摘要
In this paper,a polyimide-based flexible device that integrates 16 micro-LEDs and 16 IrO_(x)-modified microelectrodes for synchronous photostimulation and neural signal recording is presented.The 4×4 micro-LEDs(dimensions of 220×270×50μm^(3),700μm pitch)are fixed in the SU-8 fence structure on a polyimide substrate and connected to the leads via a wire-bonding method.The recording electrodes share a similar fabrication process on the polyimide with 16 microelectrode sites(200μm in diameter and 700μm in pitch)modified by iridium oxide(IrO_(x)).These two subparts can be aligned with alignment holes and glued back-to-back by epoxy,which ensures that the light from the LEDs passes through the corresponding holes that are evenly distributed around the recording sites.The long-term electrical and optical stabilities of the device are verified using a soaking test for 3 months,and the thermal property is specifically studied with different duty cycles,voltages,and frequencies.Additionally,the electrochemical results prove the reliability of the IrO_(x)-modified microelectrodes after repeated pressing or friction.To evaluate the tradeoff between flexibility and strength,two microelectrode arrays with thicknesses of 5 and 10μm are evaluated through simulation and experiment.The proposed device can be a useful mapping optogenetics tool for neuroscience studies in small(rats and mice)and large animal subjects and ultimately in nonhuman primates.
基金
This work was partially funded by the National Key R&D Program of China under grant 2017YFB1002501
the National Natural Science Foundation of China(No.51475307 and 61728402)
the Research Program of Shanghai Science and Technology Committee(17JC1402800 and 15JC1400103)
the Program of Shanghai Academic/Technology Research Leader(18XD1401900)
ZBYY-MOE Joint Funding(6141A02022604)
the China Scholarship Council(201606230100).
