Micro-jet Plasma CVD Kamel Silmy Mühlleithen 20.03.2003
Micro-jet Plasma CVD
Kamel Silmy
Mühlleithen 20.03.2003
Seite 2
Micro-jet Plasma CVD
Content
• Motivation
• µjPCVD principle
• Equipment
• First experiments
§ MW, RF excitation
§ Hydrocarbon deposition
§ HMDSO/ O2• Outlook
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Micro-jet Plasma CVD
Motivation
• Localized deposition
§ write optical wave-guides
§ tribological coating (micro-gear)
§ ...
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Micro-jet Plasma CVD
pressure
Principle of µjPCVDRF
gas
• gas jet from a capillary§ HMDSO/ O2§ acetylene§ ...
• excitation§ plasma§ UV§ ...
• local deposition• „writing“ of structures
possibly with changing properties
energy
d
d
flux, p
l, Ø
• plasma parameters
• fluid dynamics parameters
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Micro-jet Plasma CVD
ParametersA B
capillarydiameter 0,1 mm 0,1 mmcross sect ion 7,9E-03 mm2 7,9E-03 mm2
length 200 mm 200 mmdistance to substrate 20 mm 10 mm
gasf lux in the capillary 10,56 sccm 6 sccmspeed inlet (206 kPa) 22,41 m/s 13 m/sspeed out let (23 kPa) 134,61 m/s ???chamber pressure 1 mbar 0,6 mbar
excitat ion t ime atspeed out let capillary 149 µs ??? µsspeed of sound (air) 61 µs 30 µs
• gas jet from capillary§ acetylene (A)§ HMDSO/ O2 (B)
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Micro-jet Plasma CVD
Gas velocity in the capillary
• length: 0.1 m
• inner diameter: 100 µm
• inlet pressure: 206 kPa
• chamber pressure: 0.1 kPa
0,00 0,02 0,04 0,06 0,08 0,100
50
100
150
200
0
20
40
60
80
100
120
140
Pres
ure
(kPa
)
X in the capillary (m)
Acethylene flow in the capillary
Ave
rage
vel
ocity
(m/s
)
Substrate Capillary
Mach disc
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Micro-jet Plasma CVD
Equipment• cross chamber
• vacuum pump (16,5 m³h-1)
• motorized x-y-z stage
• magnetron
• waveguide
• tuner
• microcapillary
§ inner diameter: 200 - 50 µm
§ length: 20 - 5 cm
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Micro-jet Plasma CVD
First Experiments
• Microwave excitation (2.45 GHz)
§ Power supply: up to 850 W
§ Plasma ignition: from 60 W
• RF excitation (13.56 MHz)
§ Power supply: up to 650 W
§ Plasma ignition: from 3 W
§ Capillary between 2 parallel electrodes
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Micro-jet Plasma CVD
Acethylene: MW, RF
• MW 80 W (left)
• Pchamber: 1 mbar
• flux: 10.50 sccm
• 20 mm substrate-capillary
• 60 s
Black deposition
Too high power
Peak deposition: less energy
• RF 10 W (right)
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Micro-jet Plasma CVD
Hydrocarbon shape RF excitation, capillary between two parallel electrodes
• 10 W • 10.50 sccm • 1 mbar • 60 s
• Double peak deposition
§ Bias: -16 V
§ 20 mm capillary to substrate
• Single peak deposition
§ Bias: 0 V
§ 9 mm capillary to substrate
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Micro-jet Plasma CVD
HMDSO/ O2 RF excitation, capillary between two parallel electrodes
• 20 W • O2: 10.50 sccm • 15 s
• HMDSO: 6 sccm
• 0.6 mbar
• Single peak
§ Bias: -170 V
§ 9 mm capillary to substrate
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Micro-jet Plasma CVD
Outlook
• SiOx and TCO (Transparency Conducted Oxide) deposition§ MW§ RF
• gas stream simulation§ Mach disc situated§ underexpanded stream
• optimal parameters for deposition§ focused
§ pressure§ power§ flux§ distance§ ...
§ shape with different capillary
CapillarySubstrate
Mach disc
Thank you