HyFET—A GaN/SiC Hybrid Field-Effect Transistor
Sirui Feng, Zheyang Zheng, Yuru Wang, Gang Lyu, Kai Liu, Yan Cheng, Junting Chen, Tao Chen, Li Zhang, Wenjie Song, Hang Liao, Yat Hon Ng, Mengyuan Hua, Kai Cheng, Jin Wei, Kevin J. Chen
Abstract
We experimentally demonstrate a GaN/SiC hybrid field-effect transistor (HyFET)—a novel power electron device that can harness the complementary merits of GaN and SiC and circumvent their notorious drawbacks. The HyFET regulates currents by gating an AlGaN/GaN high-mobility 2- dimensional-electron-gas (2DEG) channel and blocks voltages with a vertical SiC junction-field-effect-transistor (JFET) structure. The channel mobility can be boosted by ~100 times compared to a SiC MOS-channel. The HyFET can be vertically configured to provide voltage blocking with avalanche capability and be free of the dynamic ON-resistance issue, which are difficult for GaN HEMTs. Critical technology enablers for implementing the GaN/SiC HyFET include a dual-epitaxy SiC JFET structure, GaN epitaxy on patterned 4°- off-axis 4H-SiC substrate, and a Damascene-process-based in- cell interconnection solution. Our experimental demonstration unveils a new power device platform that gears toward the utmost integration of these two prevailing wide-bandgap semiconductors.