Controllable Modulation of the Electronic Properties of a Two-Dimensional Ambipolar Semiconductor by Interface Ferroelectric Polarization

Kunrong Du; Ziyuan Meng; Yilian Xi; Nana Liu; Jingwei Zhang; Shengjie Xu; Zhijian Shi; Hongrun Zhang; Shan Wang; Haifeng Feng; Weichang Hao; Hui Pan; Shujun Zhang; Yi Du

doi:10.1021/acsami.3c15191

Controllable Modulation of the Electronic Properties of a Two-Dimensional Ambipolar Semiconductor by Interface Ferroelectric Polarization

ACS Appl Mater Interfaces. 2024 Jan 24;16(3):4181-4188. doi: 10.1021/acsami.3c15191. Epub 2024 Jan 9.

Authors

Kunrong Du^{1

2}, Ziyuan Meng^{1

2}, Yilian Xi^{1

2}, Nana Liu^{1

2}, Jingwei Zhang^{1

2}, Shengjie Xu^{1

2}, Zhijian Shi^{1

2}, Hongrun Zhang^{1

2}, Shan Wang^{1

2}, Haifeng Feng^{1

2}, Weichang Hao^{1

2}, Hui Pan¹, Shujun Zhang³, Yi Du^{1

2}

Affiliations

¹ School of Physics, Beihang University, Beijing 100191, P. R. China.
² Centre of Quantum and Matter Sciences, International Research Institute for Multidisciplinary Science, Beihang University, Beijing 100191, P. R. China.
³ Institute for Superconducting and Electronic Materials, Australian Institute of Innovative Materials, University of Wollongong, Wollongong 2522, New South Wales, Australia.

PMID: 38194269
DOI: 10.1021/acsami.3c15191

Abstract

Precise control of charge carrier type and density of two-dimensional (2D) ambipolar semiconductors is the prerequisite for their applications in next-generation integrated circuits and electronic devices. Here, by fabricating a heterointerface between a 2D ambipolar semiconductor (hydrogenated germanene, GeH) and a ferroelectric substrate (PbMg_1/3Nb_2/3O₃-PbTiO₃, PMN-PT), fine-tuning of charge carrier type and density of GeH is achieved. Due to ambipolar properties, proper band gap, and high carrier mobility of GeH, by applying the opposite local bias (±8 V), a lateral polarization in GeH is constructed with a change of work function by 0.6 eV. Besides, the built-in polarization in GeH nanoflake could promote the separation of photoexcited electron-hole pairs, which lead to 4 times enhancement of the photoconductivity after poling by 200 V. In addition, a gradient regulation of the work function of GeH from 4.94 to 5.21 eV by adjusting the local substrate polarization is demonstrated, which could be used for data storage at the micrometer size by forming p-n homojunctions. This work of constructing such heterointerfaces provides a pathway for applying 2D ambipolar semiconductors in nonvolatile memory devices, photoelectronic devices, and next-generation integrated circuit.

Keywords: 2D ambipolar semiconductor; data storage device; ferroelectric substrate; hydrogenated germanene; photoelectronic device; scanning probe microscopy.