Enhancement-mode Ga2O3 wrap-gate fin field-effect transistors on native (100) β-Ga2O3 substrate with high breakdown voltage

Sn-doped gallium oxide (Ga2O3) wrap-gate fin-array field-effect transistors (finFETs) were formed by top-down BCl3plasma etching on a native semi-insulating Mg-doped (100) β-Ga2O3 substrate. The fin channels have a triangular cross-section and are approximately 300  nm wide and 200 nm tall. FinFETs, with 20 nm Al2O3 gate dielectric and ∼2 μm wrap-gate, demonstrate normally-off operation with a threshold voltage between 0 and +1  V during high-voltage operation. TheION/IOFF ratio is greater than 105 and is mainly limited by high on-resistance that can be significantly improved. AtVG = 0, a finFET with 21 μm gate-drain spacing achieved a three-terminal breakdown voltage exceeding 600  V without a field-plate.

Source: Applied Physics Letters - November 21, 2016 Category: Physics Authors: Kelson D. Chabak, Neil Moser, Andrew J. Green, Dennis E. Walker Jr., Stephen E. Tetlak, Eric Heller, Antonio Crespo, Robert Fitch, Jonathan P. McCandless, Kevin Leedy, Michele Baldini, Gunter Wagner, Zbigniew Galazka, Xiuling Li and Gregg Jessen Source Type: research