Chien Cheng-Yen, Wu Wen-Hsin, You Yao-Hong, Lin Jun-Huei, Lee Chia-Yu, Hsu Wen-Ching, Kuan Chieh-Hsiung, Lin Ray-Ming
Graduate Institute of Electronic Engineering and Department of Electrical Engineering, National Taiwan University, Taipei, 10617, Taiwan, Republic of China.
Department of Electronic Engineering, Chang Gung University, Taoyuan, 333, Taiwan, Republic of China.
Nanoscale Res Lett. 2017 Dec;12(1):420. doi: 10.1186/s11671-017-2189-3. Epub 2017 Jun 17.
We present new normally off GaN high-electron-mobility transistors (HEMTs) that overcome the typical limitations in multi-mesa-channel (MMC) width through modulation of the via-hole-length to regulate the charge neutrality screen effect. We have prepared enhancement-mode (E-mode) GaN HEMTs having widths of up to 300 nm, based on an enhanced surface pinning effect. E-mode GaN HEMTs having MMC structures and widths as well as via-hole-lengths of 100 nm/2 μm and 300 nm/6 μm, respectively, exhibited positive threshold voltages (V ) of 0.79 and 0.46 V, respectively. The on-resistances of the MMC and via-hole-length structures were lower than those of typical tri-gate nanoribbon GaN HEMTs. In addition, the devices not only achieved the E-mode but also improved the power performance of the GaN HEMTs and effectively mitigated the device thermal effect. We controlled the via-hole-length sidewall surface pinning effect to obtain the E-mode GaN HEMTs. Our findings suggest that via-hole-length normally off GaN HEMTs have great potential for use in next-generation power electronics.
我们展示了新型常关氮化镓高电子迁移率晶体管（HEMT），通过调节通孔长度来克服多台面沟道（MMC）宽度的典型限制，以调控电荷中性屏蔽效应。基于增强的表面钉扎效应，我们制备了宽度高达300 nm的增强型（E模式）氮化镓HEMT。具有MMC结构、宽度分别为100 nm和300 nm且通孔长度分别为2 μm和6 μm的E模式氮化镓HEMT，其正向阈值电压（V）分别为0.79 V和0.46 V。MMC和通孔长度结构的导通电阻低于典型的三栅纳米带氮化镓HEMT。此外，这些器件不仅实现了E模式，还提高了氮化镓HEMT的功率性能，并有效减轻了器件热效应。我们通过控制通孔长度侧壁表面钉扎效应来获得E模式氮化镓HEMT。我们的研究结果表明，通孔长度常关氮化镓HEMT在下一代功率电子器件中具有巨大的应用潜力。
