Development of minimally invasive dry electrodes for recording biopotentials is presented. The detailed fabrication process is outlined. A dry electrode is formed by a number of microneedles. The lengths of the micron...Development of minimally invasive dry electrodes for recording biopotentials is presented. The detailed fabrication process is outlined. A dry electrode is formed by a number of microneedles. The lengths of the microneedles are about 150μm and the diameters are about 50μm. The tips of the microneedles are sharp enough to penetrate into the skin. The silver/silver chloride is grown on microneedle arrays and demonstrates good character. The electrocardiogram shows that the dry electrode is suitable for recording biopotentials.展开更多
A separate absorption,grading,charge and multiplication InGaAs/InP avalanche photodiode with ultra low dark current and high responsivity is demonstrated.It has a thin multiplication layer and a planar structure.Throu...A separate absorption,grading,charge and multiplication InGaAs/InP avalanche photodiode with ultra low dark current and high responsivity is demonstrated.It has a thin multiplication layer and a planar structure.Through the use of a well and a single floating guard ring to suppress edge breakdown,the device can easily be fabricated by one step epitaxial growth and one step diffusion.The dark current of a 30μm diameter device is as low as 0.028 nA at punch-through and 0.1 nA at 90%of the breakdown voltage.The responsivity at 1.55μm is 0.93 A/W at unity gain and the multiplication layer is estimated to be less than 300 nm.展开更多
基金Supported by the National Natural Science Foundation of China under Grant Nos 60776024, 60877035 and 90820002, tile National High-Technology Research and Development Program of China under Grant Nos 2007AA03Z427, 2007AA04Z329 and 2007AA04Z254.
文摘Development of minimally invasive dry electrodes for recording biopotentials is presented. The detailed fabrication process is outlined. A dry electrode is formed by a number of microneedles. The lengths of the microneedles are about 150μm and the diameters are about 50μm. The tips of the microneedles are sharp enough to penetrate into the skin. The silver/silver chloride is grown on microneedle arrays and demonstrates good character. The electrocardiogram shows that the dry electrode is suitable for recording biopotentials.
基金Supported by the National Natural Science Foundation of China under Grant Nos 61176053,61274069,61021003the National Key Basic Research Program of China under Grant No 2012CB933503the National High-Technology Research and Development Program of China under Grant No 2012AA012202.
文摘A separate absorption,grading,charge and multiplication InGaAs/InP avalanche photodiode with ultra low dark current and high responsivity is demonstrated.It has a thin multiplication layer and a planar structure.Through the use of a well and a single floating guard ring to suppress edge breakdown,the device can easily be fabricated by one step epitaxial growth and one step diffusion.The dark current of a 30μm diameter device is as low as 0.028 nA at punch-through and 0.1 nA at 90%of the breakdown voltage.The responsivity at 1.55μm is 0.93 A/W at unity gain and the multiplication layer is estimated to be less than 300 nm.
