神经科学和神经工程研究需要研究大脑神经元的电活动情况，以了解大脑产生、传输和处理信息的机制。植入式神经微电极作为一种传感器件，是时间分辨率最高的神经电活动传感手段之一。介绍了国内外几种主要的植入式硅基神经微电极的结构特点、制备方法和性能特点。分析表明，未来通过不断结构优化和改性修饰，特别是在高通量的神经记录方面，通过与同样基于硅材料的电路的集成，硅神经微电极能够进一步提高生物相容性，解决大规模的电极通道体内外传输与连接问题，实现对神经元的在体大规模长时间记录。
The mechanisms by which the brain produces, transmits, and processes information are related with the neuroscience and the neural engineering, involving the electrical activity of brain neurons. As a kind of implantable sensor, the micro neural probe is one of the highest resolution tools used to record the neural activity. It can record electrical potentials of single neurons without damaging the nervous system. In order to record tens of billions of neurons in the brain, the more electrodes that can be simultaneously implanted, the more details of information processing by brain can be obtained. Thus, smaller volume and higher integration are required. As a kind of mature micro machining materials, silicon enjoys excellent mechanical properties and good biological compatibility. The neural microelectrode array fabricated from silicon has the advantages of small size, high integration and good electrical consistency. In this paper, the structure characteristics, the preparation methods and the performance of several mainstream implanted silicon based neural microelectrodes are reviewed. Through the continuous optimization of the structure, and the improvement of the modification methods and methods, the number of electrodes on one probe can be increased greatly, and the biocompatibility of the silicon based neural electrode be improved dramatically. In the area of high-throughput neural recording, the silicon based electrode fabricated with standard CMOS process and integrated with amplifier, as well as the analogue to digital circuit is a hopeful method to realize large-scale neural recording in-vivo,to replace the point to point connection between the electrode array in body and the recording equipment outside body with several digital lines.
[1] Barna J S, Arezzo J C, Jr Vaughan H G. A new multielectrode array for the simultaneous recording of field potentials and unit activity[J]. Electroencephalography & Clinical Neurophysiology, 1981, 52(5):494-496.
[2] Verloop A J, Holsheimer J. A simple method for the construction of electrode arrays[J]. Journal of Neuroscience Methods, 1984, 11(3):173-178.
[3] Krüger J, Bach M. Simultaneous recording with 30 microelectrodes in monkey visual cortex[J]. Experimental Brain Research, 1981, 41(2):191-194.
[4] Takahashi H, Suzurikawa J, Nakao M, et al. Easy-to-prepare assembly array of tungsten microelectrodes[J]. IEEE Transactions on Biomedical Engineering, 2005, 52(5):952-956.
[5] Fofonoff T, Martel S, Wiseman C, et al. A highly flexible manufacturing technique for microelectrode array fabrication[C/OL].[2017-06-30]. http://diyhpl.us/~bryan/papers2/neuro/implants/A%20highly%20flexible%20manufacturing%20technique%20for%20microelectrode%20array%20fabrication%20-%20Fofonoff2002preprint.pdf.
[6] Zhao S S, Pei W H, Hui Z, et al. A novel linear microprobe array for the fabrication of neural microelectrodes[J]. Science China Technological Sciences, 2015, 58(2):346-351.
[7] Campbell P K, Jones K E, Huber R J, et al. A silicon-based, three-dimensional neural interface:Manufacturing processes for an intracortical electrode array[J]. IEEE Transactions on Biomedical Engineering, 1991, 38(8):758-768.
[8] Normann R A, Maynard E M, Rousche P J, et al. A neural interface for a cortical vision prosthesis[J]. Vision Research, 1999, 39(15):2577-2587.
[9] Branner A, Normann R A. A multielectrode array for intrafascicular recording and stimulation in sciatic nerve of cats[J]. Brain Research Bulletin, 2000, 51(4):293-306.
[10] Bai Q, Wise K D, Anderson D J. A high-yield microassembly structure for three-dimensional microelectrode arrays[J]. IEEE Transactions on Bio-medical Engineering, 2000, 47(3):281-289.
[11] Najafi K, Wise K D. An implantable multielectrode array with on-chip signal processing[J]. IEEE Journal of Solid-State Circuits, 1986, 21(6):1035-1044.
[12] Chen S, Pei W, Gui Q, et al. PEDOT/MWCNT composite film coated microelectrode arrays for neural interface improvement[J]. Sensors & Actuators A Physical, 2013, 193(15):141-148.
[13] Lopez C M, Mitra S, Putzeys J, et al. 22.7 A 966-electrode neural probe with 384 configurable channels in 0.13μm SOI CMOS[C]//IEEE International Solid-State Circuits Conference. Piscataway, NJ:IEEE, 2016:392-393.
