Effect of annealing on the structural, morphological and optical properties of Ga-doped ZnO nanoparticles by reflux precipitation method

Magnetron Sputtering for ZnO:Ga Scintillation Film Production and Its Application Research Status in Nuclear Detection

“…Lower annealing temperature does not change the defect distribution in the films [112], but the intensity of ultraviolet emission band increases and no visible light emission can be detected [120]. When the annealing temperature increases to a higher temperature range, the blue peak shifts obviously towards the long wavelength, and the green luminescence peak begins to appear, although it is very weak compared to the strong ultraviolet emission [121]. It was considered that thin films annealed under an unstable state would cause more defects and lead to the fluctuation between UV and visible emission [122].…”

“…It was considered that thin films annealed under an unstable state would cause more defects and lead to the fluctuation between UV and visible emission [122]. As the annealing temperature continues to rise, the UV emission begins to weaken and the green emission keeps increasing [121]. For higher carrier concentration, the auger effect will be produced to quench the luminescence, this is called concentration quenching [123].…”

“…Annealing is a recrystallization process in a proper temperature range, which helps to reduce defects, especially in an oxygen atmosphere. Annealing treatment helps to enhance the light radiation based on band-edge transition due to the reduction of V O defects in ZnO:Ga films and the more complete crystallization of the films [121]. As for the annealing conditions, the annealing atmosphere is also an important factor as well as temperature.…”

“…reduction of VO defects in ZnO:Ga films and the more complete crystallization of the films [121]. As for the annealing conditions, the annealing atmosphere is also an important factor as well as temperature.…”

“…Considering that the bond length of Al-O is 0.27 nm and the bond length of In-O is 0.21 nm, Ga is the best doping element of ZnO-n type [20]. Doping Ga can effectively reduce the lattice's distortion due to the high concentration doping, thus the crystal quality of thin films can be improved [21]. [16].…”