光學式二氧化氮氣體感測系統

The Optical Gas Detection System for Nitrogen Dioxide

鄭杰晰(Jie-Si Jheng) ； 王俊凱(Chun-Kai Wang) ； 邱裕中(Yu-Zung Chiou)

《科儀新知》 230期 (2022/03) Pp. 56-69

摘要

基於因應在NO_2氣體感測之「廣布建置」與「簡單維護」之需求上，本團隊開發光學式NO_2氣體感測系統，感測晶片從磊晶結構設計、磊晶成長、晶粒製作、晶粒封裝、光路系統開發整合到最後實測與修正皆為國產製造，成本較傳統高階儀器便宜許多，並且在感測元件上已進入小量產階段。感測晶片透過磊晶結構的光學設計，特別針對NO_2氣體光吸收頻譜進行設計，因此該晶片只會對特定區域範圍之光能量進行反應，並產生相應電流值，如此可以排除環境其他光線之影響。系統預設置於嚴苛環境，因此在設計上採高規格，通過IPX3防水認證，並於環保署台南測站上方裸落環境中連續測試長達2年。在特色上具有不需耗材、容易維護、瞬間反應、解析度達2 ppb等特點，在與環保署台南測站數據比較，決定係數高達0.786。

並列摘要

Our team develops an optical NO_2 gas sensing system based on the demand of ＂wide deployment＂ and ＂simple maintenance＂ in NO_2 gas sensors. The gas sensors are made in our country from structure design, epitaxial growth, chip fabrication, chip packaging, optical path development, and system integration. The cost of our development system is much cheaper than traditional precision instruments, and the gas sensing chips have entered the stage of pilot run. These sensing chips are designed with an epitaxial structure, especially for the light absorption spectrum of NO_2 gas. Therefore, the chips can only detect light wavelengths in a specific range and generate corresponding photocurrents, which can exclude the influence of ambient light. Our system is placed in a harsh environment, so it is designed with high specifications and has passed the IPX3 waterproof certification. And our system has been continuously tested at the Tainan station of the Environmental Protection Agency for two years. It has the characteristics of no consumables, easy maintenance, instant response, and a resolution of 2 ppb. Compared with the data from the Tainan station of the Environmental Protection Agency, the coefficient of determination is as high as 0.786.