Lead iodide thin-film morphological-dependent metastability investigation by electrical conductivity

This study describes the metastability properties of lead iodide (PbI2) thin films which were deposited by thermal chemical vapor deposition (CVD) and spin coating on ultrasonically and chemically cleaned microscope glass substrates. Morphological differences due to deposition techniques were defined by scanning electron microscopy (SEM). Deposited PbI2 thin films have been exposed to laboratory atmosphere ambient, vacuum, and enhanced deionize water vapor (EDIWV) in order to define metastability changes. Samples metastability changes have been investigated by current-voltage (I-V), time-dependent conductivity, and annealing cycle method depending on atmospheric conditions. Activation energy of PbI2 thin films was calculated from temperature-dependent dark conductivity. Based on results gathered from this work, degradation of PbI2 dependent on atmospheric condition and surface morphology with the aspect of meta/instability view has been tried to analyzed.