Measurements of radical densities in radio-frequency fluorocarbon plasmas using infrared absorption spectroscopy

M. Haverlag, E. Stoffels, W.W. Stoffels, G.M.W. Kroesen, F.J. de Hoog

Research output: Contribution to journalArticleAcademicpeer-review

70 Citations (Scopus)

Abstract

Densities of CF 2 radicals, rotational temperatures, and the degree of dissociation in radio-frequency fluorocarbon plasmas have been measured using Fourier transform infrared absorption spectroscopy and tunable diode laser infrared absorption spectroscopy. The CF2 densities obtained in CF4, CHF3fC2F6, and CF2C12 plasmas indicate that the partial pressure of CF2 is around l%-5% of the total pressure. From the spatial dependence of the CF2 density it was established that at high pressure, CF2 is produced either on the rf electrode or close to the rf electrode. Furthermore, a comparison between measured absorption spectra and a simulation of the rotational distributions has revealed that the rotational temperatures of CF4, CF2, and HF are all close to room temperature. FTIR spectra indicate that in plasmas of gases with a low F/C ratio (due to the presence of H or Cl) the source gas is converted for a significant part into other species.

Original languageEnglish
Pages (from-to)3102-3108
Number of pages7
JournalJournal of Vacuum Science and Technology A: Vacuum, Surfaces, and Films
Volume12
Issue number6
DOIs
Publication statusPublished - 1 Jan 1994

Fingerprint

Fluorocarbons
fluorocarbons
Infrared absorption
Absorption spectroscopy
infrared absorption
Infrared spectroscopy
radio frequencies
absorption spectroscopy
infrared spectroscopy
Plasmas
Plasma Gases
Electrodes
electrodes
Gases
gases
Partial pressure
Temperature
partial pressure
Semiconductor lasers
Absorption spectra

Cite this

@article{cd40538cbe9746e59fb3a83ccd369a04,
title = "Measurements of radical densities in radio-frequency fluorocarbon plasmas using infrared absorption spectroscopy",
abstract = "Densities of CF 2 radicals, rotational temperatures, and the degree of dissociation in radio-frequency fluorocarbon plasmas have been measured using Fourier transform infrared absorption spectroscopy and tunable diode laser infrared absorption spectroscopy. The CF2 densities obtained in CF4, CHF3fC2F6, and CF2C12 plasmas indicate that the partial pressure of CF2 is around l{\%}-5{\%} of the total pressure. From the spatial dependence of the CF2 density it was established that at high pressure, CF2 is produced either on the rf electrode or close to the rf electrode. Furthermore, a comparison between measured absorption spectra and a simulation of the rotational distributions has revealed that the rotational temperatures of CF4, CF2, and HF are all close to room temperature. FTIR spectra indicate that in plasmas of gases with a low F/C ratio (due to the presence of H or Cl) the source gas is converted for a significant part into other species.",
author = "M. Haverlag and E. Stoffels and W.W. Stoffels and G.M.W. Kroesen and {de Hoog}, F.J.",
year = "1994",
month = "1",
day = "1",
doi = "10.1116/1.578943",
language = "English",
volume = "12",
pages = "3102--3108",
journal = "Journal of Vacuum Science and Technology A: Vacuum, Surfaces, and Films",
issn = "0734-2101",
publisher = "AVS Science and Technology Society",
number = "6",

}

Measurements of radical densities in radio-frequency fluorocarbon plasmas using infrared absorption spectroscopy. / Haverlag, M.; Stoffels, E.; Stoffels, W.W.; Kroesen, G.M.W.; de Hoog, F.J.

In: Journal of Vacuum Science and Technology A: Vacuum, Surfaces, and Films, Vol. 12, No. 6, 01.01.1994, p. 3102-3108.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Measurements of radical densities in radio-frequency fluorocarbon plasmas using infrared absorption spectroscopy

AU - Haverlag, M.

AU - Stoffels, E.

AU - Stoffels, W.W.

AU - Kroesen, G.M.W.

AU - de Hoog, F.J.

PY - 1994/1/1

Y1 - 1994/1/1

N2 - Densities of CF 2 radicals, rotational temperatures, and the degree of dissociation in radio-frequency fluorocarbon plasmas have been measured using Fourier transform infrared absorption spectroscopy and tunable diode laser infrared absorption spectroscopy. The CF2 densities obtained in CF4, CHF3fC2F6, and CF2C12 plasmas indicate that the partial pressure of CF2 is around l%-5% of the total pressure. From the spatial dependence of the CF2 density it was established that at high pressure, CF2 is produced either on the rf electrode or close to the rf electrode. Furthermore, a comparison between measured absorption spectra and a simulation of the rotational distributions has revealed that the rotational temperatures of CF4, CF2, and HF are all close to room temperature. FTIR spectra indicate that in plasmas of gases with a low F/C ratio (due to the presence of H or Cl) the source gas is converted for a significant part into other species.

AB - Densities of CF 2 radicals, rotational temperatures, and the degree of dissociation in radio-frequency fluorocarbon plasmas have been measured using Fourier transform infrared absorption spectroscopy and tunable diode laser infrared absorption spectroscopy. The CF2 densities obtained in CF4, CHF3fC2F6, and CF2C12 plasmas indicate that the partial pressure of CF2 is around l%-5% of the total pressure. From the spatial dependence of the CF2 density it was established that at high pressure, CF2 is produced either on the rf electrode or close to the rf electrode. Furthermore, a comparison between measured absorption spectra and a simulation of the rotational distributions has revealed that the rotational temperatures of CF4, CF2, and HF are all close to room temperature. FTIR spectra indicate that in plasmas of gases with a low F/C ratio (due to the presence of H or Cl) the source gas is converted for a significant part into other species.

UR - http://www.scopus.com/inward/record.url?scp=21844510712&partnerID=8YFLogxK

U2 - 10.1116/1.578943

DO - 10.1116/1.578943

M3 - Article

AN - SCOPUS:21844510712

VL - 12

SP - 3102

EP - 3108

JO - Journal of Vacuum Science and Technology A: Vacuum, Surfaces, and Films

JF - Journal of Vacuum Science and Technology A: Vacuum, Surfaces, and Films

SN - 0734-2101

IS - 6

ER -