Cr纳米粒子密集点阵应变传感器的制备与传感特性研究

发布时间：2018-05-23 23:31

  本文选题：金属纳米粒子点阵 + 量子输运　； 参考：《南京大学》2015年硕士论文

【摘要】：金属纳米粒子点阵中电子的传输机制不同于经典接触式的欧姆输运模式,而是以量子输运的形式进行的。在这种输运模式下,纳米粒子点阵的电导率对粒子间距的变化极其敏感。这导致了粒子间距的细微改变就会使材料整体的电导率产生较大变化。根据这一特点,弹性衬底表面制备电极并覆盖金属纳米粒子点阵,能够得到新型的应变传感器。本论文研究基于金属Cr纳米粒子点阵的应变传感器的制备与传感特性。论文采用团簇束流沉积制备Cr纳米粒子点阵,通过对沉积过程的实时电导监控,实现对纳米粒子点阵覆盖率与初始电导的精确控制。选择PET薄膜并在其上通过掩模蒸发镀膜制作叉指电极作为衬底,在其上制备可控密度的Cr纳米粒子点阵构成应变传感器。对金属Cr纳米粒子点阵的变温Ⅰ-Ⅴ曲线与电导测量表明,硅衬底上的Cr纳米粒子点阵,直至室温都能够观察到明显的库伦阻塞效应,而在PET衬底上的Cr纳米粒子点阵中,即使在低温下,也未库伦阻塞现象,可能是PET衬底较大的热胀冷缩效应导致的纳米粒子间距的变化掩盖了温度变化对量子电导的影响。但两种衬底上测量的Cr纳米粒子点阵的电导-温度曲线,都呈现不同于块状金属材料的负电阻温度系数,表明其电导都起源于量子输运。本文研究了Cr纳米粒子点阵应变传感器对不同形式应变的响应特性。在拉伸测试中,传感器的电导变化与应变呈现了良好的线性关系,在弹性范围内,传感器的灵敏度系数可达6.1,优于金属应变片。在弯曲测试中,传感器的电导变化与应变呈现指数关系,具有优异的灵敏度系数,在应变为0.16%以内,灵敏度系数可达到40以上。传感器也具有大的量程,最大应变能够达到3%,对应的灵敏度系数最高可达到近3000。在压强测试中,Cr纳米粒子点阵传感器显示了在大气压强附近进行Pa量级高精度压力测量的能力,可用于高精度大气气压监测、新一代车载导航、个人气象站等应用。本文还研究了纳米粒子覆盖率对所构成应变传感器的灵敏度系数的影响,实验表明,在覆盖率已达到渗流阈值的样品中,纳米粒子覆盖率越低,应变响应的灵敏度系数越高。
[Abstract]:The mechanism of electron transport in metal nanoparticles lattice is different from the classical contact ohmic transport mode, but in the form of quantum transport. In this transport mode, the conductivity of nanoparticle lattice is very sensitive to the change of particle spacing. This leads to a slight change in the spacing of particles, resulting in a significant change in the overall conductivity of the material. According to this characteristic, a new strain sensor can be obtained by fabricating electrodes on the surface of elastic substrates and covering metal nanoparticles with lattice. In this paper, the fabrication and sensing characteristics of strain sensors based on metal Cr nanoparticles lattice are studied. In this paper, Cr nanoparticles lattice was prepared by cluster beam deposition, and the coverage and initial conductance of nano-particles were accurately controlled by monitoring the deposition process in real time. Cross finger electrode was fabricated on PET thin film by mask evaporation, on which Cr nanocrystalline lattice with controllable density was fabricated to form strain sensor. The variable-temperature I-鈪，

本文编号：1926818