Room‐Temperature Reversible and Nonvolatile Tunability of Electrical Properties of Cr‐Doped In2O3 Semiconductor Thin Films Gated by Ferroelectric Single Crystal and Ionic Liquid

Abstract

AbstractIntegration 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 × 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.