A Highly Sensitive FET-Type Humidity Sensor with Inkjet-Printed Pt-In2O3 Nanoparticles at Room Temperature

Nanoscale Research Letters

Jong-Ho Lee¹  Zhanyu Wu²  Meile Wu³  Xiaoshi Jin³ 

[1] Department of Electrical and Computer Engineering and Inter-University Semiconductor Research Center, Seoul National University, 151-742, Seoul, Republic of Korea;Huafu High Technology Energy Storage Co., Ltd, 225600, Yangzhou, Jiangsu, China;Huafu (JiangSu) Lithium Battery High Technology Co., Ltd, 225600, Yangzhou, Jiangsu, China;School of Information Science and Engineering, Shenyang University of Technology, 110870, Shenyang, China;

关键词: Pt-InO;    Inkjet printing;    Humidity sensor;    FET sensor;    Work function;   

DOI  :  10.1186/s11671-020-03426-6

来源: Springer

【 摘 要 】

In this work, Pt-doped In2O3 nanoparticles (Pt-In2O3) were inkjet printed on a FET-type sensor platform that has a floating gate horizontally aligned with a control gate for humidity detection at room temperature. The relative humidity (RH)-sensing behavior of the FET-type sensor was investigated in a range from 3.3 (dry air in the work) to about 18%. A pulsed measurement method was applied to the transient RH-sensing tests of the FET-type sensor to suppress sensor baseline drift. An inkjet-printed Pt-In2O3 resistive-type sensor was also fabricated on the same wafer for comparison, and it showed no response to low RH levels (below 18%). In contrast, the FET-type sensor presented excellent low humidity sensitivity and fast response (32% of response and 58 s of response time for 18% RH) as it is able to detect the work-function changes of the sensing material induced by the physisorption of water molecules. The sensing mechanism of the FET-type sensor and the principle behind the difference in sensing performance between two types of sensors were explained through the analysis on the adsorption processes of water molecules and energy band diagrams. This research is very useful for the in-depth study of the humidity-sensing behaviors of Pt-In2O3, and the proposed FET-type humidity sensor could be a potential candidate in the field of real-time gas detection.

【 授权许可】

CC BY