PLASMA DIAGNOSTICS
AND CHARACTERIZATION
Measurements are performed on plama
discharges operating across a wide range of operating conditions,
including pressures of 0.1 mTorr to 100's of Torr. The objectives of the
plasma measurements include:
1) Understanding the physics and
chemistry of microwave plasma discharges.
2) Verifying both compact control models and more complex
multi-dimensional numerical models.
3) Quantifying the internal plasma variables in order to improve
plasma-assisted processes.
The MNEC Center has different plasma
diagnostic techniques, including:
-
Laser spectroscopy:
LIF and CARS
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Optical emission spectroscopy:
VUV, UV, Vis, and IR
-
Gas temperature (rotational)
-
Actinometry (plasma species
concentrations)
-
Millimeter wave resonator
measurements of electron density
-
Langmuir probe measurements of
electron densities and energies
-
Microwave electric field
measurement and mapping
-
Partial pressure analysis of
plasma composition
An example of a recent plasma
diagnostic study is that of the gas temperature in an
argon/hydrogen/methane plasma used for nanocrystalline diamond
deposition. The gas temperature was measured using optical emission
spectroscopy. The particular temperature measured was the C2 molecule
rotational temperature.
Plasma Diagnostics and
Characterization References:
1. A.K. Srivastava, M. Dahimene, T.
Grotjohn, and J. Asmussen, "Experimental characterization of a
compact ECR ion source," Rev. Sci. Instrum., 63, pp. 2556-2558,
1992.
2. G. King, F.C. Sze, P. Mak, T. Grotjohn, and J. Asmussen, "Ion
and neutral energies in a multipolar ECR plasma source," J. of Sci.
and Technol., A10, pp. 1265-1269, 1992.
3. P. Mak, G. King, T. Grotjohn, and J. Asmussen, "Investigation of
the influence of electromagnetic excitation on ECR discharge
properties," J. of Vac. Sci. and Technol., A10, pp. 1281-1287,
1992.
4. F.C. Sze and J. Asmussen, "Experimental scaling laws for ECR
plasma sources," J. of Vac. Sci. and Technol., A11, pp. 1289-1295,
1993.
5. A.K. Srivastava and J. Asmussen, "Comparison of the operational
performance of a compact ECR plasma source at excitation frequencies of
2.45 GHz and MHz" J. of Vac. Sci. and Technol., A11, pp. 1307-1312,
1993.
6. A.K. Srivastava, J. Asmussen, T. Antaya and K. Harrison, "The
study of a 2.45 GHz plasma source as a plasma generator for the SCECR
Electron Cyclotron Ion Source," Rev. Sci. Instrum., 65, pp.
1135-1137, 1994.
7. A.K. Srivastava, D. Sze and J. Asmussen, "Discharge
characteristics of a five centimeter, multipolar ECR ion source,"
Rev. Sci. Instrum., 65, pp. 1749-1752, 1994.
8. A.K. Srivastava and J. Asmussen, "Measurements of the impressed
electric field inside a coaxial electron cyclotron resonance plasma
source," Rev. Sci. Instrum., 66, pp. 1028-1034, 1995.
9. J. Asmussen and W. Richardson, "Experimental performance of a
compact microwave electrothermal thruster," J. Moscow Physical
Society 1995.
10. T. A. Grotjohn, G. L. King, and W. Tan, "Microwave Plasma
Processing Machine Modeling and Diagnostics for Plasma Assisted Chemical
Vapor Deposition," J. Moscow Physical Society, 5, 55, 1995.
11. P. Mak, M.-H. Tsai, J. Natarajan, B. L. Wright, T. A. Grotjohn, F.
M. A. Salam, M. Siegel, and J. Asmussen, "Investigation of
Multipolar Electron Cyclotron Resonance Plasma Source Sensors and Models
for Plasma Control," J. of Vacuum Sci. and Technol., vol. A-14, pp.
1894-1900, 1996.
12. P. Mak and J. Asmussen, "The experimental investigation of the
matching and impressed electric field of a multipolar electron cyclotron
resonance discharge," J. Vac. Sci. and Technol., A15, pp. 154-168,
1997.
13. J. Asmussen, T. Grotjohn, P. Mak and M. Perrin, "The design and
application of electron cyclotron resonance discharges," Invited
Paper, for the 25th anniversary edition of the IEEE Trans. on Plasma
Science, PS-25, pp. 1196-1221, 1997.