Measurement for dissociation ratio of source gases in plasmas using a quartz sensor

Suzuki, Atsushi; Nonaka, Hidehiko

doi:10.1016/j.vacuum.2010.01.004

Cited by 11 publications

(7 citation statements)

References 25 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…We have reported changes in gas composition in plasmas using Q-sensor measurements. [24][25][26][27][28][29][30] The Q-sensor output is calculated from the impedance of a quartz oscillator and is dependent on the pressure, temperature, molecular weight, and viscosity of the measured gas. 31) Therefore, the pressureand temperature-normalized Q-sensor output (NQO) reflect the molecular weight and viscosity of the measured gas, and thus, the change in the gas composition with plasma can be observed from the change in NQO.…”

Section: Introductionmentioning

confidence: 99%

“…For example, the gas decomposition can be derived from a comparison of the NQO change with gas analysis results. 27) To obtain information on only stable gas molecules in plasmas, a filter is used with the quartz oscillator to prevent reactive species from interacting with the quartz oscillator, so that only stable molecules are detected by the Q-sensor. [24][25][26][27][28][29][30] However, when all species in the plasma can be detected using a Q-sensor without a filter, information on the gas composition, including reactive species, can be obtained.…”

Section: Introductionmentioning

confidence: 99%

“…27) To obtain information on only stable gas molecules in plasmas, a filter is used with the quartz oscillator to prevent reactive species from interacting with the quartz oscillator, so that only stable molecules are detected by the Q-sensor. [24][25][26][27][28][29][30] However, when all species in the plasma can be detected using a Q-sensor without a filter, information on the gas composition, including reactive species, can be obtained. The N 2 partial-pressure dependence of Q-sensor measurements with and without a filter in N 2 -H 2 plasmas was previously revealed, through the correlation of the results of gas analyses and optical emission spectroscopy.…”

Section: Introductionmentioning

confidence: 99%

See 2 more Smart Citations

Stable Molecules in N₂–H₂Plasmas Measured Using a Quartz Sensor

Suzuki

Asahina

2013

Jpn. J. Appl. Phys.

Self Cite

View full text Add to dashboard Cite

Stable molecules of N2, H2, and NH3 in N2–H2 plasmas were investigated using a quartz sensor (Q-sensor). Changes in the pressure- and temperature-normalized Q-sensor output (NQO) induced by plasma with radio-frequency (rf) input power were measured near plasma electrodes and shown to correlate to the relative ion signal intensity from NH3. The results confirm that gas composition changes in N2–H2 plasmas can be successfully measured from the NQO changes using the Q-sensor. The spatial distribution of NQO indicates that NH3 molecules are produced near plasma electrodes rather than by secondary gas reactions in the plasma, which also means that Q-sensor measurements can provide information regarding stable gas molecules in plasma.

show abstract

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

Section: Introductionmentioning

confidence: 99%

See 1 more Smart Citation

Stable Molecules in N₂–H₂Plasmas Measured Using a Quartz Sensor

Suzuki

Asahina

2013

Jpn. J. Appl. Phys.

Self Cite

View full text Add to dashboard Cite

show abstract

“…In addition, ρ can be expressed as a product of the molecular weight (M) and pressure (P) of the gas. Therefore, the output from a quartz oscillator depends on ç and M. This means that the Qgauge can detect not only the change in pressure, but also the content of the gas, making it applicable to hydrogen sensing, hydrogen concentration measurements, partial concentration measurements of binary gases, and plasma diagnostics [2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17][18][19][20].…”

Section: Introductionmentioning

confidence: 99%

Humidity Calibration for a Pressure Gauge Using a Temperature-Stable Quartz Oscillator

