Influence of nitrogen admixture on plasma characteristics in. The higher mobility of the electrons enables them to be more energetic and increases the plasma density. The schematic diagram of dc glow discharge plasma reactor designed by pandiyaraj et al. Karthikeyan1 1plasma laboratory, department of physics, sri vasavi college, erode, tamilnadu, india abstract. Pdf realization of soc behavior in a dc glow discharge. Characterization of a new dcglow discharge plasma setup. The dc glow discharge has been historically important, both in applications and in studying the properties of the plasma medium. The circuit used to generate the glow discharge is similar to that used before 9 and that used in low pressure glow discharges 11. Figure 2 is a schematic of the circuit used for creating and analyzing the discharge. Pdf characterization of low pressure plasmadc glow discharges. Create an ionic plasma by applying a high voltage to a glow tube.
Surface modification of pvc film using dc glow discharge. For studying the glow discharge, the usual configuration is a long glass cylinder with anode electrode at one end and cathode electrode at the other end. Sep, 2017 in our contribution, the positive column of oxygen dc glow discharge is investigated using methods of computational physics at medium pressures 200687 pa and discharge currents from 20 to 40 ma. Plasma parameters are calculated by using triple langmuir probe.
Pdf lowpressure plasma reactor which is generated for sf6, sf6he and ar gases discharges between two metal electrodes planer parallel using. Characterization of a new dcglow discharge plasma setup to. Plasma was generated in an evacuated glass tube, with circular plane disk electrodes. Princeton plasma physics laboratory, princeton, new jersey 08543. Dc glow discharge in atmospheric air as a source for.
Observations of a structureforming instability in a dcglow. Moon et al recently reported rf glow discharges at atmospheric pressure using a dielectric barrier with a u shape geometry 6. Influence of nitrogen admixture on plasma characteristics. On the basis of fluid approximation, an improved version of the model for the description of dc glow discharge plasma in the axial magnetic field was successfully developed. Related content atmospheric pressure dc glow discharge david staack, bakhtier farouk, alexander. For studying the glow discharge, the usual configuration is a long glass cylinder with anode electrode at one end and cathode electrode at. Glow discharge plasmas have been used over two decades to improve final properties of polymeric membrane surfaces dagostino 1990. Glow discharge plasma treatment is a frequently used method for cleaning, preparation, and modification of biomaterial and implant surfaces. Dc glow discharge can only generate extremely weak plasma, which happens to be suitable for surface treatment of. In this report, the initial design, simulations results. Langmuir probe measurements are performed in cylindrical dc glow discharge plasma. Cntnanostructured materials have been chosen based on cnts stability in water vapor, which is considered as a replacement for mercury vapor in glow discharge based light sources i. Dc glow discharge in atmospheric air as a source for volatile organic compounds abatement machala 2005 plasma processes and polymers wiley online library.
The use of dc glow discharges as undergraduate educational tools. The investigated continuous discharge occurring betwee. Glow discharge plasma treatment for surface cleaning and. The behavior of such oscillations associated with the anode glow has been investigated using nonlinear techniques like correlation dimension, largest lyapunov exponent, etc. Characterization of a dc atmospheric pressure normal glow. Under mentioned conditions, the attributes of the dc oxygen discharge are particular, what is based on the existence of two forms. When the voltage exceeds a value called the striking voltage, the gas ionization becomes selfsustaining, and the tube glows with a colored light. The use of dc glow discharges as undergraduate educational. Structure of a dc glow discharge anode cathode faraday k space dark dark space negative aston dark space. The dc glow discharge is maintained by the emission of secondary electrons from the. The plasma parameters in argon plasma have been studied over the pressure ranges from 0. Low temperature dc glow discharge plasma was generated in the cylindrical stainless steel chamber 50cm of length and 30 cm of internal diameter. Effect of a floating circular aperture on a dc glow discharge.
The glow discharge traps particles with an average size of 1 micron. However, the use of one or the other discharge regime for a given process will ultimately depend on a combination of factors, including. Park et al also reported on an rf glow discharge with bare electrodes 7. The films were exposed to plasma at two different exposure times with two different voltages. The ion source for the spallation neutron source of oak ridge national laboratory is required to produce a substantial amount of h current. Their history, discharge physics, and industrial applications ulrich kogelschatz1 receiued april 5, 2002. Experiments in a low pressure glow discharge on gases of environmental. Surface study on bamboo fabric using dc glow discharge. Dusty plasma, dust acoustic shocks, structure formation pacs. Pulsed dcanodic glow discharge plasma was generated.
