Temperature dependence of MAPbI3 films by quasi-vapor deposition technique and impact on photovoltaic performance and stability of perovskite solar cells

Abstract Perovskite solar cells (PSC) have been a major focus in the photovoltaic community because of their high efficiency within a decade. The performance and stability of PSCs are highly dependent on the perovskite layer deposition and film quality. However, the solution processing techniques are still lacking to produce high-quality perovskite films for large scale device fabrication. In this work, a high-quality and uniform MAPbI3 perovskite films are developed by quasi-vapor deposition (QVD) at low temperature, low working pressure, with short reaction time and without post annealing. The substrate temperature is varied from 70 °C to 130 °C during the deposition in order to study the film uniformity, morphology and its influence on PSCs. MAPbI3 films deposited at 100 °C showed uniform film with grain size of 375 nm and the PSCs prepared with the film exhibited the highest power conversion efficiency (PCE) of 15.6%. Simultaneously, PSC prepared with the solution process exhibited PCE of 12.0% with poor ambient stability than the QVD processed devices. The results will provide a new pathway for developing high quality and large scale device with high performance and stability.