View article

CH 3 NH 3 PbI 3 thin films were formed with various deposition rates of PbI 2 first layer using a sequential vacuum evaporation method (SVE) to understand the formation behavior. Under low PbI 2 deposition rates with 1 and 3 Å s− 1, the thin films did not form the hybrid perovskite structure. Over the 6 Å s− 1 deposition rate, the perovskite structure is observed with the remaining PbI 2 and an intermediate phase together. In the 10 Å s− 1, the intermediate phase is increased, and the CH 3 NH 2 molecular defect is observed. The hybrid perovskite thin film formed by SVE is confirmed with tiny grains and CH 3 NH 2-incorporated intermediate state.