Enhancement-mode vertical (100) β-Ga₂O₃ FinFETs with an average breakdown strength of 2.7 MV cm⁻¹

Abstract

Abstract In this work, we report on the realization of vertical (100) β -Ga 2 O 3 FinFET devices for the use in power electronics applications. The experiments are carried out on structures consisting of highly conducting (100) β -Ga 2 O 3 substrates with a doping concentration N D of 3 × 10 18 cm −3 , and epitaxially grown layers with N D of 5 × 10 16 cm −3 for the drift and channel region. The fabricated FinFET devices feature enhancement-mode properties with a threshold voltage of +4.2 V and on/off-current ratio of 10 5 . Moreover, breakdown measurements of these devices reveal an average breakdown strength of 2.7 MV cm −1 . Additional device simulation indicates the presence of electric field peaks near the gate edge outside the active device as high as 7 and 5 MV cm −1 in the Al 2 O 3 gate oxide and β -Ga 2 O 3 semiconductor, respectively.