Excellent Bipolar Resistive Switching Characteristics of Bi4Ti3O12 Thin Films Prepared via Sol-Gel Process.

He-Chun Zhou,Zhen-Hua Tang,Yan-Ping Jiang,Qiu-Xiang Liu,Wen-Hua Li,Xin-Gui Tang

doi:10.3390/nano11102705

He-Chun Zhou, Zhen-Hua Tang + Show 4 more

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https://doi.org/10.3390/nano11102705

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Abstract

Herein, Bi4Ti3O12 (BIT) ferroelectric thin films were fabricated into Au/BIT/LaNiO3/Si structures to demonstrate their memristor properties. Repeatable and stable bipolar resistive switching (RS) characteristics of the device are first reported in this work. The switching ratio of the device annealed in air reached approximately 102 at 0.1 and −0.1 V. The RS performance was not significantly degraded after 100 consecutive cycles of testing. We also explored the factors affecting the RS behavior of the device. By investigating the RS characteristics of the devices annealed in O2, and in combination with XPS analysis, we found that the RS properties were closely related to the presence of oxygen vacancies. The devices annealed in air exhibited a markedly improved RS effect over those annealed in O2. According to the slope fitting, the conduction mechanism of the device was the ohmic conduction and space charge limited current (SCLC). This study is the first to successfully apply BIT ferroelectric films to the RS layers of memristors. Additionally, a theory of conductive filaments is proposed to adequately explain the relationship between RS behavior and oxygen vacancies, providing meaningful inspiration for designing high-quality resistive random access memory devices.

Highlights

BIT thin films grown on LNO/p-Si substrates were prepared via the sol-gel process
We found that a larger ratio of RHRS /RLRS can be obtained at smaller voltages of −0.1 V and 0.1 V
The results show content be defined as the content oxygen vacancies

Summary

Introduction

Several competitive non-volatile memories have been developed, including but not limited to phase change, magnetic, ferroelectric, and resistive random-access memory (RRAM) [7,8,9]. Simple structure, high-endurance cycles, fast operation, and high-density data storage, RRAM is considered an ideal candidate to meet the demands for the promising non-volatile memory of the future. One of the most significant advantages of a typical RRAM lies in its simple metal-insulator-metal (MIM) device structure, in which resistive switching (RS) layers are sandwiched between two metal electrodes. When the bias polarity or voltage amplitude is stimulated, RRAM can electrically change its resistance state between a high-resistance state (HRS) and low-resistance state (LRS) to complete the storage of information [12,13].

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