Ion energy distribution measurements in rf and pulsed dc plasma discharges

Abstract

A commercial retarding field analyzer is used to measure the time-averaged ion energy distributions of impacting ions at the powered electrode in a 13.56 MHz driven, capacitively coupled, parallel plate discharge operated at low pressure. The study is carried out in argon discharges at 10 mTorr where the sheaths are assumed to be collisionless. The analyzer is mounted flush with the powered electrode surface where the impacting ion and electron energy distributions are measured for a range of discharge powers. A circuit model of the discharge, in combination with analytical solutions for the ion energy distribution in radio-frequency sheaths, is used to calculate other important plasma parameters from the measured energy distributions. Radio-frequency compensated Langmuir probe measurements provide a comparison with the retarding field analyzer data. The time-resolved capability of the retarding field analyzer is also demonstrated in a separate pulsed dc magnetron reactor. The analyzer is mounted on the floating substrate holder and ion energy distributions of the impinging ions on a growing film, with 100 ns time resolution, are measured through a pulse period of applied magnetron power, which are crucial for the control of the microstructure and properties of the deposited films.

RFEA Measurements of High-Energy Electrons in a Helicon Plasma Device with Expanding Magnetic Field

“…D is the discriminator grid and was scanned from 0 to −120 V, R is the repeller grid biased at +100 V and C is the collector kept at +9 V. The innermost grid was not needed in this configuration and was therefore grounded. This grid configuration with the discriminator in front of the repeller is similar to the one used by Gahan et al [24,30]. Only the electrons with energies high enough to overcome the sheath potential in front of the probe will be recorded, so that the RFEA detects only the high-energy tail of the EEDF [30].…”

“…This grid configuration with the discriminator in front of the repeller is similar to the one used by Gahan et al [24,30]. Only the electrons with energies high enough to overcome the sheath potential in front of the probe will be recorded, so that the RFEA detects only the high-energy tail of the EEDF [30]. The high-energy electron-tail temperature can be extracted from a linear fit to a plot of the logarithm of collector current [31]:…”

A novel source of atomic hydrogen for passivation of defects in silicon

“…In comparison leaves in this work were exposed to ions with lower energies of up to several hundred eV [22,23]. However the exposure to energetic ions and UV radiation may act to increase the energy of the hydrogen plasma within the leaf [22,24].…”

Development of double-pulse lasers ablation system for generating gold ion source under applying an electric field

“…The electric circuit was described in previous work [35,36]. The capacitor bank (10 nF) was charged by a dc power supply (high voltage 1200 V, max.…”