Role of Laser Pre-pulse and Target Density Modification on the Acceleration of Protons from a Hydrogen Plasma Sphere

Here we present two ways of preparing lateral (in plane) silicon nanowires with the help of gold nanoislands catalysed plasma enhanced chemical vapour deposition. The role of the applied potential and eventual consecutive hydrogen plasma treatment is tested together with the thickness of the thin Au layer used for self-organised preparation of Au nanoislands.

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Plasma Chemistries for Dry Etching GaN, AIN, InGaN and InAIN

MRS Proceedings ◽

10.1557/proc-421-309 ◽

1996 ◽

Vol 421 ◽

Author(s):

S. J. Pearton ◽

C. B. Vartuli ◽

J. W. Lee ◽

S. M. Donovan ◽

J. D. MacKenzie ◽

...

Keyword(s):

Hydrogen Plasma ◽

Critical Factor ◽

Dry Etching ◽

Ion Energies ◽

Volatile Products ◽

Etch Rates

AbstractEtch rates up to 7,000Å/min. for GaN are obtained in Cl2/H2/Ar or BCl3/Ar ECR discharges at 1–3mTorr and moderate dc biases. Typical rates with HI/H2 are about a factor of three lower under the same conditions, while CH4/H2 produces maximum rates of only ˜2000Å/min. The role of additives such as SF6, N2, H2 or Ar to the basic chlorine, bromine, iodine or methane-hydrogen plasma chemistries are discussed. Their effect can be either chemical ( in forming volatile products with N) or physical ( in breaking bonds or enhancing desorption of the etch products). The nitrides differ from conventional III-V's in that bondbreaking to allow formation of the etch products is a critical factor. Threshold ion energies for the onset of etching of GaN, InGaN and InAlN are ≥75eV.

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Generation of Short-scale Electrostatic Fields in the Solar Atmosphere and the Role of Helium Ions

The Astrophysical Journal ◽

10.3847/1538-4357/ac05cb ◽

2021 ◽

Vol 922 (1) ◽

pp. 48

Author(s):

H. Saleem ◽

Shaukat Ali Shan ◽

A. Rehman

Keyword(s):

Shear Flow ◽

Transition Region ◽

Electric Fields ◽

Hydrogen Plasma ◽

Theoretical Models ◽

Inhomogeneous Field ◽

Helium Ions ◽

Low Frequencies ◽

Short Scale

Abstract Theoretical models are presented to show that expansion of plasma in the radial direction from a denser solar surface to a rarefied upper atmosphere with short-scale inhomogeneous field-aligned flows and currents in the form of thin threads itself is an important source of electrostatic instabilities. Multifluid theory shows that the shear flow–driven purely growing electric fields appear in the transition region. On the other hand, plasma kinetic theory predicts that the short-scale current sheets (or filaments) produce current-driven electrostatic ion acoustic (CDEIA) waves in the hydrogen plasma of the transition region that damp out in the system through wave–particle interactions and increase the temperature. Similar processes take place in the solar corona and act positively for increasing the temperature further and maintaining it. The shear flow–driven instabilities and CDEIA waves have short perpendicular wavelengths of the order of 1 m and low frequencies of the order of 1 or several Hz when the ions’ shear flow scale length is considered to be of the order of 1 km. It is pointed out that the purely growing fluid instabilities turn into oscillatory instabilities and the growth rates of kinetic CDEIA wave instabilities are reduced when the dynamics of 10% helium ions is taken into account along with 90% hydrogen ions. Therefore, the role of helium ions should not be ignored in the study of wave dynamics in solar plasma.

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Influence of Hydrogen Plasma Treatment on He Implantation-Induced Nanocavities in Silicon

MRS Proceedings ◽

10.1557/proc-792-r3.32 ◽

2003 ◽

Vol 792 ◽

Author(s):

A. Vengurlekar ◽

S. Ashok ◽

C. L. Liu ◽

E. Ntsoenzok ◽

M. F. Barthe ◽

...

