Room-Temperature Reversible and Nonvolatile Tunability of Electrical Properties of Cr-Doped In2O3 Semiconductor Thin Films Gated by Ferroelectric Single Crystal and Ionic Liquid
Integration of different functional materials into a device in which the physical properties can be tuned using an electric field in a reversible and nonvolatile manner is highly desired for the fabrication of compact and energy-efficient multifunctional electronic devices. The integration of In2O3-based semiconductor thin films with ferroelectric 0.71PbMg1/3Nb2/3O3-0.29PbTiO3 (PMN-0.29PT) single crystals in ferroelectric-field-effect-transistor devices that allow for the tuning of carrier density, carrier type, Fermi level, and their related properties in a reversible and nonvolatile manner, is reported. Specifically, gating of In2-x Crx O3 (x = 0, 0.02, 0.05, 0.08, 0.11) films with a PMN-0.29PT layer provides a means to reversibly tune and modulate the resistivity of the films up to an on-and-off ratio of 5.2 x 104% in a nonvolatile manner at room temperature. Such resistivity modulation is associated with reversible and nonvolatile transformation of the carrier type between n-type and p-type due to polarization switching. Additionally, reversible switching of resistivity is realized utilizing DEME-TFSI ionic liquid as a top-gate material. These results demonstrate that electrical-voltage control of physical properties using PMN-xPT as both substrate and gating material provides a highly effective approach to study the carrier-density/type-related physical properties of semiconductor films.