Methods of Improving Glow-Discharge-Deposited a-Si1−xGex:H

1991 ◽  
Vol 219 ◽  
Author(s):  
Y. S. Tsuo ◽  
Y. Xu ◽  
E. A. Ramsay ◽  
R. S. Crandall ◽  
S. J. Salomon ◽  
...  
Keyword(s):  
Material Processing ◽  
Glow Discharge ◽  
Substrate Temperature ◽  
Gas Mixtures ◽  
Gas Composition ◽  
Processing Methods ◽  
Helium 4 ◽  
Process Gas

ABSTRACTWe have studied methods of improving glow-discharge-deposited a-Si1−x Gex :H alloys deposited using silane and germane gas mixtures. Material processing methods studied include (1) varying the substrate temperature from 170° to 280°C, (2) varying the process gas composition and pressure, (3) dilution of the feed gas by hydrogen, argon, or helium, (4) enhancing etching during deposition by adding small amounts of XeF2 vapor into the process gas, and (5) postdeposition annealing and/or hydrogenation.

scholarly journals Validation of spectroscopic gas analyzer accuracy using gravimetric standard gas mixtures: Impact of background gas composition on CO<sub>2</sub> quantitation by cavity ring-down spectroscopy

2017 ◽  
Author(s):  
Jeong Sik Lim ◽  
Miyeon Park ◽  
Jinbok Lee ◽  
Jeongsoon Lee
Keyword(s):  
Ambient Air ◽  
Gas Mixtures ◽  
Gas Composition ◽  
Optical Intensity ◽  
Negative Deviation ◽  
Gas Analyzer ◽  
Pressure Broadening ◽  
Background Gas ◽  
Standard Gas Mixtures ◽  
Cavity Ring Down

Abstract. Effect of background gas composition on the measurement of CO2 levels was investigated by wavelength-scanned cavity ring-down spectrometry (WS-CRDS) employing a spectral line centered at the R(1) of the (3 0° 1)III ← (0 0 0) band. For this purpose, eight cylinders with various gas compositions were gravimetrically and manometrically prepared within 2σ = 0.1 %, and these gas mixtures were introduced into the WS-CRDS analyzer calibrated against standards of ambient air composition. Depending on the gas composition, deviations between CRDS-determined and gravimetrically (or manometrically) assigned CO2 concentrations ranged from −9.77 to 5.36 μmol/mol, e.g., excess N2 exhibited a negative deviation, whereas excess Ar showed a positive one. The total pressure broadening coefficients (TBPCs) obtained from the composition of N2, O2 and Ar thoroughly corrected the deviations up to −0.5–0.6 μmol/mol, while these values were −0.43–1.43 μmol/mol considering PBCs induced by only N2. The use of TBPCs enhanced deviations to be corrected to ~ 0.15 %. Furthermore, the above correction linearly shifted CRDS responses for a wide extent of TPBCs ranging from 0.065 to 0.081 cm−1 atm−1. Thus, accurate measurements using optical intensity-based techniques such as WS-CRDS require TBPC-based instrument calibration.

Material Processing with Glow Discharge Beams

Nature ◽  
1968 ◽  
Vol 220 (5173) ◽  
pp. 1179-1182 ◽  
Author(s):  
R. A. DUGDALE
Keyword(s):  
Material Processing ◽  
Glow Discharge

A numerical simulation of rf glow discharge containing an electronegative gas composition

1990 ◽  
Vol 67 (7) ◽  
pp. 3264-3268 ◽  
Author(s):  
Yong‐Ho Oh ◽  
Nak‐Heon Choi ◽  
Duk‐In Choi
Keyword(s):  
Numerical Simulation ◽  
Glow Discharge ◽  
Gas Composition ◽  
Rf Glow Discharge

scholarly journals Influence of the Active Screen Plasma Power during Afterglow Nitrocarburizing on the Surface Modification of AISI 316L

Coatings ◽  
2020 ◽  
Vol 10 (11) ◽  
pp. 1112
Author(s):  
Jan Böcker ◽  
Alexander Puth ◽  
Anke Dalke ◽  
Jürgen Röpcke ◽  
Jean-Pierre H. van Helden ◽  
...  
Keyword(s):  
Surface Modification ◽  
Surface Hardness ◽  
Additional Parameter ◽  
Gas Composition ◽  
Aisi 316L ◽  
Bias Power ◽  
Process Gas ◽  
316L Steel ◽  
Plasma Nitrocarburizing ◽  
Active Screen

Active screen plasma nitrocarburizing (ASPNC) increases the surface hardness and lifetime of austenitic stainless steel without deteriorating its corrosion resistance. Using an active screen made of carbon opens up new technological possibilities that have not been exploited to date. In this study, the effect of screen power variation without bias application on resulting concentrations of process gas species and surface modification of AISI 316L steel was studied. The concentrations of gas species (e.g., HCN, NH3, CH4, C2H2) were measured as functions of the active screen power and the feed gas composition at constant temperature using in situ infrared laser absorption spectroscopy. At constant precursor gas composition, the decrease in active screen power led to a decrease in both the concentrations of the detected molecules and the diffusion depths of nitrogen and carbon. Depending on the gas mixture, a threshold of the active screen power was found above which no changes in the expanded austenite layer thickness were measured. The use of a heating independent of the screen power offers an additional parameter for optimizing the ASPNC process in addition to changes in the feed gas composition and the bias power. In this way, an advanced process control can be established.

