The delicate serpentine structures are widely used in high-performance stretchable electronics over the past decade.The metal interconnects encapsulated in biocompatible polymer Parylene-C film is a superior choice fo...The delicate serpentine structures are widely used in high-performance stretchable electronics over the past decade.The metal interconnects encapsulated in biocompatible polymer Parylene-C film is a superior choice for long-term implantation in vivo,especially as neural interface to acquire electrophysiological signals or apply electrical stimulation.To avoid the physical contact damages from the neural tissues such as the brain or peripheral nerves,serpentine interconnects are utilized as stretchable electrodes and usually bonded to the soft elastomer substrate.The adhesion strength between the serpentine interconnects and the elastomer substrate becomes a considerable issue to ensure reliability and structural integrity.In this paper,the stretchable Parylene-C electrodes can be transfer printed onto arbitrary elastomer substrates by a thin layer of silicone rubber adhesive with low modulus for electrocorticogram(ECoG)recording.Mechanical simulation of serpentine structures consisting of same periodic arcs and different straight segments is investigated by uniaxial stretching.Then,the elastic stretchability of serpentine electrodes is further studied by simulation and experiments.After 5000 repetitive stretching cycles,the electrochemical impedance of microelectrodes remains in steady states.These results prove that the silicone rubber adhesive facilitates the interfacial bonding in the structure of stretchable electrodes as the compliant and reliable neural interface.展开更多
Light management and electrical isolation are essential for the majority of optoelectronic nanowire （NW） devices. Here, we present a cost-effective technique, based on vapor-phase deposition of parylene-C and subseq...Light management and electrical isolation are essential for the majority of optoelectronic nanowire （NW） devices. Here, we present a cost-effective technique, based on vapor-phase deposition of parylene-C and subsequent annealing, that provides conformal encapsulation, anti-reflective coating, improved optical properties, and electrical insulation for GaAs nanowires. The process presented allows facile encapsulation and insulation that is suitable for any nanowire structure. In particular, the parylene-C encapsulation functions as an efficient antireflection coating for the nanowires, with reflectivity down to 〈1% in the visible spectrum. Furthermore, the parylene-C coating increases photoluminescence intensity, suggesting improved light guiding to the NWs. Finally, based on this process, a NW LED was fabricated, which showed good diode performance and a clear electroluminescence signal. We believe the process can expand the fabrication possibilities and improve the devices. performance of optoelectronic nanowire展开更多
In this paper, a silicon-based neural probe with microfluidic channels was developed and evaluated. The probe can deliver chemicals or drugs to the target neurons while simultaneously recording the electrical action o...In this paper, a silicon-based neural probe with microfluidic channels was developed and evaluated. The probe can deliver chemicals or drugs to the target neurons while simultaneously recording the electrical action of these neurons extracellularly. The probe was fabricated by double-sided deep reactive ion etching （DRIE） from a silicon-on-insulator （SO1） wafer. The flu- idic channels were formed with V-shape groove etching on the silicon probe and sealed with silicon nitride and parylene-C. The shank of the probe is 4 mm long and 120 ~tm wide. The thickness of the probe is 100 ~tm. The probe has two fluidic chan- nels and two recording sites. The microfluidic channels can withstand a pressure drop as much as 30 kPa and the flow resisti ity of the microfluidic channel is 0.13 μL min-1 kPa-1, The typical impedance of the neural electrode is 32.3 kΩ at 1 kHz at room temperature.展开更多
基金supported by the National Key R&D Program of China under grant 2017YFB1002501the National Natural Science Foundation of China(No.61728402,No.31600781 and 31972929)+2 种基金Research Program of Shanghai Science and Technology Committee(17JC1402800,17JC1400202 and 19ZR1475000)Program of Shanghai Academic/Technology Research Leader(18XD1401900)Interdisciplinary Program of Shanghai Jiao Tong University(YG2016MS06).
文摘The delicate serpentine structures are widely used in high-performance stretchable electronics over the past decade.The metal interconnects encapsulated in biocompatible polymer Parylene-C film is a superior choice for long-term implantation in vivo,especially as neural interface to acquire electrophysiological signals or apply electrical stimulation.To avoid the physical contact damages from the neural tissues such as the brain or peripheral nerves,serpentine interconnects are utilized as stretchable electrodes and usually bonded to the soft elastomer substrate.The adhesion strength between the serpentine interconnects and the elastomer substrate becomes a considerable issue to ensure reliability and structural integrity.In this paper,the stretchable Parylene-C electrodes can be transfer printed onto arbitrary elastomer substrates by a thin layer of silicone rubber adhesive with low modulus for electrocorticogram(ECoG)recording.Mechanical simulation of serpentine structures consisting of same periodic arcs and different straight segments is investigated by uniaxial stretching.Then,the elastic stretchability of serpentine electrodes is further studied by simulation and experiments.After 5000 repetitive stretching cycles,the electrochemical impedance of microelectrodes remains in steady states.These results prove that the silicone rubber adhesive facilitates the interfacial bonding in the structure of stretchable electrodes as the compliant and reliable neural interface.
文摘Light management and electrical isolation are essential for the majority of optoelectronic nanowire （NW） devices. Here, we present a cost-effective technique, based on vapor-phase deposition of parylene-C and subsequent annealing, that provides conformal encapsulation, anti-reflective coating, improved optical properties, and electrical insulation for GaAs nanowires. The process presented allows facile encapsulation and insulation that is suitable for any nanowire structure. In particular, the parylene-C encapsulation functions as an efficient antireflection coating for the nanowires, with reflectivity down to 〈1% in the visible spectrum. Furthermore, the parylene-C coating increases photoluminescence intensity, suggesting improved light guiding to the NWs. Finally, based on this process, a NW LED was fabricated, which showed good diode performance and a clear electroluminescence signal. We believe the process can expand the fabrication possibilities and improve the devices. performance of optoelectronic nanowire
基金supported by the National Basic Research Program of China("973" Project) (Grant Nos. 2011CB933203, 2011CB933102)the National Natural Science Foundation of China (Grant Nos.31070965,90820002,60877035,60976026 and 61076023)
文摘In this paper, a silicon-based neural probe with microfluidic channels was developed and evaluated. The probe can deliver chemicals or drugs to the target neurons while simultaneously recording the electrical action of these neurons extracellularly. The probe was fabricated by double-sided deep reactive ion etching （DRIE） from a silicon-on-insulator （SO1） wafer. The flu- idic channels were formed with V-shape groove etching on the silicon probe and sealed with silicon nitride and parylene-C. The shank of the probe is 4 mm long and 120 ~tm wide. The thickness of the probe is 100 ~tm. The probe has two fluidic chan- nels and two recording sites. The microfluidic channels can withstand a pressure drop as much as 30 kPa and the flow resisti ity of the microfluidic channel is 0.13 μL min-1 kPa-1, The typical impedance of the neural electrode is 32.3 kΩ at 1 kHz at room temperature.