Keyword(s):

Electron Cyclotron Resonance ◽

Minority Carrier ◽

Hydrogen Plasma ◽

Void Formation ◽

Minority Carrier Lifetime ◽

Enhancement Effect ◽

Compliant Substrates ◽

Mismatched Heteroepitaxy ◽

Established Technique

ABSTRACTHe implantation followed by thermal anneal is a well-established technique for creating layers or bands of cavities in silicon. This process is a consequence of the interaction between He and ion-implant-induced vacancies. Applications of such cavity layers include gettering and localized minority carrier lifetime control, and compliant substrates for lattice-mismatched heteroepitaxy. Studies have shown that the presence of interstitial-type defects can lead to the shrinkage of He-cavities due to the interstitial capture by the cavities. However, few of them deal with the interaction of cavities with vacancies. Here we present results on the formation of He-cavities in Si in the presence of atomic hydrogen and vacancies produced by effusion of hydrogen. Following a helium implant, samples were hydrogenated with an electron cyclotron resonance (ECR) hydrogen plasma. Control samples without any hydrogenation were also used. We studied the influence of hydrogen on void morphology. While hydrogen enhances void size at higher energy implants, the enhancement effect is absent in lower energy implants. The results underscore the role of vacancies in void formation and growth.

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Role of Hydrogen Plasma during Growth of Hydrogenated Microcrystalline Silicon: In Situ UV-Visible and Infrared Ellipsometry Study

Japanese Journal of Applied Physics ◽

10.1143/jjap.33.5590 ◽

1994 ◽

Vol 33 (Part 1, No. 10) ◽

pp. 5590-5598 ◽

Cited By ~ 44

Author(s):

Hajime Shirai ◽

Bernard Drévillon ◽

Isamu Shimizu

Keyword(s):

Hydrogen Plasma ◽

Microcrystalline Silicon ◽

Infrared Ellipsometry ◽

Uv Visible

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Role of hydrogen plasma on electrical and optical properties of ZGO, ITO and IZO transparent and conductive coatings

Thin Solid Films ◽

10.1016/j.tsf.2005.12.057 ◽

2006 ◽

Vol 511-512 ◽

pp. 295-298 ◽

Cited By ~ 75

Author(s):

L. Raniero ◽

I. Ferreira ◽

A. Pimentel ◽

A. Gonçalves ◽

P. Canhola ◽

...

Keyword(s):

Optical Properties ◽

Hydrogen Plasma ◽

Electrical And Optical Properties ◽

Conductive Coatings

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Role of the hydrogen plasma treatment in layer-by-layer deposition of microcrystalline silicon

Applied Physics Letters ◽

10.1063/1.120324 ◽

1997 ◽

Vol 71 (23) ◽

pp. 3403-3405 ◽

Cited By ~ 58

Author(s):

K. Saitoh ◽

M. Kondo ◽

M. Fukawa ◽

T. Nishimiya ◽

A. Matsuda ◽

...

Keyword(s):

Plasma Treatment ◽

Hydrogen Plasma ◽

Layer By Layer ◽

Microcrystalline Silicon ◽

Layer Deposition

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Influence of Hydrogen plasma on electrical and optical properties of transparent conductive oxides.

MRS Proceedings ◽

10.1557/proc-862-a21.10 ◽

2005 ◽

Vol 862 ◽

Author(s):

L. Raniero ◽

A. Gonçalves ◽

A. Pimentel ◽

I. Ferreira ◽

S. Zhang ◽

...

Keyword(s):

Solar Cells ◽

Figure Of Merit ◽

High Current Density ◽

Hydrogen Plasma ◽

Optical Transmittance ◽

Nanocrystalline Silicon ◽

High Current ◽

Electrical Behavior ◽

Electrical And Optical Properties

AbstractIn this work we study the optical and electrical behavior of ZnO:Ga, ITO and IZO films deposited on glass after sustaining different hydrogen plasma conditions and exposure times. This work was complemented by analyzing the surface morphology of the set of films, which allow us to determine the role of hydrogen plasma on the film's properties such as Hall mobility, free carrier concentration, sheet resistance, optical transmittance, figure of merit and state of the surface. Apart from that, the performances of solar cells using an intrinsic layer constituted by nanocrystalline silicon will be also presented. The data show that the electrical properties of solar cells were improved by using ZnO:Ga as front contact, allowing a high current density collection and single pin solar cells with efficiencies exceeding 11%.

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