“…5 Many ultrawide bandgap semiconductors, including high-aluminum-content gallium nitride (AlGaN, 4.4-5.1 eV), [6][7][8] aluminum nitride (AlN, 6.2 eV), 1,9 gallium oxide (Ga 2 O 3 , 4.4-5.3 eV), [10][11][12][13][14] and boron nitride (BN, 4.5-5.5 eV), have been widely used in UV detection technology. 15,16 Owing to the characteristics of oxygen molecule adsorption and UV absorption, many wide-bandgap metal oxide materials, including zinc oxide (ZnO, 3.29 eV), 17,18 tungsten oxide (WO 3 , 2.6 eV), [19][20][21][22] stannic oxide (SnO 2 , 3.8 eV), 23,24 and titanium oxide (TiO 2 , 3.2 eV), 25,26 have also been extensively studied. Based on the different working principles, the UV semiconductor detector structures can be classified into the following types: Schottky barrier photodiodes, 27 photoconductors, 28 p-n or p-i-n junction types 29 and field-effect transistor-based structures.…”