A Novel GaN Superjunction FinFET Power Device With a P-Type NiO Pillar for Improved Performance

Fin field-effect transistor (FinFET) concept has been used to develop a new generation of vertical power devices based on gallium nitride (GaN) material. For the conventional GaN FinFET, the specific ON-resistance (
${R} _{\text {on},\text {sp}}$
) is still high, which imposes limitations on device design. In this article, a novel p-type nickel oxide (p-NiO) pillar GaN superjunction (SJ) FinFET is proposed. The proposed GaN SJ FinFET eliminates the issues of high ionization energy and low activation rate of impurities in p-type doping, realizes a new SJ charge compensation drift region, which greatly increases the breakdown voltage (BV) and reduces the
${R} _{\text {on},\text {sp}}$
of the device. In order to get highest figure of merit (FOM = BV2/
${R} _{\text {on},\text {sp}}$
), the parameters of the proposed device are optimized. Finally, the
${R} _{\text {on},\text {sp}}$
of the proposed GaN SJ FinFET and the conventional GaN FinFET are 0.274 and 0.969
$\text{m}\Omega \cdot $
cm2 respectively, which is reduced by more than 71%. And the threshold voltage is pushed forward to 2.25 V compared with 0.5 V of the conventional structure. The effect of incomplete ionization of NiO on the BV of the proposed device is also investigated. The proposed GaN SJ FinFET provides a new approach for realizing SJ devices on GaN material and has promising application prospects.