Detection of free-radical in plasmas by terahertz frequency-domain spectroscopy

本研究的目的是通过建立在太赫兹区对等离子体中产生的少量不稳定分子进行腔体衰荡检测的测量方法，对等离子体-基元反应进行现场分析。在实验中，由于所构建的测量系统在机械和时间上都不具有足够的稳定性，无法利用频域观测数据中包含的大误差信号来进行稳定测量。

The aim of this research is to do the in-situ analysis of the plasma-elementary reaction by establishing the method of measurement using Cavity Ring-Down detection at the terahertz region for the small-quantity unstable-molecules that is generated in the plasmas.In the experiment, the stable measurement could not be performed by the large error signal contained in the observed data of the frequency domain because the constructed measuring system did not have enough stability in mechanically and temporally.As the result, it becomes clear that there need more stable spectrometer and the plasma chamber with the thermal stability.