A switchable high-sensitivity strain sensor based on piezotronic resonant tunneling junctions  

作　　者：Gongwei Hu Li Zeng Fobao Huang Shuaiwei Fan Qiao Chen Wei Huang 

机构地区：[1]Hubei Engineering Research Center of Weak Magnetic-field Detection, Department of Physics, China Three Gorges University, Yichang, 443002, China [2]School of Microelectronics, Northwestern Polytechnical University, Xi’an, 710072, China [3]Institute of Flexible Electronics, Northwestern Polytechnical University, Xi’an, 710072, China [4]School of Computational Science and Electronics, Hunan Institute of Engineering, Xiangtan, 411104, China

出　　处：《Nano Research》2024年第11期10242-10255,共14页纳米研究（英文版）

基　　金：supported from the National Natural Science Foundation of China(No.62404125);the Hubei Provincial Natural Science Foundation of China(No.2024AFB359);the Yichang City Natural Science Foundation of China(No.A24-3-004);the China Three Gorges University(No.2023RCKJ0035);the Basic Research Programs of Taicang,2021(No.TC2021JC20);the China Postdoctoral Science Foundation(No.2022M722588);the Young Talent Fund of Xi’an Association for Science and Technology(No.959202313090);the Key Research and Development Projects of Shaanxi Province(No.2024GX-YBXM-029).

摘　　要：Developing emerging technologies in Internet of Things and artificial intelligence requires high-speed, low-power, high-sensitivity, and switchable-functionality strain sensors capable of sensing subtle mechanical stimuli in complex ambience. Resonant tunneling diodes (RTDs) are the good candidate for such sensing applications due to the ultrafast transport process, lower tunneling current, and negative differential resistance. However, notably enhancing sensing sensitivity remains one of the greatest challenges for RTD-related strain sensors. Here, we use piezotronic effect to improve sensing performance of strain sensors in double-barrier ZnO nanowire RTDs. This strain sensor not only possesses an ultrahigh gauge factor (GF) 390 GPa^(−1), two orders of magnitude higher than these reported RTD-based strain sensors, but also can switch the sensitivity with a GF ratio of 160 by adjusting bias voltage in a small range of 0.2 V. By employing Landauer–Büttiker quantum transport theory, we uncover two primary factors governing piezotronic modulation of resonant tunneling transport, i.e., the strain-mediated polarization field for manipulation of quantized subband levels, and the interfacial polarization charges for adjustment of space charge region. These two mechanisms enable strain to induce the negative differential resistance, amplify the peak-valley current ratio, and diminish the resonant bias voltage. These performances can be engineered by the regulation of bias voltage, temperature, and device architectures. Moreover, a strain sensor capable of electrically switching sensing performance within sensitive and insensitive regimes is proposed. This study not only offers a deep insight into piezotronic modulation of resonant tunneling physics, but also advances the RTD towards highly sensitive and multifunctional sensor applications.

关 键 词：piezotronic effect resonant tunneling diode negative differential resistance highly sensitive strain sensor ZnO nanowire ratio of gauge factor 

分 类 号：TP212[自动化与计算机技术—检测技术与自动化装置]