Improved Double-Probe Technique for Spatially Resolved Diagnosis of Dual-Frequency Capacitive Plasmas

• Published in: Plasma science & technology Vol. 15; no. 6; pp. 511 - 515
• Main Author: 陆文琪 蒋相站 刘永新 杨烁 张权治 李小松 徐勇 朱爱民 王友年
• Format: Journal Article
• Language: English
• Published: 01.06.2013
• Subjects: Density; Discharge; Electron temperature; Emission; High frequencies; Plasmas; Radial distribution; Simulation; 双探头; 双频; 无线电频率; 电容耦合; 离子密度; 空间分辨; 等离子体; 诊断技术
• ISSN: 1009-0630
• DOI: 10.1088/1009-0630/15/6/05

The conventional double-probe technique was improved with a combination of selfpowering and radio-frequency（RF） choking.RF perturbations in dual-frequency capacitively coupled discharge were effectively eliminated,as judged by the disappearance of self-bias on the probes.The improved technique was tested by spatially resolved measurements of the electron temperature and ion density in both the axial and radial directions of a dual-frequency capacitive plasma.The measured data in the axial direction were compared with simulation results,and they were excellently consistent with each other.The measured radial distributions of the ion density and electron temperature were influenced significantly by the lower frequency（LF） power.It was shown that superposition of the lower frequency to the higher frequency（HF） power shifted the maximum ion density from the radial center to the edge region,while the trend for the electron temperature profile was the opposite.The changing feature of the ion density distribution is qualitatively consistent with that of the optical emission intensity reported.