부산대학교 도서관

A p-type IrOx was first applied to $\beta $ -Ga2O3 p-n heterojunction diodes (HJDs) in this work. It was fabricated by oxygen ion beam-assisted deposition (IBAD) method with a hole concentration of $10^{{21}}$ /cm3. Ir $^{{3}+}$ is the main valence state confirmed by X-ray photoelectron spectroscopy (XPS). The bandgap of 2.9 eV was determined by the transmittance spectrum, which is consistent with the HSE06 calculated band structure of Ir2O3. p-n HJDs were realized by deposition p-type IrOx layer on a lightly doped n-type $\beta $ -Ga2O3 epitaxial layer without optimized electric field management techniques. A high breakdown voltage ( ${V} _{B}$ ) of 1005 V and a relatively low specific ON-resistance ( ${R} _{{ \text {ON, sp}}}$ ) of 4 $\text{m}\Omega \cdot $ cm2 were achieved. In particular, the reverse leakage current density remained below $0.1 ~\mu \text{A}$ /cm2 before breakdown. The results provide a new way to develop high-quality $\beta $ -Ga2O3 p-n heterojunction.