Organic-inorganic hybrid perovskites (OHP), described by ABX3 (A = organic cation, B = metal cation, X = halogen anion) has attracted much attention as a candidate material for future solar-cell applications with easy-fabrication, low-cost, and high-efficiency. Therefore, OHP materials are motivated not only to enhance performance for solar-cell application but also to bring to light new phenomena relevant to other technological application such as light emitting diode, laser, optoelectronics and thermos electronics, among others.
We performed the systematic experiment with different inorganic material first layer deposition rates to confirm the quality of thin films fabricated by the sequential vacuum evaporation method (SVE) method. As the deposition rate was increased, the hybrid perovskite forms well. However, we found the tiny grain and the intermediate state, and the molecular defect is observed. From these findings, we speculate why a vacuumevaporated OHP-based solar-cell has relatively low PCE and material instability.