隨著科技的發展進步，人類的生活品質也隨著之愈加便利。然而，科技的進步帶來了許多好處，但也付出了環境污染的代價，其中影響範圍最廣的為空氣污染莫屬。為了解決此問題，氣體感測技術不斷的發展，現今氣體檢測的方法有很多種，其中光學式氣體感測器設備龐大且十分昂貴，致使難以達到大量場域的廣設。

本研究利用光譜晶片開發了微型氣體量測系統並且進行氣體感測實驗，其原理是利用光在薄膜表面發生干涉，再由微型光譜儀取得光譜訊號。在進行氣體感測驗證實驗時，開發了四種不同材料的薄膜，包括量子點、氧化鋅、二氧化鈦和三氧化鎢。利用儀器科學中心的氣體檢測平台對這四種薄膜進行氣體感測驗證，其中為了方便控制系統且分析光譜儀的訊號，同時也開發了即時追蹤干涉光譜位移的系統，以便能有效率地取得實驗數據。

本研究測量了薄膜在密封腔體中通入氣體後的干涉光譜。量測中發現量子點薄膜對溫度及濕度變化而造成光譜移動的反應，其中水氣的吸附導致干涉光譜的峰值向更長的波長方向移動。本研究根據結果建立了溫度和濕度的檢量線，結果顯示量子點的波峰波長移動與相對濕度有很強的相關性(R2 > 0.95)，此發現證實了目前光學系統可以正常運作。

With the advancement of technology, the quality of human life has significantly improved, providing increased convenience. However, this progress has cause environmental pollution, with air pollution being the most pervasive and widespread issue. To address this problem, gas sensing technology has been continuously evolving. Currently, there are various methods for gas detection, but optical gas sensors are often large and expensive, making it challenging to deploy them extensively in different field settings.

In this study, a micro gas measurement system was developed using Spectro-chip, enabling gas sensing experiments. The principle relied on the interference of light on the surface of thin films, with the spectral signals obtained using a micro spectrometer. During the gas sensing validation experiments, four different thin film materials were developed, including quantum dots, zinc oxide, titanium dioxide, and tungsten trioxide. These films were subjected to gas sensing validation using the gas detection platform at the Taiwan Instrument Research Institute. To facilitate system control and analyze the spectrometer’s signals, a realtime tracking system for interference spectrum displacement was also developed, allowing for efficient acquisition of experimental data.

The measurement involved capturing the interference spectrum of the thin films when
gases were introduced into a sealed chamber. It was observed that the quantum dot film exhibited spectral shifts in response to changes in temperature and humidity, with water vapor adsorption causing the peak of the interference spectrum to shift towards longer wavelengths. The analysis revealed a strong correlation (R2 > 0.95) between the wavelength shift of the quantum dot peak and the relative humidity. This finding confirms the proper functioning of the current optical system.

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