In a radio-frequency (r.f.) powered He glow-discharge plasma excitation source, sputtering of the sample atoms scarcely occurs when the bias current is not conducting. However, when the bias current is conducting, the sputtering rate of the sample increases rapidly with increasing the bias current. The maximum sputtering rate of the He excitation source reaches about 1/10 of the sputtering rate of the usual 13.56 MHz Ar glow-discharge plasma excitation source. The emission yield of the r.f. He glow-discharge plasma is found to be over 10-times larger than that of the usual 13.56 MHz Ar glow-discharge plasma. Although a bias current conducting method with an r.f. Ar glow-discharge excitation source becomes ineffective to enhance the excitation of atomic lines having an energy higher than 6.2 eV, the method with r.f. He glow-discharge excitation source is effective for the excitation of emission lines having a high excitation energy. The atomic emission lines of fluorine having an excitation energy larger than 14 eV can be observed with an r.f.-powered He glow-discharge plasma excitation source.
- Bias-current introduction
- Glow-discharge optical emission spectrometry
- Glow-discharge plasma
ASJC Scopus subject areas
- Analytical Chemistry