Development of Laser-Induced Fluorescence Spectroscopy for the Measurement of Dynamic Bahaviors of Ion Flow from Plasmas

2022 Fiscal Year Final Research Report

• Project/Area Number: 19H01886
• Research Category: Grant-in-Aid for Scientific Research (B)
• Allocation Type: Single-year Grants
• Section: 一般
• Review Section: Basic Section 14030:Applied plasma science-related
• Research Institution: Kyoto University
• Principal Investigator: Urabe Keiichiro 京都大学, 工学研究科, 助教 (80725250)
• Project Period (FY): 2019-04-01 – 2023-03-31
• Keywords: プラズマ / イオン / レーザー分光 / 時空間速度分布 / イオンシース

Outline of Final Research Achievements

The purpose of this study is to develop advanced measurement system of ion dynamics in plasmas, based on the laser-induced fluorescence spectroscopy method. In the first half of the research period, we constructed a spectroscopic system using a continuous diode laser as a light source and succeeded in capturing ion motion along magnetic fields and ion density fluctuations caused by impurity molecules in low-pressure plasma sources. In the latter half of the research period, we also measured ion acceleration features in the pre-sheath/ion sheath regions formed in front of the metal electrode and demonstrated time-resolved measurements of ion energy distribution following an AC bias voltage on the order of kHz.

Free Research Field

プラズマ分光学

Academic Significance and Societal Importance of the Research Achievements

本研究は，従来のレーザー誘起蛍光法にはない【ハイスループット計測】という考え方を新たに導入したものであり，（１）プラズマ（イオン）挙動の連続的な計測や，（２）高速なシース（イオン）変動現象を捉えることに成功した．これらの研究成果は，イオン挙動やその制御性が性能に決定的な影響を与える宇宙電気推進器や材料プロセス用プラズマ（イオン）源の研究開発やオペレーションに活用されるものと期待される．また，その場で計測結果を出力する本研究の提案手法はビッグデータ・AI処理に最適化可能であり，分光計測が活用される様々な工学分野（例えば，燃焼プロセス診断，天文観測）への波及が期待される．