@article{Labed2026, 
author = {Madani Labed and Ho Jung Jeon and Jang Hyeok Park and Kwangsik Jeong and You Seung Rim},
title = {P-type LiyNi1-x-yMgxO: A promising ultrawide bandgap semiconductor for Ga2O3 power devices applications},
year = {2026},
journal = {Journal of Magnesium and Alloys},
volume = {15},
number = {C},
keywords = {Power electronics, β-Ga2O3, LiyNi1-x-yMgxO, Threshold voltage, Breakdown voltage},
url = {https://www.sciopen.com/article/10.1016/j.jma.2025.10.005},
doi = {10.1016/j.jma.2025.10.005},
abstract = {Ultrawide bandgap (UWBG) semiconductors are essential for the next generation of power electronics, offering superior breakdown voltages, thermal stability, and energy efficiency compared to conventional materials. However, the absence of efficient p-type UWBG semiconductors has been a major challenge, limiting the development of complementary devices. In this study, we explored LiyNi1-x-yMgxO as a potential p-type UWBG semiconductor, employing co-sputtering techniques to precisely control the Mg content by adjusting the power density applied to Mg target. X-ray diffraction (XRD) revealed enhanced (200) and (111) diffraction peaks with increasing Mg content, confirming successful incorporation of Mg into the NiO lattice. X-ray photoelectron spectroscopy (XPS) further validated the substitution of Ni by Mg atoms. As the Mg target power density increased from 0 to 1 W·cm-2, the optical bandgap widened from 4.27 eV to 5.44 eV, with corresponding improvements in optical transmittance. Hall effect measurements indicated a decrease in hole concentration with a significant enhancement in hole mobility as Mg content increased and reached 33.39 cm2V-1s-1 for 17.80 % Mg fraction. Despite the higher Mg fraction increasing the band alignment with n-type β-Ga2O3, a reduction in turn-on voltage with increasing Mg fraction compared with Li-doped NiO/β-Ga2O3 heterojunction diode (HJD) and an impressive BV of -1450 V were observed for films containing 17.80 % Mg. Silvaco TCAD simulations attributed these variations to trap-assisted tunneling, likely facilitated by Mg-induced energy levels within the Li-doped NiO matrix, which contributed to the reduction in turn-on voltage. The favorable electrical and optical properties of LiyNi1-x-yMgxO films, along with the successful integration of LiyNi1-x-yMgxO with β-Ga2O3 for heterojunction devices, demonstrate that LiyNi1-x-yMgxO is a promising candidate for future p-type materials in UWBG power device applications, particularly in conjunction with n-type β-Ga2O3 and other UWBG semiconductors.}
}