Flute growth rate of plasma jet in mirror machine

AbstractFast (7 nm/s) deposition of amorphous hydrogenated silicon with a midgap density of states less than 1016 cm-3 and an Urbach energy of 50 meV has been achieved using a remote argon/hydrogen plasma. The plasma is generated in a dc thermal arc (0.5 bar, 5 kW) and expands into a low pressure chamber (20 Pa) thus creating a plasma jet with a typical flow velocity of 103 m/s. Pure silane is injected into the jet immediately after the nozzle, in a typical flow mixture of Ar:H2:SiH4=55:10:10 scc/s. As the electron temperature in the recombining plasma is low (typ. 0.3 eV), silane radicals are thought to be produced mainly by hydrogen abstraction.Material quality in terms of refractive index, conductivity, microstructure parameter and optical bandgap was found to increase monotonously with substrate temperature, even up to 350 °C; for practically all low growth rate deposition schemes an optimum around 250 °C is observed. It will be argued that this behavior is consistent with a simple kinetic model involving physisorption and hopping, growth on dangling bonds and thermal desorption of hydrogen.

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Morphology of Diamond Films Grown by DC Plasma Jet CVD

MRS Proceedings ◽

10.1557/proc-162-115 ◽

1989 ◽

Vol 162 ◽

Cited By ~ 3

Author(s):

Kazuaki Kurihara ◽

Ken-Ichi Sasaki ◽

Motonobu Kawarada ◽

Nagaaki Koshino

Keyword(s):

Growth Rate ◽

Microwave Plasma ◽

Diamond Films ◽

High Growth ◽

Plasma Jet ◽

High Growth Rate ◽

Plasma Cvd ◽

Dc Plasma ◽

Synthesis Conditions ◽

Microwave Plasma Cvd

ABSTRACTIt is well known that diamond films synthesized from the gas phase have well defined crystal habits which are affected strongly by synthesis conditions. Though there have been many studies of the morphologies of diamond films synthesized by microwave plasma CVD [1,2,3], there have been relatively few reports on the morphologies of these films grown using new high growth rate techniques such as DC plasma jet CVD [4]. Morphology control is very important to keep flat surface, when producing thick diamond films by high growth rate techniques. In this paper we report our investigation of the morphology and growth of diamond films synthesized by DC plasma jet CVD.

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Single Crystal Diamond Deposited by Dual Radio-Frequency Plasma Jet CVD with High Growth Rate

Crystals ◽

10.3390/cryst9010032 ◽

2019 ◽

Vol 9 (1) ◽

pp. 32 ◽

Cited By ~ 2

Author(s):

Hao Liu ◽

Jia-jun Li ◽

Zhen-rui Li ◽

Kai Xu ◽

Zheng-jia Chen ◽

...

Keyword(s):

Growth Rate ◽

Radio Frequency ◽

Single Crystal ◽

Emission Spectra ◽

High Growth ◽

Optical Emission ◽

Plasma Jet ◽

Methane Flux ◽

High Growth Rate ◽

Single Crystal Diamond

Single crystal diamonds were deposited on high pressure high temperature (HPHT) substrate with high growth rate, up to 18.5 μm/h, by using dual radio-frequency inductive coupled plasma jet. The methane flux was found to influence the growth rate of single crystal diamond. The reason for this might be ascribed to the electron temperature increase, raising the flux of methane, based on the plasma diagnosis results by optical emission spectra (OES). The results of Raman spectroscopy and the X-ray rocking-curve indicated that as-deposited diamonds are of good quality.

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Effect of Growth Parameters on Single Crystal Diamond Deposition by DC Arc Plasma Jet CVD

Advanced Materials Research ◽

10.4028/www.scientific.net/amr.490-495.3094 ◽

2012 ◽

Vol 490-495 ◽

pp. 3094-3099 ◽

Cited By ~ 2

Author(s):

Li Fu Hei ◽

Jie Liu ◽

Fan Xiu Lu ◽

Cheng Ming Li ◽

Jian Hua Song ◽

...

Keyword(s):

Growth Rate ◽

Surface Morphology ◽

Single Crystal ◽

Growth Parameters ◽

Plasma Jet ◽

Typical Feature ◽

Arc Plasma ◽

Diamond Sample ◽

Single Crystal Diamond ◽

Dc Arc

Homoepitaxial diamond layers were grown on commercial 3.5 x 3.5 x 1.2 mm3 HPHT synthetic type Ib (100) single crystal diamond plates using a DC Arc Plasma Jet CVD operating at gas recycling mode. The effects of substrate temperature and CH4/H2 ratio on the surface morphology, the growth rate and the quality of the synthesized diamond have been studied using optical microscopy and Raman spectroscopy. With no intentional nitrogen added, the growth rate up to 12.3µm/h has been obtained in the single crystal diamond sample deposited at 1000 °C with CH4/H2=0.625%, exhibiting relatively smooth surface morphology without any growth hillocks nor non-epitaxial crystallites, and presenting the typical feature of the epitaxial step-flow growth. The full width at half maximum (FWHM) of the Raman spectra was 2.08 cm-1, which was close to that of the natural type IIa single crystal diamond.

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Development of a Multihole Atmospheric Plasma Jet for Growth Rate Enhancement of Broccoli Seeds

Processes ◽

10.3390/pr9071134 ◽

2021 ◽

Vol 9 (7) ◽

pp. 1134

Author(s):

Khattiya Srakaew ◽

Artit Chingsungnoen ◽

Waraporn Sutthisa ◽

Anthika Lakhonchai ◽

Phitsanu Poolcharuansin ◽

...

