High field-effect hole mobility in organic-inorganic hybrid thin films prepared by vacuum vapor deposition technique

Organic-inorganic layered perovskite films, (C₆H ₅C₂H₄NH₃)₂SnI ₄, were grown on 60°C substrates at a growth rate of 0.0005 nm/s by a vacuum vapor deposition technique, and field-effect transistors with a hybrid semiconductor were fabricated. From measurements of ultraviolet-visible (UV-VIS) absorption spectra and X-ray diffraction profiles, the vacuum-deposited films contained a well-developed layered perovskite structure, where inorganic sheets alternate with organic layers in the direction perpendicular to the substrate surface. In the field-effect transistors, the vacuum-deposited hybrid films acted as p-channel semiconductors and exhibited a hole mobility of 0.78cm²/Vs in the saturation regime, a threshold voltage of -1.7V, and a drain current on/off ratio of 4.2 × 10⁵.