“…Beta-gallium oxide (β-Ga 2 O 3 ), an ultrawide bandgap semiconductor ( E g > 4.9 eV), has garnered significant attention due to its large Baliga’s figure of merit and high breakdown electric field of ∼8 MV cm –1 . − This makes β-Ga 2 O 3 as a promising candidate for high power, high frequency and high-temperature electronics applications in harsh environment . Additionally, it has proven suitable for optoelectronics applications such as solar blind deep-UV photodetectors and solar cells. − Nevertheless, the development of β-Ga 2 O 3 Schottky barrier diodes has been hindered by a low Schottky barrier height with metals. , An efficient solution involves constructing bipolar all-oxide pn heterojunction devices with β-Ga 2 O 3 and various p-type oxides . In recent years, β-Ga 2 O 3 has been integrated into various pn heterojunctions, including those with Cu 2 O, , SnO, , CuAlO 2 , and NiO. ,, Among them, Cu 2 O shows excellent electrical properties due to its remarkable hole mobility (up to 263 cm 2 V –1 s –1 ) and shallow acceptor levels .…”