Effect of Pr concentration and native defects on the structural, electronic and optical properties of Pr doped IZO by first-principles study

Praseodymium (Pr) doped IZO was reported as an effective means to enhance the NBIS stability of AOS TFTs without sacrificing other electrical properties, which is expected to promote the commercial application of IZO in the display fields. However, the Pr concentration and the role of point defects of Pr-doped IZO on the performance is unclear. To solve the problem, the influence of Pr concentrations and vacancies on the structural, electronic and optical properties of In2Zn3O6 (IZO) doped with Pr was investigated by the first-principles calculations. The structural optimization calculated results show that the Pr atoms prefer to replace In atoms in comparison to the Zn atoms in IZO cell, and the VZn is easier to be generated than VIn and VO in Pr-doped IZO. Furthermore, the calculated band gap and carrier effective mass results of pure IZO, 1.67 at% Pr-IZO, 3.33 at% Pr-IZO and 6.67 at% Pr-IZO indicated that the best conductivity and stability can be obtained with smallest amount of Pr doping (1.67 at%). Additionally, the point defects will obvious effects on the shape of the band structures and controlling vacancies, which is a key strategy of regulating electrical performance. Finally, it is found that doping Pr in IZO can obtain a higher transmittance with a blue shift trends in the direction of visible light and introducing the point defects is also an effective way to reduce the transmittance property of Pr-IZO in the energy of infrared region.