 V, demonstrating strong high-current capability in D-mode operation. Dc and temperature-dependent measurements confirm robust current drive and a clear saturation knee up to 450 K, highlighting the benefits of the lattice-matched barrier and the high thermal conductivity of the SiC substrate. Small-signal measurements show that the input and output capacitances ( C-iss and C-oss ) remain in the range of several tens of picofarads with weak VDS dependence, while the reverse transfer capacitance C(rss )is about 1.46 pF ( approximate to 5 % of C-iss ) at 100 V, indicating limited Miller coupling between gate and drain. Consistent with these capacitance characteristics, 100-V double-pulse tests at a drain current of 1 A yield low turn-on and turn-off energies of approximately 4.2 mu J and 2.8 mu J, respectively, together with well-damped switching waveforms and no pronounced current collapse. Correlating the capacitance distribution with the measured switching metrics, this work demonstrates that lattice-matched InAlN/GaN D-mode MIS-HEMTs on SiC are promising building blocks for high-efficiency power conversion and cascode-based integrated voltage regulator architectures.