RF Inductive Discharges

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RF Inductive Discharges
EE 403/503 Introduction to Plasma Processing
November 5, 2008
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Outline
1- RF Inductive Discharge 2- RF Capacitive
Discharge 3- MW Discharge (quasi-optical)
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AC Arc
V
Arc Hysteresis
I
The arc extinguishes at V0 but the remaining
ions reignite the arc at relatively low breakdown
voltage. Very high frequency eliminate the arc
hysteresis.
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RF Discharges
(10 KHz-30MHz)
Capacitive Coupling
Inductive Coupling
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Special Types of RF Discharges
W/cm3
B Coupled Discharge
10000
hot
1000
100
Transition from cold to hot plasmas
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Cold
1
E Coupled Discharge
0.1
0.01
103
104
105
106
107
108
109
? Hz
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RF Inductive Plasmas
Quartz Tube
H2O in
RF Power Supply
Heating Coil
Plasma
H2O out
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B(t)
? Skin depth
I(t)
j?E PjE
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Skin Depth
5000 K
10000 K
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EM Wave Plasma Interaction
Skin Depth ?
EE0e(kx-?t)
Plasma
Plasma Boundary
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Background I
Maxwell's Equations
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(No Transcript)
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Skin Depth
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Energy Coupling Parameter ?c
Coil radius, rc
Plasma radius, a
Maximum power transfer when skin depth (d) is
between 1/3 and 2/3 of the plasma radius or ? is
between approximately 2 to 4.
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Background II
1/m3
Thermonuclear Plasmas
Electron Beam
Tesla
?P 13.56 MHz
Solar Corona
?P 2.45 GHz
?P 100 MHz
?P 10 KHz
?P 10 GHz
?P 1 MHz
?P 1 THz
?P 100 Hz
Glow Discharge
Gaseous Nebulae
Interstellar Gas
Arc Discharge
MHD Generator
Ionosphere
Solid
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GEC Reference Cell
Quartz Plate
Power Supply
Interaction Layer ?
Plasma
Wafer
Base Plate
Wafer Bias Power Supply