An ${({\rm Al}_{\rm x}{\rm Ga}_{1-{\rm x}})}_{2}{\rm O}_{3}$ Metal-Semiconductor-Metal VUV Photodetector

The authors report the conversion of AlGaN epitaxial layer into (Al
_x
Ga
_1-x
)
₂
O
₃
thin film by furnace oxidation at high temperature in oxygen containing ambient. A vacuum-ultraviolet (Al
_x
Ga
_1-x
)
₂
O
₃
photodetector (PD) was also fabricated. It was found that external quantum efficiency of the fabricated PD measured at 220 nm was 30%. It was found that the fabricated PD exhibits extremely large deep-UV-to-visible rejection ratio.