title: Fabrication and Evaluation of a Graphene Oxide-Based Capacitive Humidity Sensor.
abstract: In this study, a CMOS compatible capacitive humidity sensor structure was designed and fabricated on a 200 mm CMOS BEOL Line. A top Al interconnect layer was used as an electrode with a comb/serpent structure, and graphene oxide (GO) was used as sensing material. XRD analysis was done which shows that GO sensing material has a strong and sharp (002) peak at about 10.278°, whereas graphite has (002) peak at about 26°. Device level CV and IV curves were measured in mini-environments at different relative humidity (RH) level, and saturated salt solutions were used to build these mini-environments. To evaluate the potential value of GO material in humidity sensor applications, a prototype humidity sensor was designed and fabricated by integrating the sensor with a dedicated readout ASIC and display/calibration module. Measurements in different mini-environments show that the GO-based humidity sensor has higher sensitivity, faster recovery time and good linearity performance. Compared with a standard humidity sensor, the measured RH data of our prototype humidity sensor can match well that of the standard product.
authors.affiliation: School of Mechanical Engineering, Shanghai Jiao Tong University, Shanghai 200240, China. fengjf@sjtu.edu.cn.
authors.forename: Jinfeng
authors.initials: J
authors.lastname: Feng
authors.affiliation: Process Technology Department, Shanghai IC R&amp;D Center, Shanghai 201210, China. kangxiaoxv@icrd.com.cn.
authors.forename: Xiaoxu
authors.initials: X
authors.lastname: Kang
authors.affiliation: Process Technology Department, Shanghai IC R&amp;D Center, Shanghai 201210, China. zuoqingy@icrd.com.cn.
authors.forename: Qingyun
authors.initials: Q
authors.lastname: Zuo
authors.affiliation: Process Technology Department, Shanghai IC R&amp;D Center, Shanghai 201210, China. yuanchao@icrd.com.cn.
authors.forename: Chao
authors.initials: C
authors.lastname: Yuan
authors.affiliation: Process Technology Department, Shanghai IC R&amp;D Center, Shanghai 201210, China. wangweijun@icrd.com.cn.
authors.forename: Weijun
authors.initials: W
authors.lastname: Wang
authors.affiliation: Process Technology Department, Shanghai IC R&amp;D Center, Shanghai 201210, China. yhzhao@icrd.com.cn.
authors.forename: Yuhang
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: PIE Department III, Shanghai Huahong Grace Semiconductor Manufacturing Corporation, Shanghai 201206, China. limin.zhu@hhgrace.com.
authors.forename: Limin
authors.initials: L
authors.lastname: Zhu
authors.affiliation: PIE Department III, Shanghai Huahong Grace Semiconductor Manufacturing Corporation, Shanghai 201206, China. hanwei.lu@hhgrace.com.
authors.forename: Hanwei
authors.initials: H
authors.lastname: Lu
authors.affiliation: PIE Department III, Shanghai Huahong Grace Semiconductor Manufacturing Corporation, Shanghai 201206, China. juying.chen@hhgrace.com.
authors.forename: Juying
authors.initials: J
authors.lastname: Chen
keywords: capacitive sensing; graphene oxide; humidity sensor; relative humidity