Insights into CO2 Capture by Flue Gas Hydrate Formation: Gas Composition Evolution in Systems Containing Gas Hydrates and Gas Mixtures at Stable Pressures

2018 ◽  
Vol 6 (5) ◽  
pp. 5732-5736 ◽  
Author(s):  
Aliakbar Hassanpouryouzband ◽  
Jinhai Yang ◽  
Bahman Tohidi ◽  
Evgeny Chuvilin ◽  
Vladimir Istomin ◽  
...  
Keyword(s):  
Co2 Capture ◽  
Gas Hydrates ◽  
Gas Hydrate ◽  
Flue Gas ◽  
Hydrate Formation ◽  
Gas Mixtures ◽  
Gas Composition ◽  
Gas Hydrate Formation

Influence of Growth Parameters on the Properties of InxGa1-xAs Grown on GaAs by OMVPE

1994 ◽  
Vol 340 ◽  
Author(s):  
E. Ernest Van Dyk ◽  
Andrew W. R. Leitch ◽  
Hendrik L. Ehlers
Keyword(s):  
Optical Properties ◽  
Substrate Temperature ◽  
Atmospheric Pressure ◽  
Growth Parameters ◽  
Gas Composition ◽  
Electrical And Optical Properties ◽  
Gaas Substrates

ABSTRACTInxGa1-xAs epilayers (x < 0.2) have been grown on GaAs substrates by atmospheric pressure OMVPE. The effects of varying the substrate temperature and the gas composition on the properties of the epilayers were investigated. The investigations have shown that higher mobilities were obtained at low growth temperatures (610°C), while optimum optical properties were obtained at higher growth temperatures (690°C). Variation of the AsH3 overpressure yielded optimum electrical and optical properties at a V/III ratio of 50. 77 K mobilities higher than 42 000 cm2/V.s and photoluminescence linewidths as low as 4.4 meV were obtained for x = 0.087 and x = 0.137 epilayers, respectively.

Spectroscopic study of chemical composition of high-frequency glow-discharge in halogen-containing gas mixtures

1985 ◽  
Vol 43 (3) ◽  
pp. 971-975
Author(s):  
O. P. Gushchin ◽  
V. M. Dolgopolov ◽  
L. E. Pereverzev ◽  
D. I. Slovetskii
Keyword(s):  
Chemical Composition ◽  
Glow Discharge ◽  
Spectroscopic Study ◽  
High Frequency ◽  
Gas Mixtures

Reactive Sputter Deposition of Highly Oriented AlN Films at Room Temperature

2002 ◽  
Vol 17 (6) ◽  
pp. 1469-1475 ◽  
Author(s):  
G. F. Iriarte ◽  
F. Engelmark ◽  
I. V. Katardjiev
Keyword(s):  
Substrate Temperature ◽  
Deposition Temperature ◽  
Room Temperature ◽  
Electron Bombardment ◽  
Process Conditions ◽  
Gas Composition ◽  
Temperature Bias ◽  
Reactive Sputter Deposition ◽  
Process Pressure ◽  
Wide Range

Textured as well as epitaxial thin AlN films are of great interest for a wide range of electro-acoustic and optoelectronic applications. Reduction of the deposition temperature is of vital importance in a number of applications due to thermal budget limitations. In this work we systematically studied the influence of the process parameters on the film properties and identified the factors leading to improved film quality as well as reduced deposition temperature with pulsed direct current sputtering in an Ar/N2 atmosphere. We demonstrated that fully textured (0002) films can be grown under a wide range of conditions. At the same time the full width at half-maximum (FWHM) of the rocking curve of the (0002) XRD peak was found to vary systematically with process conditions—depostion rate, process pressure, gas composition, and substrate temperature. The best films showed a FWHM of 1.2°. We found that by far the most important factor is the arrival energy of the sputtered Al atoms, which is primarily controlled by the process pressure. We report for the first time that fully textured AlN films with a FWHM of under 2° can be grown at room temperature. Other important factors are the ion and electron bombardment of the films and substrate temperature as well as gas composition, although their influence is not as dramatic. Generally, the film quality increases with temperature. Bias and electron bombardment within a certain range also lead to better films.

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