An ultralow power nanosensor array for selective detection of air pollutants. (10th October 2019)

• Record Type: Journal Article
• Authors: Prajapati, Chandra Shekhar; Benedict, Samatha; Bhat, Navakanta
• Is Part Of: Nanotechnology. Volume 31:Number 2(2020)
• Publication Date: 2019-10-10
• Subjects: nanosensor -- ultralow power -- nanogap -- sensor array -- selectivity; Nanotechnology -- Periodicals; Nanotechnology -- Periodicals; Nanotechnology; Publications périodiques; Nanotechnologies; Periodicals; 620.5
• DOI: 10.1088/1361-6528/ab44fd
• Languages: English
• ISSNs: 0957-4484

Abstract

Abstract: Semiconducting metal oxide gas sensors typically operate at a high temperature and consume hundreds of milliwatts of power. Therefore there is great demand for the development of a low-power gas-sensing technology that can sensitively and selectively detect the gas analytes present in the atmosphere. We report an ultralow-power nanosensor array platform, integrated with an independently controlled nanoheater of size 4 μ m × 100 nm, which consumes ∼1.8 mW power when operated continuously at 300 °C. The heaters exhibit a fast thermal response time of less than 1 μ s, and can be utilized to operate in duty cycle mode, leading to power saving. The active area of the nanosensor is 1 μ m × 200 nm, defined by sensing electrodes with a nanogap of ∼200nm, leading to small form factor. As a proof of concept, each of the sensing elements in the array is functionalized with different sensing materials to demonstrate a low-power, sensitive and selective multiplexed gas-sensing technology for the simultaneous detection of CO (∼93.2% for 3 ppm at 300 °C), CO2 (∼76.3% for 1000 ppm at 265 °C), NO2 (∼2301% for 3 ppm at 150 °C) and SO2 (∼94% for 3 ppm at 265 °C). The technology described here uses scalable crossbar architecture for sensor elements, thus enabling the integration of additional sensing materials and making it customizable for specific applications.