Microwave Plasma Torch and its Application

1
Microwave Plasma Torch and its Application
Soon Cheon Cho, Jong Hun Kim, and Han Sup
Uhm Department of Molecular Sciences and
Technology,Ajou University, San 5 Wonchon-Dong,
Youngtong-Gu, Suwon 443-749, Korea.
Microwave Plasma Application. 2
Microwave Plasma Burner
Abstract

• Nanostructured Materials CNT

• Microwave plasma torch have a large circle of
  application.
• (1) Microwave plasma burner can effectively
  eliminate perfluorocompounds emitted
• from the semiconductor industries.
• (2) Nanocrystalline nanoparticles are directly
  synthesized in an atmospheric microwave
• plasma-torch, using gas-phase precursors
  or granules as a source material.
• (3) the production can be carried out in the
  continuous process, which makes mass
• production possible
• (4) the production system is compact,
  allowing ready operation for various
  applications.

• Plasma burner as a thermal source

• CNT synthesis
• Plasma Gas-phase synthesis
• On-line synthesis
• High growth rate

Theory
Fig. Experimental set-up. 12.5 lpm Ar 2.5 lpm
N2 plasma. (a) SEM and (b) TEM images

• Dependence of temperature in CNT synthesis process

Fig. Schematic Diagram of Electrodless
Atmospheric Microwave Plasma Torch
Fig. Plasma burner made of microwave plasma and
fuel-burning flame .
Microwave Plasma Torch
Methane
Kerosene

• Advantages of Microwave Plasma Torch
• Electrodeless.
• Frequency 2.45 GHz.
• High energy-efficiency 80.
• Commercially applicable parts.
• Easy and simple operation.
• Easy scaling-up.

Microwave Plasma Application. 1
Fig. .Growth rate along with Tf. Inset pictures
are Variation of D and G band in Raman spectrum
along with Tf.

• Abatement of SF6 and CF4 using an enhanced
  kerosene microwave plasma burner

Microwave Plasma Application. 3

• Nanostructured Materials N-Doped TiO2

• N-doped TiO2
• Doping of N as a impurities
• Band-gap narrowing
• Activation by Visible Light

Fig. Microwave Plasma torch.

• Characteristics of microwave plasma torch
• Plasma stabilization.
• The higher the power, the larger the volume
• Controllable volume and temperature by gas flow.
• Argon plasma
• Density 8 1014 cm-3
• Gas temperature 3500 K
• Air plasma
• Density 3 1013 cm-3
• Gas temperature 6000 K
• Nitrogen plasma
• Density 4 1013 cm-3
• Gas temperature 6300 K
• Production of chemically active plasma species.

Fig. Experimental set-up.
Sample A O2 10 lpm (S) N2 1 lpm (A) Sample B
N2 10 lpm (S) O2 1 lpm (A) Sample C N2 10 lpm
(S) O2 0.8 lpm (A) Sample D Pure TiO2 Powder
Providing a very reactive, unusual environment
Identification of red-shift of N-doped TiO2
CONCLUSION
FTIR spectra illustrating abatement of SF6 and
CF4 in terms of N2 flow rates by making use of a
kerosene microwave plasma burner. 1.15 kg/h 0.3
gal/h kerosene was sprayed into the plasma torch
flame stabilized by 40 lpm air at 1.4 kW plasma
power. A mixture of 30 lpm O2, nitrogen gas, and
0.1 lpm CF4 SF6 were injected into the
contaminant injector

• The microwave plasma-torch can be applied in gas
  phase at atmospheric pressure, for which an
  expensive vacuum system is not necessary
• This plasma source can be applied in the
  continuous process, which makes mass production
  possible,
• And involves a compact system allowing ready
  operation for various applications.
• It is these advantages that make it suitable for
  economical and efficient mass production.
• The present method is promising not only for the
  synthesis of nanosized of these materials but
  also for the preparation of other materials of
  nanosize

REFERENCE

• Y. C. Hong, S. C. Cho, C. U. Bang, D. H. Shin, J.
  H. Kim, H. S. Uhm, W. J. Yi,, Appl. Phys. Lett.
  88, 201502 (2006)..
• C. U. Bang, Y. C. Hong, S. C. Cho, H. S. Uhm, and
  W. J. Yi, IEEE. Trans. Plasma Sci. 34, 1751
  (2006).
• D. H. Shin, Y. C. Hong, S. C. Cho, and H.S. Uhm,
  , Phys. Plasmas 13, 114504 (2006).
• S. C. Cho, Y. C. Hong, and H. S. Uhm, Chem. Phys.
  Lett. 429, 214 (2006).
• Y. C. Hong, J. H. Kim, C. U. Bang, and H. S. Uhm,
  Phys. plasmas 12, 114501 (2005)
• Yong Cheol Honga and Han Sup Uhm, Appl. Phys.
  Lett. 88, 244101 (2006)

Fig. 2. Atmospheric pressure, 1 kW, 2.45 GHz
microwave discharges in (a) 10 lpm argon, (b) 1
lpm argon, (c) 10 lpm helium, (d) 10 lpm
nitrogen, (e) 10 lpm air, and (f) 5 lpm nitrogen
10 lpm helium.
Fig. Plot of DRE vs N2 flow rates.
Ajou University
Energy Physics research
Laboratory

• "Methane-Augmented Microwave Plasma Burner",