Bombardment energies of O2+ in low pressure reactive ion etching

Abstract

Quadrupole mass spectroscopy has been used to resolve the energy distributions of O2+ on the substrate plane of a parallel plate reactive ion etching reactor. Energy spectra show pronounced structures caused by charge exchange collisions in the plasma sheath in combination with rf modulation. Additionally, continuous distributions are found which are attributed to the effect of elastic scattering of ions.

Studies of Ion Kinetic-Energy Distributions in the Gaseous Electronics Conference Rf Reference Cell

“…Subsequently, the measurement of ion kinetic-energy distributions (IEDs) in low pressure, rf discharges generated in parallel-plate reactors has been used to investigate: (1) ion bombardment of the grounded electrode in argon plasmas [5–10]; (2) the role of ions in discharges sustained in etching gases [11–13]; (3) the angular distribution of ions striking the electrodes [14,15]; and (4) the effect of symmetric charge-transfer collisions on the shapes of IEDs [16]. Additional experiments have been performed to measure the energies of ions striking the surface of the powered electrode in capacitively coupled rf discharges [13,15, 17–19].…”

“…Additional experiments have been performed to measure the energies of ions striking the surface of the powered electrode in capacitively coupled rf discharges [13,15, 17–19]. …”

Compact floating ion energy analyzer for measuring energy distributions of ions bombarding radio-frequency biased electrode surfaces

“…3,4,7 Several other authors have presented measurements using differentially pumped ion energy analyzers in conjunction with quadrapole mass spectrometers. 12,13,17,18,22,24 The use of differential pumping for ion energy measurements can be problematic because of the spatial requirements of the additional equipment, which are often incompatible with preexisting plasma reactor components, particularly those used in industry. Ingram and Braithwaite designed and built a compact ion energy analyzer that did not require differential pumping and were able to measure ion energy distributions in a capacitively coupled plasma reactor.…”

“…6 The measurements of Janes and Huth were also at the powered electrode. 12,13 The analyzer described in this article was used to measure the ion energy distributions at the rf-biased electrostatic chuck of a Lam TCP reactor in Ar, Ne, Ar/Ne, O 2 , and O 2 /CF 4 discharges over a wide range of plasma operating parameters. The design requires no differential pumping and the electronics are capable of operating while floating on several hundreds of volts of rf bias.…”

Retarded Field Energy Analyzer as a tool to Study the Ion Velocity Distribution Functions on Radio Frequency Argon Plasma in Expanding Magnetic Field at Low Pressures

“…Besides this, retarding field energy analyzers (RFEAs) have been used extensively for determining the IED in plasma discharges in recent decades Coburn et al 1972, Kuypers et al 1988,Ingram et al 1990, Janes et al 1992, Charles et al 1992and 1993. The potential of a grid placed in front of a beam of ions is increased until the beam is stopped.…”