【作者】 赵本刚；

【导师】 吴亚明；

【作者基本信息】 中国科学院研究生院（上海微系统与信息技术研究所） ， 微电子学与固体电子学， 2007， 博士

【摘要】 高压大电流和微纳安电流的测量是电流传感器领域中的两个重要应用方向，这两类电流信号难以直接测量，必须对其信号进行处理、变换才能达到精确测量的目的。光学电流传感器与传统的电流互感器相比具有很多优点，但在实际应用中还受到多种因素的制约，其中温度引起的精度问题和传感头老化问题最为明显，目前还正处于研究和试验阶段。对于微纳安电流的测量，通常采用将输入电流进行放大的电路检测法，然而放大器对输入信号放大的同时也对干扰噪声进行放大，使测量结果产生较大的影响。结合MEMS技术可大批量、高一致性、低成本的加工特点和光纤传感技术，本论文提出了基于MEMS的光学电流传感器(MEMS-OCS)和微纳安检流计，主要进行了如下的研究工作：(1)针对频率50Hz几百到几千安培范围内高压电流的电力工业测量需求，论文首次提出由Rogowski线圈、MEMS扭转微镜和双光纤准直器构成的光学电流传感器探测头，通过电阻的温度补偿设计，MEMS-OCS可以满足0.2％—0.6％的精度要求，同时探测头不存在老化问题，是一种具有实用价值的光学电流传感器；(2)针对纳安到微安范围电流的测试需求，论文首次设计并制作了MEMS微纳安检流计。该检流计在纳安级电流不直接放大的情况下，由MEMS扭转微镜和双光纤准直器构成的探测头进行直接测量，从而避免了电路中放大器带来的噪声干扰问题，是一种新颖的器件，具有广阔的应用前景；(3)论文运用Mathcad、Matlab数值计算和ANSYSY有限元分析相结合，仿真模拟了MEMS扭转微镜在感应电流驱动下的静态、动态、热膨胀、应力等特性，完成了MEMS光学电流传感器和微纳安检流计的优化设计和性能模拟；(4)论文详细研究了用于光学电流传感器和微纳安检流计的扭转微镜制作工艺，对KOH深腐蚀后硅表面粗糙度的改善、引线的制作、绝缘层的选择与刻蚀、微米量级悬臂梁的刻蚀与保护等几个关键工艺做了相应的研究与改进，成功制作了微米量级悬臂梁的扭转微镜；(5)论文对MEMS光学电流传感器和微纳安检流计的性能进行了测试。测试结果表明：MEMS光学电流传感器的性能较好，灵敏度可达到2.5 mV／A；微纳安检流计的灵敏度为0.81dB／μA，直接测量的分辨力可以达到6.5nA，并对实验结果进行了分析。更多还原

【Abstract】 The measurement of high voltage current and microampere/nanoampere are two important application directions in the field of current sensor, the two types of current are difficult to be tested directly, so the input signal must be processed and transformed before accurate measurement. Compared to traditional current transformers, optical current sensors (OCSs) have many advantages, but they are restricted by many factors in practical application, especially the precision caused by temperature and aging of sensing head, so OCSs still stay at the stage of theory research and experiment. Amplifier circuit is mostly used in the measurement of microampere/nanoampere current, but noise and the input signal are synchronously amplified, which will bring the measurement errors.Based on optic fiber sensing technology and the characteristics of MEMS technology, such as mass production, high consistency and low cost, optical current sensor and microampere/nanoampere galvanometer (MNG) based on MEMS are researched in this thesis. The main contents are summarized as follows:(1) For the measurement of 50Hz high voltage current with peak value from hundreds to thousands ampere, the OCS sensing head composed of Rogowski coils, torsional micro-mirror and dual fiber collimator is proposed firstly. MEMS -OCS is a practical optical current sensor, which meets the requirement of 0.2%—0.6% precision and solves the problem of sensing head aging.(2) For the measurement of current within nanoampere to microampere, the galvanometer based on MEMS is studied firstly. The nanoampere current can be directly measured by the sensing head composed of torsional micro-mirror and dual fiber collimator, which eliminates the noise of the amplifier in the circuit, so MNG is a novel sensor for practical application. (3) With numerical calculation of Mathcad、Matlab and finite element analysis of ANSYS ,static analysis, dynamic response, heat expansion and stress of micro-mirror driven by induction current are analyzed and simulated, the optimized design and performance simulation of OCS and MNG are successfully finished.(4) The fabrication process of torsional micro-mirrors for OCS and MNG are detailedly explained. The most important process steps, such as the roughness improvement of silicon surface after etched by KOH, fabrication of lead wire, selection and etching of insulating layer, etching and protection of micrometer cantilever beam, are researched and improved, so the micro-mirrors with micrometer cantilever beam can be successfully fabricated.(5) The performance of OCS and MNG are tested in the laboratory. The results show: the sensitivity of OCS can reach 2.5 mV/A; the sensitivity of MNG is 0.81dB/μA, and the resolution of MNG can reach 6.5 nA. The experimental results are analyzed.更多还原