Engineering of self-rectifying filamentary resistive switching in LiNbO3 single crystalline thin film via strain doping

Tiangui You,Jiajie Lin,Min Zhou,Kai Huang,Xin Ou,Ailun Yi,Xiaomeng Zhao,Wei Ren,Wenbo Luo,Tingting Jin,Yao Shuai,Wenjie Yu,Chen Chen

doi:10.1038/s41598-019-55628-3

Abstract

The abilities to fabricate wafer scale single crystalline oxide thin films on metallic substrates and to locally engineer their resistive switching characteristics not only contribute to the fundamental investigations of the resistive switching mechanism but also promote the practical applications of resistive switching devices. Here, wafer scale LiNbO3 (LNO) single crystalline thin films are fabricated on Pt/SiO2/LNO substrates by ion slicing with wafer bonding. The lattice strain of the LNO single crystalline thin films can be tuned by He implantation as indicated by XRD measurements. After He implantation, the LNO single crystalline thin films show self-rectifying filamentary resistive switching behaviors, which is interpreted by a model that the local conductive filaments only connect/disconnect with the bottom interface while the top interface maintains the Schottky contact. Thanks to the homogeneous distribution of defects in single crystalline thin films, highly reproducible and uniform self-rectifying resistive switching with large on/off ratio over four order of magnitude was achieved. Multilevel resistive switching can be obtained by varying the compliance current or by using different magnitude of writing voltage.

Highlights

Due to the advantages of high-speed switching, large scalability, low energy consumption and multi-bit memory, resistive switching devices, comprised of a semiconductor sandwiched with metallic electrodes, are considered as one of the leading candidates for the generation nonvolatile memories known as resistive random access memories (ReRAM)[1,2]
It is noted that there is no lattice matching relationship between the transferred LNO thin films and the LNO holding substrate prepared by ion slicing with wafer bonding, which is different from the case of the traditional thin film growth
Wafer scale LNO single crystalline thin films have been prepared on Pt/SiO2/LNO substrates by ion slicing with wafer bonding

Summary

Introduction

Due to the advantages of high-speed switching, large scalability, low energy consumption and multi-bit memory, resistive switching devices, comprised of a semiconductor (or insulator) sandwiched with metallic electrodes, are considered as one of the leading candidates for the generation nonvolatile memories known as resistive random access memories (ReRAM)[1,2]. Introducing a slight lattice constant modification by noble gas implantation has been proved to be an effective approach to locally tailor the physical properties in semiconductors or functional oxides, e.g., the electronic transport and ferroelectric switching in BiFeO3 thin films can be engineered via He implantation[35]. This approach was recognized as “strain doping”[36,37]. The lattice strain in LNO single crystalline thin films can be engineered by strain doping via He implantation, and highly reproducible and uniform resistive switching with self-rectifying, large on/off ratio and multi-level switching was obtained

Methods

Results

Conclusion