Sensing Characteristic Enhancement of CMOS-Based ISFETs With Three-Dimensional Extended- Gate Architecture
IEEE Sensors Journal(2021)
Abstract
As the CMOS-based ion-sensitive field-effect transistor (ISFET) is scaling down to achieve a compact sensing array with high spatial resolution, reduction of sensing layer capacitance attenuates capacitive coupling efficiency of environmental input signals and decreases sensitivity performance. To address this issue, a concept of three-dimensional (3D) sensing structure is proposed and examined in this study. This can increase the sensing layer capacitance for a given footprint area. Based on our designs, a series of 3D sensing structures can be implemented with a standard CMOS foundry service and CMOS-compatible post processes. Our experimental results show that an 8.5
2
μm
2
footprint design of the 3D sensing structure can obtain approximately 2-fold increase in transconductance compared with a traditional ISFET with the same footprint. This enables pH sensitivity to be improved 1.5-fold in current response and 1.15-fold in voltage response. Therefore, the proposed 3D-structure ISFET can pave the way toward an ISFET sensing array with high sensitivity and high spatial resolution.
MoreTranslated text
Key words
Extended-gate,ISFET,sensing area,three-dimensional structure
AI Read Science
Must-Reading Tree
Example
![](https://originalfileserver.aminer.cn/sys/aminer/pubs/mrt_preview.jpeg)
Generate MRT to find the research sequence of this paper
Chat Paper
Summary is being generated by the instructions you defined