Effect of high-temperature post-deposition annealing on cesium lead bromide thin films deposited by vacuum evaporation

The effects of high-temperature (500 degrees C) post-deposition annealing (PDA) on the properties of cesium lead bromide (CsPbBr3) films deposited by vacuum evaporation were studied. The PDA effectively improved the grain size of the CsPbBr3 films. This improvement of the grain size leads to the improvement of carrier diffusion length from 0.1 mu m to 0.5 mu m. A CsPbBr3 solar cell fabricated using a CsPbBr3 layer with PDA at 500 degrees C for 60 min showed a conversion efficiency of 6.62% (V-OC = 1.465 V, J(SC) = 6.57 mA/cm(2), and FF = 0.688). Our CsPbB3 solar cell also showed a conversion efficiency of 22.5% (V-OC = 1.502 V, J(SC) = 53.7 mA/cm(2), and FF = 0.574) for blue LED light (peak wavelength of 453 nm) with an intensity of 206 mW/cm(2).