Keyword(s):

Growth Rate ◽

Atmospheric Pressure ◽

Seed Treatment ◽

Treatment Time ◽

Atmospheric Pressure Plasma ◽

Plasma Jet ◽

Atmospheric Plasma ◽

Atmospheric Pressure Plasma Jet ◽

Pressure Plasma ◽

Significant Difference

This work aims to develop a multihole atmospheric pressure plasma jet (APPJ) device to increase the plasma area and apply it to a continuous seed treatment system. Broccoli seed was used to study the effects of an atmospheric pressure plasma jet on seed germination and growth rate. An argon flow rate of 4.2 lpm, a plasma power of 412 W, and discharge frequency of 76 kHz were used for seed treatment. The contact angle decreased strongly with the increase in treatment time from 20 s to 80 s. The broccoli seed’s outer surface morphology seemed to have been slightly modified to a smoother surface by the plasma treatment during the treatment time of 80 s. However, the cross-sectional images resulted from Synchrotron radiation X-ray tomographic microscopy (SRXTM) confirmed no significant difference between seeds untreated and treated by plasma for 80 s. This result indicates that plasma does not affect the bulk characteristics of the seed but does provide delicate changes to the top thin layer on the seed surface. After seven days of cultivation, the seed treated by plasma for 30 s achieved the highest germination and yield.

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High Growth Rate Synthesis of High Quality Diamond Film by Arc Discharge Plasma Jet CVD.

Journal of the Japan Society for Precision Engineering ◽

10.2493/jjspe.67.2032 ◽

2001 ◽

Vol 67 (12) ◽

pp. 2032-2036

Author(s):

Atsushi HIRATA ◽

Atsushi YOSHIDA

Keyword(s):

Growth Rate ◽

Diamond Film ◽

Discharge Plasma ◽

Arc Discharge ◽

High Growth ◽

Plasma Jet ◽

High Growth Rate ◽

High Quality

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Hydrogen Injection in ETP Plasma Jet for Fast-Deposition of High-Quality a-Si:H

MRS Proceedings ◽

10.1557/proc-808-a9.54 ◽

2004 ◽

Vol 808 ◽

Author(s):

A.M.H.N. Petit ◽

R.A.C.M.M. van Swaaij ◽

M.C.M. van de Sanden

Keyword(s):

Growth Rate ◽

Hydrogen Content ◽

Growth Rates ◽

Plasma Chemistry ◽

High Growth ◽

Plasma Jet ◽

Solar Cell Application ◽

Microstructure Parameter ◽

Strong Relation ◽

Defect Densities

ABSTRACTWe have used a cascaded-arc expanding thermal plasma (ETP) to produce thin films of amorphous silicon at high growth rates (> 3 nm/s). Here, we present a study of the effect on material properties of hydrogen injection in the nozzle, i.e., at the exit of the arc where the plasma expands into the reactor chamber. The advantage of using extra H2 in the nozzle is that the plasma chemistry and pressure in the arc remain unchanged, whilst higher growth rates and a material with low defect densities can be obtained.We observe that with an increase of substrate temperature the growth rate decreases due to densification of the material. This densification is accompanied by a reduction of the hydrogen content and of the microstructure parameter. Further we observe that hydrogen content decreases with higher growth rate. A strong relation is found between the light conductivity and the microstructure parameter indicating a large void fraction in samples grown at low temperature.We have been able to grow a-Si:H material, with H2 in the nozzle, at 350°C and 3 nm/s with a light conductivity of 1.2 × 10−5 Ω1cm−1, which can be suitable for solar-cell application.

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Influence of plasma power over growth rate and grain size during diamond deposition using DC arc plasma jet CVD

Thin Solid Films ◽

10.1016/s0040-6090(03)00157-3 ◽

2003 ◽

Vol 429 (1-2) ◽

pp. 108-113 ◽

Cited By ~ 4

Author(s):

T.B. Huang ◽

W.Z. Tang ◽

F.X. Lu ◽

N. Ali ◽

J. Gracio

Keyword(s):

Growth Rate ◽

Grain Size ◽

Plasma Jet ◽

Arc Plasma ◽

Plasma Power ◽

Diamond Deposition ◽

Dc Arc

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The threshold energy for atom displacement in fcc metals

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100175788 ◽

1990 ◽

Vol 48 (4) ◽

pp. 530-531

Author(s):

Wilfried Sigle ◽

Matthias Hohenstein ◽

Alfred Seeger

Keyword(s):

Growth Rate ◽

Elevated Temperatures ◽

Threshold Energy ◽

Dislocation Loops ◽

Absolute Minimum ◽

Voltage Electron ◽

Atom Displacement ◽

Electron Microscopes ◽

Fcc Metal

Prolonged electron irradiation of metals at elevated temperatures usually leads to the formation of large interstitial-type dislocation loops. The growth rate of the loops is proportional to the total cross-section for atom displacement,which is implicitly connected with the threshold energy for atom displacement, Ed . Thus, by measuring the growth rate as a function of the electron energy and the orientation of the specimen with respect to the electron beam, the anisotropy of Ed can be determined rather precisely. We have performed such experiments in situ in high-voltage electron microscopes on Ag and Au at 473K as a function of the orientation and on Au as a function of temperature at several fixed orientations.Whereas in Ag minima of Ed are found close to <100>,<110>, and <210> (13-18eV), (Fig.1) atom displacement in Au requires least energy along <100>(15-19eV) (Fig.2). Au is thus the first fcc metal in which the absolute minimum of the threshold energy has been established not to lie in or close to the <110> direction.

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