First demonstration of heterojunction-free GaN nanochannel FinFETs

Heavily doped GaN nanochannel FinFET has been proposed and fabricated, for the first time, which does not have any p-n junction or heterojunction. In spite of its easy and simple epitaxial growth and fabrication process, the fabricated device with nanochannel width of 80 nm and gate length of 1 μm exhibited excellent off-state performances such as extremely low off-state leakage current of ∼ 10⁻¹¹ mA with BV of ∼ 300 V and subthreshold slope of 68 mV/decade, very close to the theoretically limited value, which leads to high Ion/Ioff ratio of 10⁷ ∼ 10⁹. The device also exhibited high on-state performances such as maximum drain current of 562 mA/mm and maximum transconductance of 138 mS/mm. The proposed nanochannel GaN FinFET can be very promising candidate not only for high performance, but also high power applications.