A floating hairpin resonator probe is used to measure electron density within the radiofrequency cycle of a parallel plate capacitively coupled plasma at steady state. A time resolution capable of detecting electron density oscillations within the radiofrequency cycle is demonstrated. Electron density oscillations are observed at the drive frequency over a range of operating conditions including 10–250 mTorr (1.3–33 Pa) in argon driven at 13.56 or 27.12 MHz. Localized electron density oscillation amplitudes show moderate agreement with literature and fluid simulations near the powered electrode and disagreement in the plasma bulk. The technique is useful for studying electron heating mechanisms in radiofrequency discharges due to its high time resolution.

中文翻译：

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发夹谐振器探针用于射频相位分辨电子密度测量

浮动发夹谐振器探针用于在稳定状态下测量平行板电容耦合等离子体的射频周期内的电子密度。演示了一种能够检测射频周期内电子密度振荡的时间分辨率。在一系列工作条件下，包括13–56或27.12 MHz的氩气中的10–250 mTorr（1.3–33 Pa）的工作条件下，在驱动频率下观察到电子密度振荡。局部电子密度振荡幅度与动力电极附近的文献和流体模拟显示适度的一致性，并且在等离子体体积中存在分歧。由于其高时间分辨率，该技术可用于研究射频放电中的电子加热机理。