The potential of the vapor-phase deposition of metal halide perovskites (MHPs) for solar cells remains largely untapped, particularly in achieving rapid deposition rates. In this study, we employ in situ photoluminescence (PL) to monitor the growth dynamics of MHPs deposited via pulsed laser deposition (PLD), with rates ranging from 6 to 80 nm/min. Remarkably, the PL intensity evolution remains consistent across both low- and high-deposition rates, indicating that increased deposition rates do not significantly alter the fundamental mechanisms driving MHP formation via PLD. However, microstructural analysis and time-resolved microwave conductivity (TRMC) measurements reveal that increasing deposition rates lead to randomly oriented films on contact layers and reduced charge mobility compared with films grown at lower deposition rates. These findings emphasize the critical role of controlling initial nucleation and the value of in situ PL monitoring in optimizing the vapor-phase deposition of MHPs for enhanced photovoltaic performance at high deposition rates.

The ongoing development of photovoltaics into terawatt scale poses a number of challenges where the optics and photonics communities can contribute. An international consortium recently compiled a roadmap that elaborates on these challenges.