Atomic Emission Characteristics of Laser-Induced Plasmas in an Argon Atmosphere at Reduced Pressure

1989 ◽  
Vol 43 (2) ◽  
pp. 229-234 ◽  
Author(s):  
Yasuo Iida
Keyword(s):  
Thermal Characteristics ◽  
Sample Surface ◽  
Atomic Emission ◽  
Argon Atmosphere ◽  
Emission Characteristics ◽  
Reduced Pressure ◽  
Spatially Resolved ◽  
Emissive Region ◽  
Resultant Increase ◽  
Atomic Lines

The emission characteristics of laser-induced plasma, with the use of a Q-switched ruby laser of 1.5 J, were studied in argon atmosphere at reduced pressure. The time- and spatially resolved emission profiles were measured. In argon atmosphere at reduced pressure, the emission period of plasma is elongated to over a hundred microseconds, and the emissive region expands to more than a few tens of millimeters above the sample surface. The emission intensities of atomic lines increase severalfold in an argon atmosphere, in comparison with those obtained in air at the same pressure. Moderate confinement of plasmas and a resultant increase of emission intensities are achieved at 50 Torr. These results are explained by the chemical inertness and the thermal characteristics of the argon atmosphere and the decrease in absorption of the laser pulse by the plasma plume. The re-excitation of emissive species by collisions with metastable argon atoms seems to be less important.

Theoretical and experimental study of the gradient properties and the resulting local crystalline structure and orientation in magnetron-sputtered CrAlN coatings with lateral composition and thickness gradient

2017 ◽  
Vol 50 (4) ◽  
pp. 1000-1010
Author(s):  
Bärbel Krause ◽  
Michael Stüber ◽  
Anna Zimina ◽  
Ralph Steininger ◽  
Mareike Trappen ◽  
...  
Keyword(s):  
Target Surface ◽  
Sample Surface ◽  
Composition Gradient ◽  
Face Centered Cubic ◽  
X Ray Diffraction ◽  
X Ray ◽  
Al Content ◽  
Spatially Resolved ◽  
Composition Profiles ◽  
Face Centered

Cr–Al–N coatings with a lateral composition gradient were deposited from two segmented Cr/Al targets with different segment size, thus covering the Al content range 0.22 ≲ c ≲ 0.87 and a thickness range from several hundred nanometres to several micrometres. The two-dimensional thickness and composition profiles were determined nondestructively from X-ray fluorescence maps. The results were reproduced by simulations of the flux distribution on the sample surface, combiningTRIDYNsimulations of the reactive sputter process at the target surface andSIMTRAsimulations of the subsequent transport through the gas phase. The phase formation was studied by spatially resolved X-ray diffraction and X-ray absorption spectroscopy at the Cr Kedge. Forc ≲ 0.69, a single-phase solid solution face-centered cubic (f.c.c.) (Cr,Al)N phase was found, and for 0.69 ≲ c ≲ 0.87 coexisting f.c.c. (Cr,Al)N and hexagonal close packed (h.c.p.) (Cr,Al)N phases were observed. The biaxial texture formation in nearly the entire composition range indicates a zone T growth. Four, mainly composition-dependent, texture regions were identified. All observed textures are closely related to textures reported for the h.c.p. AlN and f.c.c. CrN parent phases. Forc ≳ 0.69, a strong thickness dependence of the textures was observed. The measurements reveal an orientation relation between different f.c.c. and h.c.p. textures, indicating that local epitaxy might play a role in the structure formation.

scholarly journals Time and Spatially Resolved Spectrum Study of Laser-Induced Plasma in Reduced Pressure Atmospheres of Argon and Helium.