Many scholars have carried out various studies on low pressure glow discharge experimentally and theoretically. The influence of different operating parameters such as treatment time, discharge power and operating pressure on the chemical and physical properties of the cotton fabrics is studied in detail. Low pressure dc glow discharge plasma technology is applied widely in many fields, like plasma etching, plasma material surface treatment, plasma electron beam source, plasma sputtering spraying, and so on. Tworegion computational model for dc glow discharge plasma. Surface modification with a remote atmospheric pressure. Section ii describes the experimental setup and methods, followed by the presentation of the observations in sec. A glow discharge is a kind of plasma which means partially ionized. However, dc glow discharge plasmas have certain limitations for using them in industrial applications. The model has yielded a set of analytic formulas for the physical quantities concerned from the electron and ion fluids equations and poisson equation. Discharges, sputtering, ionsurface interaction, thinfilm processing. Experimental study of the interaction between dc discharge. A dc power supply bertran 205b is connected in series to a ballast resistor and to the discharge. Glow discharge is similar to sputtering, but instead of ions from the plasma ejecting the material from the target, a chemical reaction is initiated in the gas phase by creating a radio frequency glow discharge of the reactant gas, leading to the deposition of the solid form on a substrate placed inside a chamber.
Plasma sources science and technology plasma sources sci. In this work, a dc glow discharge cell with planar electrodes as the electron source, similar to those proposed by gao etal 10,istestedwithaninlet owfromatmosphericair and using different materials and diameters of the cylindrical. To read the fulltext of this research, you can request. The schlieren imaging shows that an oblique shock can be obtained with a volumetric glow discharge on the cathode with a relatively low current as low as 50 ma. Insight into the operation of a plasma can be obtained from the dependence of the applied voltage on current. Plasma sources science and technology characterization of a dc atmospheric pressure normal glow discharge to cite this article.
Radicals have a longer lifetime in the plasma compared to ions because an ion is almost always neutralized during a collision with a surface while radicals often do not react with a surface and are reflected back into the plasma. Generation of plasma induced flow actuation by dc glow. Glow discharge plasmas exhibit various types of selfexcited oscillations for different initial conditions like discharge voltages and filling pressures. Related content dc normal glow discharges in atmospheric pressure atomic and molecular gases. Surface study on bamboo fabric using dc glow discharge plasma k. It was observed that the laserplasma interaction can only occur thermally through the electrodes. Obyrne1 1school of engineering and information technology the university of new south wales, canberra 2600, australia 2aerospace engineering and engineering mechanics the university of texas at austin, tx 78712. When the aperture is placed in front of the disk, welldefined pearshaped or spherical dust. Surface modification of pvc film using dc glow discharge plasma.
Tube of variable diameters along the axis, 2r, of 4. Dc glow discharge plasma of low pressure was generated in a glass chamber of 29cm length and 10cm internal diameter size. Surface characterization of c60 thin film induced by dc glow. Christian bradley shows us the glow discharge plasma in the st40 tokamak and how the colour changes with the pressure in the vacuum vessel. Kotp abstractin this paper, emission spectra of both positive column pc and negative glow ng regions of the dc glow. Pdf on the reliability of lowpressure dc glow discharge. The device consists of cylindrical discharge chamber with movable parallel circular copper electrodes. Realization of soc behavior in a dc glow discharge plasma sekar iyengar i. The system consists of a solid disc cathode and mesh anode. Pdf parametric investigation of nonlinear fluctuations. A onedimensional continuum model for a dc glow discharge plasma between parallelplate electrodes is presented, which is based on the local balance. Effects of nonuniform dc glow discharge system on argon. Tworegion computational model for dc glow discharge plasma title.
Low pressure linear discharges are a well known plasma pro. Observations of a structureforming instability in a dc. Glow discharge is described as selfsustaining plasma, i. Dc normal glow discharges in atmospheric pressure atomic and.
The modified bamboo fabric surface was characterized by ftir, sem, xrd and color. Color online three educational plasma devices based on dc glow discharges. Surface characterization of c60 thin film induced by dc. The axial variation of a nonuniform dc glow discharge has been investigated in an untraditional discharge system using isolated computer controlled three couples of fast double langmuir probe. The structural, optical, surface morphology and functional groups of the plasma treated and. It is seen that these oscillations go to an ordered state from a. The dc gdpau is a dc glow discharge plasma experiment that was designed, established, and operated in the physics department at ain shams university egypt. Nonlinear dust acoustic waves, shocks and stationary. Pdf glow discharges are used in a large number of application fields. Dc glow discharge in axial magnetic field at low pressures.
