CMOS微环境pH传感芯片研究  

Research of CMOS Micro-Environment pH Sensor

作　　者：施朝霞[1] 朱大中[1] 

机构地区：[1]浙江大学信息与电子工程学系,微电子技术与系统设计研究所,杭州310027

出　　处：《传感技术学报》2006年第3期577-580,共4页Chinese Journal of Sensors and Actuators

基　　金：国家自然科学基金(NSFC)资助项目(60576050)

摘　　要：基于离子敏感场效应晶体管(ISFET)基本结构及其电学特性,提出了一种应用标准CMOS工艺实现的多层浮栅结构pH-ISFET。利用CMOS标准工艺中LPCVD淀积的Si3N4钝化层作为氢离子敏感层,pad工艺形成微区域独立传感窗口。片上集成100μm×100μm电极提供参考电位,消除了外加参考电位引起的溶液电压分布不均的现象。缓冲液从pH值1-13范围内对ISFET进行了测量,器件阈值电压随溶液pH值变化的平均灵敏度为44mV/pH,线性度在10%范围内。本结构可用于生物微环境pH值集成传感芯片设计中。Based on the Ion-Sensitive Field Effect Transistor structure and electro-characteristic, a pH-ISFET has a multi-layer floating electrode structure realized in standard CMOS technology is presented. The pH-ISFET uses silicon nitride passivation layer deposited through LPCVD as a pH sensitive material. The pad process forms independent sensing area in micro-size. An on-chip integrated 100μm by 100μm electrode offers reference voltage, which can eliminate asymmetric voltage distribution induced by external voltage. The ISFET sensor has an average sensitivity of 44 mV/pH between pH 1 and pH 13, its linearity is in the range of 10 percent. This structure can be used to design integrated pH sensor on chip, suited for making biological microenvironment measurement.

关 键 词：离子敏场效应晶体管 CMOS工艺 多层浮栅 集成参考电极 

分 类 号：TN432[电子电信—微电子学与固体电子学]