Suzuki

2016

Applied Science and Convergence Technology

Self Cite

View full text Add to dashboard Cite

Humidity calibration for a temperature-stable quartz oscillator (TSQO) was investigated to exclude the influences of relative humidity on the TSQO output in order to use the corresponding devices outdoors. The TSQO output is a voltage that is inversely proportional to the electric impedance of the quartz oscillator, which depends on the viscosity and density of the measured gas. The TSQO output was humidity calibrated using its humidity dependence, which was obtained by varying the relative humidity (RH) from 0 to 100 RH% while other conditions were kept constant. The humidity dependencies of the TSQO output were fit by a linear function. Subtracting the change in the TSQO output induced by the change in humidity, calculated with the function from the experimentally measured TSQO output for a range of 0-100RH%, eliminated the influence of humidity on the TSQO output. The humidity calibration succeeded in reducing the fluctuations of the TSQO output from 0.4-3% to 0.1-0.3% of the average values for a range of 0-100RH%, at constant temperatures. The necessary stability of the TSQO output for application in hydrogen sensors was below one-third of the change observed for a hydrogen leakage of 1 vol.% hydrogen concentration, corresponding to 0.33% of the change in each background. Therefore, the results in this study indicate that the present humidity calibration effectively suppresses the influence of humidity, for the TSQO output for use as an outdoor hydrogen sensor.

show abstract

“…Quartz sensor (Q-sensor) measurement can detect changes in the gas compositions of plasmas because the pressureand temperature-normalized Q-sensor output (NQO) depends only on the viscosity and molecular weight of the measured gas. [1][2][3][4][5][6][7][8] Q-sensor measurement can selectively derive only the information on stable gas molecules in plasmas when a mesh cover is used to prevent reactive chemical species in the plasmas from reaching the quartz oscillator, which is a sensing device installed in the Q-sensor. Q-sensor measurement is a useful plasma diagnostic method, although it cannot yield information on each chemical species in plasmas, which can be derived by gas analysis using a mass spectrometer.…”

Section: Introductionmentioning

confidence: 99%

Dependence of composition of stable molecules in N₂–H₂plasmas on nitrogen gas flow rate ratio measured using a quartz sensor

Suzuki¹,

Asahina²

2014

Jpn. J. Appl. Phys.

Self Cite

View full text Add to dashboard Cite

Compositions of stable molecules in N 2 -H 2 plasmas measured using a quartz sensor (Q-sensor) were compared with those measured using a quadrupole mass spectrometer (QMS) under various nitrogen gas flow rate ratio to determine the applicability of Q-sensor measurement to N 2 -H 2 plasmas. The nitrogen flow rate ratio dependence of the Q-sensor results obtained 20 mm from the edge of the plasma electrodes (Z = 20 mm) tended to agree more qualitatively with the NH 3 density measured by QMS compared with those measured at 70 mm. For pure nitrogen or hydrogen plasma, the results measured at Z = 20 mm differed from those of gas analyses using QMS. The analysis indicated that Q-sensor results obtained near discharges with various nitrogen flow rate ratios reflect information on stable molecules such as N 2 , H 2 , and NH 3 but yield information on other stable molecules or other chemical species in pure N 2 and H 2 plasmas.

show abstract

Measurement for dissociation ratio of source gases in plasmas using a quartz sensor

Cited by 11 publications

References 25 publications

Stable Molecules in N₂–H₂Plasmas Measured Using a Quartz Sensor

Stable Molecules in N₂–H₂Plasmas Measured Using a Quartz Sensor

Humidity Calibration for a Pressure Gauge Using a Temperature-Stable Quartz Oscillator

Dependence of composition of stable molecules in N₂–H₂plasmas on nitrogen gas flow rate ratio measured using a quartz sensor

Contact Info

Product

Resources

About

Measurement for dissociation ratio of source gases in plasmas using a quartz sensor

Cited by 11 publications

References 25 publications

Stable Molecules in N2–H2Plasmas Measured Using a Quartz Sensor

Stable Molecules in N2–H2Plasmas Measured Using a Quartz Sensor

Humidity Calibration for a Pressure Gauge Using a Temperature-Stable Quartz Oscillator

Dependence of composition of stable molecules in N2–H2plasmas on nitrogen gas flow rate ratio measured using a quartz sensor

Contact Info

Product

Resources

About

Stable Molecules in N₂–H₂Plasmas Measured Using a Quartz Sensor

Stable Molecules in N₂–H₂Plasmas Measured Using a Quartz Sensor

Dependence of composition of stable molecules in N₂–H₂plasmas on nitrogen gas flow rate ratio measured using a quartz sensor