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In past two decades, modern industrial fabrication processes of semiconductors strongly rely on the plasma source generated by very high frequency power because of its benefits of high deposition and etching rates. In addition, large plasma chamber is needed in order to increase the production capacity. However, the underlying physics associated with high frequency power and large-scale plasma source...
A parallel 2D axisymmetric fluid model for simulating fluorocarbon (CF4) gas discharge in a dome-shaped inductively couple plasma source (ICPs) used for etching SiO2 under pressure of 20 mTorr is reported. Etching of SiO2 is an important fabrication process in semiconductor industry. Thus, etching rate and selectivity of SiO2 over Si are of extreme importance during etching. In our models, a set of...
A final pulse of hot electrons can induce preheat and shock ignition[su1} under direct drive, as recently demonstrated2 with the implicit/hybrid code ePLAS3,4. The ePLAS model follows a laser generated hot electron component (fluid or particles) through background plasma of cold fluid electrons and ions. It allows for variations in the hot electron spectrum and directivity, and can suggest tuning...
Plasma water treatment is starting to be applied in Advanced Oxidation Processes (AOP). It was experimentally established that water plasmas contain a lot of chemically active species such as OH radical, O radical, H radical which have strongly oxidized agents[su[1]}. in this study, we propose researches on electrical discharge condition having a high impulse current as well as formation of radicals...
A megabar plasma has been produced in a precisely controlled cavitation event with a repetition rate that can range from single shot to several per minute.
Complex (dusty) plasmas consist of microparticles embedded in a plasma. The microparticles acquire charges of several thousands of electrons and interact with each other. As the microparticles are usually all charged negatively, they repell each other, and no attractive forces are expected. Here, we report on experiments in which an apparent surface tension was observed that compressed the boundary...
We present self-consistent numerical fluid modeling of 2.45 GHz cold non-magnetized plasma along a plasma-dielectric in terface at conditions similar to those in cold plasma processing equipment. In such plasmas local electron plasma resonance is known to occur where the local electron density ne approaches the cut-off density nc1. Provided the bulk plasma is overdense (ne > nc), the electron density...
The propagation of ion-acoustic solitary waves in inhomogeneous magnetized plasma is investigated analytically. The fluid equations for ions have been treated by reductive perturbation analysis technique. In this formulation process we have used a space-time stretched coordinate. The system of equations has been reduced to a modified Korteweg-de-Vries (mKdV) equation. The soliton solutions are found...
The issue of use of Boltzmann relation in magnetized plasmas has been recently again brought to attention by [1, 2]. Boltzmann relation for electrons is a usual assumption in fluid plasma modeling used also in fusion device modeling and it is in general a very good approximation, even though it strictly holds only for massless electrons. But when oblique or wall parallel magnetic field is considered,...
In fluid treatments of plasma-wall-transition (PWT) problems, the system of fluid equations of a given particle species is often1−3 closed by means of an equation of the form Dp/Dt = (γp/n) Dn/Dt (“local polytropic law”), where n(x⃗, t) and p(x⃗,t) are the density and pressure, γ(⃗x,t) is called the “polytropic-coefficient function (PCF)”3, and D/Dt = ∂/∂t + ⃗u · ∇ is the Lagrangian time derivative...
The Rayleigh-Taylor instability (RTI) can be helpful in analyzing astrophysical flows, as in the case of supernova remnants interacting with the circumstellar medium. In the present work we investigate the linear Rayleigh-Taylor instability of an interface of two superposed fluids with exponential density in plane geometry. This approximation is appropriate for supernova remnants, because the temperature...
Complex plasma is the so called plasma state of soft matter. It is usually comprised of low temperature gas discharge and dust, often called dusty plasma. In our laboratory experiments we use capacitively coupled radio frequency (rf) discharges in noble gasses into which we inject mono disperse spherical particles which are a few micrometers in diameter. These particles charge up negatively and their...
The PK-4 setup uses a DC discharge to create a plasma inside a glass tube in Argon or Neon at a pressure of around 1 mbar. Plastic micro-spheres injected into the plasma collect several thousand electrons and interact with each other over a screened (Debye-Hückel) potential. This tunable interaction allows to study matter on an atomistic level in nearly every state, from crystalline (‘plasma crystal’)...
The classic examples of a system with aligned anisotropic interactions are electro- and magnetorheological ER/MR fluids, where anisotropic pair interactions between particles are induced by external electric or magnetic AC fields. ER/MR effect can be created in various physical systems, including colloids with induced dipoles, suspensions of dielectric particles, polymers, and ER complex plasmas....
The propagation of plasma bullet in a plasma jet is described under the base of fluid theory of plasma diffusion and plasma drift as well as the gas flow. The origin of plasma bullet is analyzed to be the electrostatic plasma diffusion wave propagating in the plasma column of plasma jets. The plasma diffusion waves, electron wave as well as ion wave, propagate as the form of wave-packet modulated...
The ePLAS implicit simulation code1 is being used to study various focusing aids for hot electron directivity in Fast Igintion2. The ePLAS model can follow a laser generated hot electron component (fluid or particles) through background plasma consisting of cold fluid electrons and ions. The code captures eMHD3 effects, which can enhance B-field penetration in steep density gradient regions. The E-...
Compact pulsed power of a table top size has been developed by using the magnetic pulse compression circuit with saturable cores as closing switches. This high repetitive and reliable pulsed power generator is widely used in universities, companies and institutions.
High-order accurate finite element methods are important for problems that have strong anisotropies and complicated geometries and for stiff equation systems that are coupled through large source terms. Magnetized plasma simulations of realistic devices using the multi-fluid plasma model are examples that benefit from high-order accuracy. The multi-fluid plasma model only assumes local thermodynamic...
The 24-strap ITER RF antenna is modeled with a time-domain electromagnetic simulation package [1], that faithfully represents the 3D complexity of the launcher geometry. The simulations include a cold-plasma fluid model of the edge plasma [2], with an RF sheath sub-grid model which allows for realistic behavior of plasma in contact with metallic structures such as Faraday shields [3]. This self-consistent...
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