Parylene C-Based Flexible Electronics for pH Monitoring Applications

Sensors

Tatiana Trantidou²  Mehvesh Tariq²  Cesare M. Terracciano¹  Christofer Toumazou² 

[1] National Heart and Lung Institute, Imperial College London, London W12 0NN, UK; E-Mail:;Centre for Bio-Inspired Technology, Department of Electrical and Electronic Engineering, Imperial College London, London SW7 2AZ, UK; E-Mails:

关键词: Parylene C;    flexible electronics;    pH sensor;    extended gate;    discrete MOSFETs;   

DOI  :  10.3390/s140711629

来源: mdpi

【 摘 要 】

Emerging materials in the field of implantable sensors should meet the needs for biocompatibility; transparency; flexibility and integrability. In this work; we present an integrated approach for implementing flexible bio-sensors based on thin Parylene C films that serve both as flexible support substrates and as active H⁺ sensing membranes within the same platform. Using standard micro-fabrication techniques; a miniaturized 40-electrode array was implemented on a 5 μm-thick Parylene C film. A thin capping film (1 μm) of Parylene on top of the array was plasma oxidized and served as the pH sensing membrane. The sensor was evaluated with the use of extended gate discrete MOSFETs to separate the chemistry from the electronics and prolong the lifetime of the sensor. The chemical sensing array spatially maps the local pH levels; providing a reliable and rapid-response (<5 s) system with a sensitivity of 23 mV/pH. Moreover; it preserves excellent encapsulation integrity and low chemical drifts (0.26–0.38 mV/min). The proposed approach is able to deliver hybrid flexible sensing platforms that will facilitate concurrent electrical and chemical recordings; with application in real-time physiological recordings of organs and tissues.

【 授权许可】

CC BY   
© 2014 by the authors; licensee MDPI, Basel, Switzerland.