摘要
设计了一种新型的脑电图干电极,主要用于采集脑电信号以进行基于脑电图的警觉度分析,替代传统的湿电极.采用柔性衬底微电子机械系统(MEMS)加工技术,在柔性衬底上制备出具有化学稳定性与生物相容性的微针状干电极阵列.通过铜牺牲层实现干电极微针的悬臂梁结构,利用聚二甲基硅氧烷(PDMS)剥离层实现器件从玻璃基底的完全释放,并经平面电极的多层组装实现了立体电极阵列.实验中干电极以聚酰亚胺作为柔性衬底,其针端及导线部分材料为镍,针端部分表面镀金.采用Neuroscan的脑电信号采集放大器对干电极性能进行了测试,测得阻抗约为10kΩ,其时域和频域信号与传统湿电极基本一致.所制备的干电极成品率高、尺寸小、屏蔽佳、装配简单、可靠性好、机械强度大,符合快速、无痛的脑电信号采集要求.
A novel dry electroencephalography（EEG） electrode was fabricated for the vigilance analysis based on EEG signal acquisition,which is conventionally acquired by wet electrodes.Flexible substrate MEMS fabrication technique was applied to fabricate the flexible dry micro-needle electrode array,which is chemical stable and bio-compatible.Featuring its cantilever structured micro-needles,the electrode was fabricated by wet etching of Cu sacrificial layer process.The electrodes were then released from substrate by PDMS lift-off process and packaged by polyimide,and finally fabricated a three-dimensional electrode array by multi-layer assembly.Ni was electroplated to fabricate the micro-needles,the wire and the pads of the dry electrode to obtain mechanical strength while Au was electroplated on the surface of micro-needles for bio-compatibility.The performance of the dry electrode was tested by the amplifier of EEG acquisition,Neuroscan.The impedance of dry electrode was approximately 10 kΩ,and the similarity between the performances of dry and wet electrodes was proved by comparison of their time domain and frequency domain signals.With the advantage of high yield,small size,simple assembly,fine shielding,good reliability and mechanical strength,the dry electrode is capable of convenient and painless EEG signal acquisition.
出处
《上海交通大学学报》
EI
CAS
CSCD
北大核心
2011年第7期1035-1040,共6页
Journal of Shanghai Jiaotong University
基金
上海市科学技术委员会资助项目(09511502400)
关键词
干电极阵列
柔性衬底
微电子机械系统技术
多层组装
脑电图
dry electrode array
flexible substrate
microeletro mechanical system（MEMS） technique
multi-layer assembly
electroencephalography（EEG）
