Characterization and analysis of structural and optical properties of perovskite thin films

The development of perovskite thin films by spin-coating, deposition techniques have been investigated. The methyl ammonium lead iodide (CH₃NH₃PbI₃) perovskite has a direct band gap of 1.5 eV and a large absorption coefficient of over 104 cm^-1. The perovskite absorber was deposited by a non-vacuum liquid-based coating method with chlorobenzene and without chlorobenzene by using Laurell Technologies WS650 spin processor. Optical, structural and electronic characterization and analysis of the thin films were performed by using the Hitachi S-4800 Scanning Electron Microscope (SEM) and the Bruker D8 Discover X-ray diffractometer (XRD), the Thermo Scientific DXR SmartRaman spectrometer, and the Cary 5000 UV-Vis spectrophotometer. Results were used to determine the crystal structure, orientation and crystallite size, and energy band gap (Eg) of perovskite thin films.