Multifunctional Complementary Metal–Oxide–Semiconductor (CMOS) Compatible 2D Layered Film-Based Gas Sensing Circuits by Floating-Gate Coupling Effect for Sub-ppm Detection Limit

Che-Hao Hsu^1*, Ling Lee(¹, Yu-Lun Chueh¹

¹Material Science and Engineering, National Tsing Hua University, Hsinchu City, Taiwan

* Presenter:Che-Hao Hsu, email:amoschhs105ren@gmail.com

A 2D SnSe2 layered film-based gas detector incorporating a floating-gate device coupled with metal interconnect wiring structures was proposed and demonstrated for the first time. Linear amplification can be readily implemented using a coupling ratio design, which refers to the capacitance ratio between gate and device in the sense amplifier circuits. A sensitivity of 102 mV/ppm can be obtained using the 2D SnSe2 layered film with a thickness of 10 nm. The 2D SnSe2 layered film-based complementary metal–oxide–semiconductor (CMOS) gas detector features highly sensitive, wide, and adjustable dynamic ranges with a real-time response of the sub-ppm detection limit on NO2 gas. In addition, the synthesis process of the SnSe2 layered film can occur at a low temperature and can be operated at room temperature. Furthermore, 3×3 gas detector arrays with peripheral circuits demonstrate the functionality of multiple gas detection simultaneously and 16×16 arrays with a decoder and other peripheral circuits were constructed and simulated, providing the spatial distribution of the gas concentration in a specific region. The performance of the proposed detector is comparable to that of the other state-of-the-art gas sensors.

Keywords: NO2 gas sensor, floating-gate field-effect transistor, adjustable dynamic range