Vertical Organic-Inorganic Hybrid Perovskite Schottky Junction Transistors

While organolead halide perovskite materials have attracted considerable attention for high efficiency solar cells, they have shown little potential for use in field-effect transistors (FETs) due to the limited current modulation at room temperature. Here, by developing a vertically gated methylammonium lead iodide (MAPbI(3))/indium-tin oxide (ITO) Schottky junction, a room temperature-operable vertical MAPbI(3) thin-film transistor is reported. Due to the injection-controlled gating mechanism as well as the vertical channel structure, a current modulation ratio up to 10(4) is achieved. Fabrication of a nanoporous ITO source electrode forming a highly rectifying Schottky junction with the MAPbI(3) layer is the key for the large current modulation. It is discovered that the electron transporting layers on top of the MAPbI(3) layer play an important role in achieving a large current rectification of 10(7) at the Schottky junction and hence large current on/off ratios of the resulting transistor.