1994 ◽  
Vol 43 (2) ◽  
pp. 80-84 ◽  
Author(s):  
Mikio KUZUYA ◽  
Hitoshi MATSUMOTO ◽  
Hiroaki SAKANASHI ◽  
Tomohiko TAKEMOTO ◽  
Osamu MIKAMI
Keyword(s):  
Reduced Pressure ◽  
Laser Induced Plasma ◽  
Spatially Resolved

Emission Spectrographic Analysis of Surfaces with an Ion-Sputtering Source

1976 ◽  
Vol 30 (5) ◽  
pp. 510-515 ◽  
Author(s):  
M. E. Waitlevertch ◽  
J. K. Hurwitz
Keyword(s):  
Power Supply ◽  
Sample Surface ◽  
Argon Atmosphere ◽  
Concentration Profiles ◽  
Spectrographic Analysis ◽  
Ion Sputtering ◽  
Square Wave ◽  
Source Current ◽  
Depth Concentration

An ion-sputtering source was installed and evaluated as an emission spectrographic source for the analysis of metal surfaces and for the determination of in-depth concentration profiles. This source generates a direct current glow discharge in a low-pressure argon atmosphere between a hollow stainless-steel anode and the sample (the cathode) and sputters material at a controlled rate from the sample surface. The resultant spectrum of the sputtered material is recorded photographically, and the analysis is completed by conventional spectrographic techniques. The power supply of the source can be operated in either a constant dc mode or a square-wave dc mode, but better repeatability and accuracy have been achieved with the square-wave dc mode. Before any significant sputtering occurs with this source, the voltage must exceed 240 Volts, the threshold sputtering voltage. The sputtering rate increases with both source current and voltage. This source has been used for the quantitative analysis of the surface of steel products and the determination of changes in composition with depth below the surface.

X-Ray Photoemission Spectromicroscopy Of Gan And AIGan

1998 ◽  
Vol 512 ◽  
Author(s):  
G. F. Lorusso ◽  
H. Solak ◽  
F. Cerrina ◽  
J. H. Underwood ◽  
P. J. Batson ◽  
...  
Keyword(s):  
Thin Films ◽  
Vapor Deposition ◽  
Metalorganic Chemical Vapor Deposition ◽  
Chemical Vapor ◽  
Sample Surface ◽  
Photoemission Spectroscopy ◽  
Chemical Inhomogeneity ◽  
X Ray ◽  
Spatially Resolved ◽  
First Time

ABSTRACTWe investigate here for the first time GaN and AIGaN films by using x-ray photoemission spectromicroscopy. As compared to conventional x-ray photoemission spectroscopy (XPS), spectromicroscopy can provide spatially resolved information on the chemical composition of the sample surface. The experimental results where obtained by using MAXIMUM, a scanning photoemission microscope installed on 12.0 undulator beamline at the Advanced Light Source (ALS), Berkelely, allowing for a spatial resolution of 100 nm. We investigate here GaN and AlGaN thin films grown on sapphire substrate by metalorganic chemical vapor deposition (MOCVD). The results clearly indicate the great potential of spectromicroscopy in investigating chemical inhomogeneity, inpurities and localization in GaN and AlGaN thin films.

scholarly journals Химический анализ зоопланктона методом лазерно-искровой эмиссионной спектроскопии без использования образцов сравнения

2020 ◽  
Vol 128 (9) ◽  
pp. 1231
Author(s):  
Н.И. Сушков ◽  
Н.В. Лобус ◽  
И.В. Селиверстова ◽  
Т.А. Лабутин
Keyword(s):  
Inductively Coupled Plasma ◽  
Transport Model ◽  
Radiation Transport ◽  
Atomic Emission ◽  
Stark Broadening ◽  
Inductively Coupled ◽  
Breakdown Spectroscopy ◽  
Atomic Lines ◽  
Radiation Transport Model

This study deals with the determination of ratios of light metals (Li, Na, K, Mg, and Ca) in zooplankton (Calanus spp.) by calibration free laser-induced breakdown spectroscopy, assuming local thermodynamic equilibrium. The temperature of laser-induced plasma of zooplankton was derived from rotation-vibration bands of CN, and the electron density was calculated by Stark broadening of Mg I 383.23 nm, Li I 610.37 nm, and Ca II 396.85 nm lines. The synthetic spectra calculated with a radiation transport model for the experimental values of T and Ne were used for a selection of analytical atomic lines free from self-absorption. We compared the obtained data with the results of atomic emission and mass spectrometry with inductively coupled plasma. We also discussed the influence of ionization equilibrium on the accuracy of the results. We propose the presented method for direct semi-quantitative determination of Li, Mg, and Ca ratios in zooplankton.

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