Pdf parametric investigation of nonlinear fluctuations in a. Dc discharges are attractive to study because the solution is time independent. Surface study on bamboo fabric using dc glow discharge plasma. The reliability of the calculated discharge characteristics is analysed by testing the different assumptions of the models and the. In a dc discharge system, a gas is energized by applying high dc. Low temperature plasma treatment on bamboo fabric has been used to improve the surface properties. Cb characterization of dc glow discharge in dusty plasma. Alves l l 2007 fluid modelling of the positive column of directcurrent glow discharges plasma sources sci. Construction and characterization of a low pressure plasma reactor using dc glow discharge 257 electrode is.
Nov 22, 2009 this paper focuses on the modification of cotton fabrics using a low pressure dc glow discharge obtained in air. The merits of such treatments are, however, strongly dependent on the process parameters. The aim of this experiment is to study and improve some properties of a printed circuit board pcb by exposing it to the plasma. Nitrogen plasma were investigated using the langmuir probe for dc glow discharge plasma at operating pressures of. Only used for sputtering system not for etchingonly used for sputtering system not for etching. Two aluminium square electrodes were fixed inside the chamber which is perpendicular to the axis, separated by 3cm distance and it is connected to the high tension dc power supply 1. Dust is incorporated into the anode glow plasma from a tray located below the anode which contained kaolin powder. To help the ion source produce this current, a dc, glow discharge plasma gun was designed using coupled fluid dynamic, heat transfer, mechanical stress and deformation, and ionelectron trajectory simulations. Vacuum of 103 mbar was maintained inside the chamber using a vacuum pump.
Above 1mhz, the heavier ions can not react to the voltage changes while the lighter electrons can follow them without problems. The 1d and 2d models show how to use the dc discharge interface to set up an analysis of a positive column. Currentvoltage characteristics of dc plasma discharges. Chemical and physical analysis of cotton fabrics plasma. Uniform dc glow discharge using cnt nanostructured cathodes. Pulsed rf discharges, glow and filamentary mode at. The plasma electron density in the axial direction has been found to be 0.
Required vacuum was maintained using fine control gas needle valve. Introductionthe study of nonequilibrium phenomena of naturally occurring 1, and laboratory plasmas 1,2 has been an active area of research in plasma physics. Higher frequencies are also used at atmospheric pressure. Dc glow discharge can only generate extremely weak plasma, which happens to be suitable for surface treatment of fragile holey carbon grids. A high voltage dc glow discharge plasma is produced in between disc shaped anode and tray shaped grounded cathode in the background of argon gas. Plasma diagnostics of a dc glow discharge using tuneable diode laser absorption spectroscopy r. Plasma diagnostics of a dc glow discharge using tuneable. It is often created by applying a voltage between two electrodes in a glass tube containing a lowpressure gas. The discharge occurs in nitrogen gas at the lefthand side of paschens curve. Dc normal glow discharges in atmospheric pressure atomic.
Only the rim of the cathode is covered by the plasma. A dc glow discharge operating with a virtual cathode is studied. The schematic diagram of dc glow discharge plasma reactor designed by. Chapter 2 the glow discharge um students repository. Tworegion computational model for dc glow discharge plasma full record. Effect of negative oxygen ions on the characteristics of.
The calculated results satisfy the practical boundary conditions. Practically this limits dc sputtering to materials of a resistivity less. Napartovich 1 1 troitsk institute for innovation and fusion research, ul. Characteristics of anodic glow pulsed plasma sciencedirect. The plasma electron density in the axial direction has been found to. To help the ion source produce this current, a dc, glowdischarge plasma gun was designed using coupled fluid dynamic, heat transfer, mechanical stress and deformation, and ionelectron trajectory simulations. A onedimensional continuum model for a dcglowdischarge plasma between parallelplate electrodes is presented, which is based on the local balance. Generation of plasma induced flow actuation by dc glowlike. Glow discharge has been used by many cryoem microscopist to treat the tem grids and make the surface hydrophilic. A glow discharge is a plasma formed by the passage of electric current through a gas.
Dc glow discharge in atmospheric air as a source for volatile. Measurements were carried out at different points along the axis of tube for different working pressures of pure argon and mixture of argonoxygen gasses to obtain the plasma density and temperature as well as plasma and. Uniform dc glow discharge using cnt nanostructured. Dc glow discharges in the lowpressure regime have long been used for gas lasers and fluorescent lamps. The dc glow discharge plasma is suitable for the surface modification of poly vinyl chloridepvc films. Glow discharge plasma properties of gases of environmental interest. Surface analysis and characterization of the plasma treated cotton fabrics is performed. Low pressure dcplasma system for the modification of polymeric. In the present work the possibilities, limitations, and risks of plas. Plasma sources science and technology dc normal glow discharges in atmospheric pressure atomic and molecular gases to cite this article. Effect of a floating circular aperture on a dc glow.
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