阵列式CMOS细胞电信号传感芯片

介绍了一种采用0.6μm标准CMOS工艺实现的阵列式细胞电生理信号传感芯片。该芯片集成了6×6单元有源传感阵列、模拟多路选择器、输出缓冲器、参考源和数字控制电路,实现了传感电路和后端信号处理电路的单片化集成。传感单元面积为60μm×60μm,包含15μm×15μm的传感电极和有源预处理电路,线性放大幅值范围100μV～25mV的微小信号,电压增益为40dB。同时单元电路采用相关二次采样工作模式,采样信号可经后续差分电路除去固定模式噪声,提高传感器的精度。在标准CMOS工艺基础上,应用lift-off工艺对电极进行后续加工,提高其生物测量适应性。并通过封装技术的改进,使芯片适合在电解液环境下工作。在溶液中的模拟生物电学测试验证了芯片的功能。

CMOS Biosensor Array for Recording in Vitro Electrophysiological Activities of Cells

A new biosensor array for recording in vitro electrophysiological activities of cells is reported. It is fabricated in a 0.6 μm standard CMOS process, consisting of 6×6 active sensor array, analog multiplexer, output buffers, reference sources and digital controlling circuits. Each sensor cell covers a surface area of 60 μm×60 μm, including a 15 μm×15 μm electrode and pre-processing circuit which ia able to linearly amplify signals with amplitudes from 100 μV to 25 mV, and the voltage gain is 40 dB. Correlated double sampled-and-hold(CDS) working mode is applied in pre-processing circuit to improve the precision of the biosensor by eliminating the fixed pattern noise(FPN) of the circuit. Following the standard CMOS process, extended process of electrodes and improved package technique are implemented to adapt the chip to biocompatibility as well as electrolyte environment. Results from the simulated testing in solution prove the function of the biosensor chip.