Аннотация:
We present investigations on the growth of high quality CH3NH3PbI3 (MAPI) thin films using both vapor and
solution techniques. Recent work on perovskite film growth indicates critical dependencies of the film quality on the
nucleation and crystallization steps requiring: i.) uniform distribution of nucleation sites; and ii.) optimal
crystallization rate that facilitates the growth of a compact, continuous film with low density of pinholes. Our work
shows that the hybrid chemical vapor deposition technique (HCVD) technique is well suited for the deposition of
evenly distributed nucleation sites and the optimization of the crystallization rate of the film through detailed
monitoring of the thermal profile of the growth process. Signficant reduction in the defect states is recorded by
annealing the perovskite films in O2. The results are consistent with theoretical studies by Yin et al.1 on O and Cl
passivation of the shallow states at the grain boundary of MAPI. Their work provides the theoretical basis for our
experimental observations on the passivation of shallow states by oxygen annealing. High quality films were
achieved through detailed management of the carrier gas composition and the thermal profile of the nucleation and
crystallization steps.