Diagnostical measurements in a single electrode, atmospheric pressure, microwave plasma

Kirsch, B.; Hanamura, S.; Wineforder, J.D.

doi:10.1016/0584-8547(84)80115-9

Cited by 25 publications

(4 citation statements)

References 13 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…A crucial factor limiting both the power of detection and analytical accuracy was the difficulty of introducing a sample in the form of an aerosol or a cold gas flow centrally into the plasma, because the central zones are the hottest. This is clearly shown both by gas temperatures and excitation temperatures as reported by Kirch et al [3], and by the radially resolved measurements acquired by Bings et al [4]. Efforts have been made to improve the introduction of aerosols into the CMP by use of mantle gases, enabling wall stabilization of the plasma, and by introducing the sample aerosols through parallel cylindrical channels in the axial direction near to the electrode tip.…”

Section: Microwave Plasmasmentioning

confidence: 76%

The development of microplasmas for spectrochemical analysis

Broekaert

2002

Anal Bioanal Chem

View full text Add to dashboard Cite

Miniaturized microwave, high-frequency, and dc-powered microplasmas are discussed, with emphasis on the state-of-the-art and development trends. Specific atomic emission sources discussed include the microstrip microwave plasma operated in argon and helium at ca 10-30 W and below 1 L min(-1) gas at atmospheric pressure, the capacitively coupled microplasma, operated at 13.56 MHz, 5-25 W, and 17-150 mL min(-1) helium, the miniaturized inductively coupled plasma operated at several watts and reduced pressure, and dc glow-discharge plasmas on a chip, including a barrier-layer discharge as atom reservoir for atomic absorption spectrometry. Diagnostics for these sources are discussed and some of their figures of merit are compared with those of conventional sources. Current possibilities for introduction of gaseous samples are reported and scope for further development and outlook are both discussed.

show abstract

Section: Microwave Plasmasmentioning

confidence: 76%

The development of microplasmas for spectrochemical analysis

Broekaert

2002

Anal Bioanal Chem

View full text Add to dashboard Cite

show abstract

“…At a gas pressure (P g ) of 10 Torr, figures 2 and 3 show the calibrated (see equation ( 6)) emission intensities of H α , H β , H γ and Ar-750.4 nm lines as well as the intensity ratios between these Balmer lines and the Ar line observed as functions of input microwave power. The H atom excitation temperature, T α-β H-exc , calculated from the relative intensities of the H α and H β lines via the following equation [22,23], is also plotted in figure 3. Input microwave power (W) Here, g i is the degeneracy of the state n = i and g 3 = g 3s + g 3p + g 3d = 2 + 6 + 10 = 18, g 4 = g 4s + g 4p + g 4d + g 4f = 32.…”

Section: Variations Of Relative Intensities Between H and Ar Emission...mentioning

confidence: 99%

Atomic hydrogen determination in medium-pressure microwave discharge hydrogen plasmas via emission actinometry

Geng

Yang

Wang

et al. 2005

Plasma Sources Sci. Technol.

View full text Add to dashboard Cite

Atomic hydrogen plays an important role in the chemical vapour deposition of functional materials, plasma etching and new approaches to the chemical synthesis of hydrogen-containing compounds. This work reports experimental determinations of atomic hydrogen in microwave discharge hydrogen plasmas formed from the TM 01 microwave mode in an ASTeX-type reactor, via optical emission spectroscopy using Ar as an actinometer. The relative intensities of the H atom Balmer lines and Ar-750.4 nm emissions as functions of input power and gas pressure have been investigated. At an input microwave power density of 13.5 W cm −3 , the approximate hydrogen dissociation fractions calculated from electron-impact excitation and quenching cross sections in the literature, decreased from ∼0.08 to ∼0.03 as the gas pressure was increased from 5 to 25 Torr. The influences of the above cross sections, and the electron and gas temperatures of the plasmas on the determination of the hydrogen dissociation fraction data have been discussed.

show abstract

“…on the measurement of the Stark broadening of an atomic hydrogen line. The » (486.1 nm) line was chosen because it is generally free from plasma spectral interferences, has a sufficient intensity for measurement, and has a small half-width (0.1-0.5 nm) and extensive Stark data are available for this line (31)(32)(33). Both Doppler broadening and instrumental broadening are usually negligible compared to Stark broadening (32).…”

Section: Determination Of Relative Electron (Number) Density Was Basedmentioning

confidence: 99%

Long path atomic/ionic absorption spectrometry in an inductively coupled plasma

Mignardi¹,

Smith²,

Winefordner³

1990

Anal. Chem.

View full text Add to dashboard Cite

A novel approach was taken to increase the atomic/ionic absorption path length in an inductively coupled plasma (ICP) by using a water-cooled quartz "T-shaped" bonnet. Atomic and ionic absorption spectrometry was performed utilizing a continuum source and line sources. Absorption spectra of synthetic multielement solutions were collected with a photodiode array. Sample introduction into the ICP was accomplished with an ultrasonic nebulizer. To prevent the bonnet from cracking, low radio frequency powers were utilized (i.e., 400-600 W). Plasma diagnostics were performed to study the plasma temperature and electron number density within the "T-shaped" bonnet. Analytical figures of merit were found to be better than those obtained from previous work attempted with inductively coupled plasma atomic absorption spectroscopy and approaching that of flame atomic absorption spectroscopy.

show abstract

Diagnostical measurements in a single electrode, atmospheric pressure, microwave plasma

Cited by 25 publications

References 13 publications

The development of microplasmas for spectrochemical analysis

The development of microplasmas for spectrochemical analysis

Atomic hydrogen determination in medium-pressure microwave discharge hydrogen plasmas via emission actinometry

Long path atomic/ionic absorption spectrometry in an inductively coupled plasma

Contact Info

Product

Resources

About