Oxford Plasmalab 80 Plus User manual

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Standard Operating Manual
___________________________________________________________
Oxford Plasmalab 80 Plus Plasma Etcher

NANOSYSTEMFABRICATIONFACILITY(NFF),HKUST
Version1.0Pa
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Contents
1. Picture and Location
2. Process Capabilities
2.1 Cleanliness Standard
2.2 Available Etching Materials
2.3 Performance of the Oxford Plasmalab 80 Plus Plasma Etcher
3. Contact List and How to Become a Qualified User
3.1 Emergency Responses and Communications
3.2 Training to Become a Qualified User
4. Operating Procedures
4.1 System Description
4.2 Safety Warnings
4.3 Initial System Checks
4.4 Status Checks
4.5 Venting the Chamber (Before Loading Wafers)
4.6 Opening the Process Chamber
4.7 Inspecting the Chamber Before Use
4.8 Load Wafers
4.9 Closing the Process Chamber
4.10 Pumping Down the System for Dry etching
4.11 Start your Dry Etching Process
4.12 Venting the Chamber (Before Unloading Wafers)
4.13 Pumping the System Down for Idle
5. Appendix

NANOSYSTEMFABRICATIONFACILITY(NFF),HKUST
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1. Picture and Location
Chamber
Computer
OxfordPlasmalab80
PlusPlasmaEtcher
Fig 1: This tool is located at NFF Enterprise Center Cleanroom Room 4162
2. Process Capabilities
2.1 Cleanliness Standard
Oxford Plasmalab 80 Plus Plasma Etcher is “Non-Standard” equipment for dry
etching process.
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2.2 Available Etching Materials
The following sources are available in Oxford Plasmalab 80 Plus Plasma Etcher.
LTO, Thermo Oxide, Silicon Nitrite, Poly-silicon and Silicon on 4” wafer or small
piece sample.
NOTE: Consult NFF EC staff prior to do new materials other than above listed. Hazardous or
Radioactive materials are not allowed to be etched in Oxford Plasmalab 80 Plus Plasma Etcher.
2.3 Performance of the Oxford Plasmalab 80 Plus Plasma Etcher
What CAN do:
Oxford RIE 80+ can etch thin films thickness (≥400A thick) or thick films
thickness (≤100um thick).
What CANNOT do:
Oxford Plasmalab 80 Plus Plasma Etcher could not replace ICP DRIE for
etching thick films, e.g. over 100um
It could not be used for photoresist Stripping, due to photoresist is for mask
protection only.
Users cannot modify the recipes’ parameters, such as chamber pressure, RF
power, process gas flow and chiller temperature.
Process time cannot over 20 minutes per run and 5 -10 minutes s allowed for
chamber cooling.

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3. Contact List and How to Become a User
3.1 Emergency Responses and Communications
Security Control Center: 2358-8999 (24hr) & 2358-6565 (24hr)
Safety Officer: Mr. Wing Leong CHUNG 2358-7211 & 64406238
Deputy Safety Officer: Mr. Man Wai LEE 2358-7900 & 9621-7708
NFF EC Technician: Mr. Peter Yiu Cheong PUN 2358-7225 & 2358-7218
NFF Phase 2 Technician: Mr. Wilson Pui Keung YIP 2358-7894
3.2 Training to Become a Qualified User
Please follow the procedure below to become a qualified user.
1. Read all materials on the NFF website concerning the Oxford RIE 80+.
2. Send an e-mail to NFF requesting Oxford RIE 80+ safety operation training.
Scheduling can take up to several weeks due to the many requests coming in
for this tool.
4. Operating Procedures
4.1 System Description
Oxford Plasmalab 80 Plus Plasma Etcher is a plasma processing system, which can be
configured to carry out reactive ion etching(RIE).
The chamber arrangement for a typical RIE process is shown as below:
The electrode is powered by a 13.56 MHz RF generator. The associated
auto-matching tuner unit is positioned close to the driven electrode.

NANOSYSTEMFABRICATIONFACILITY(NFF),HKUST
Version1.0Pa
Fig 2: Typical RIE configuration
Fig 3: Backing and turbo molecular, turbo process and turbo bypass pump down
Backing and turbo pumps: process through the turbo pump and pump down by
bypassing the turbo
With this arrangement, the chamber can be vented and roughed out without stopping
the turbo pump.
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NANOSYSTEMFABRICATIONFACILITY(NFF),HKUST
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Description of Oxford RIE 80+
Fig 3: Description of major system components for Oxford RIE 80+.
A stainless steel cabinet with removable access panels encloses the mechanical and
electronic components of the system and provides a support for the processing
chamber. Turbo molecular and rough pumps are mounted separately from the main
console cabinet.
The chamber lid and integral top electrode are raised and rotated clear of the chamber
base and substrate table by a pneumatic hoist mechanism. This provides access to the
table for loading and removal of substrates. The hoist is, for safety consideration,
operated by pressing two buttons simultaneously.
The cylindrical aluminum chamber has a view port in its upper section and three ports,
for roughing, extraction and pressure gauges, in its base. Gas is supplied to the upper
electrode “shower head” via channels in the two halves of the chamber. Moreover,
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NANOSYSTEMFABRICATIONFACILITY(NFF),HKUST
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coolant cooling is provided for the table where Reactive Ion Etching process is used.
Controls and indicators
The controls and indicators are mounted on the front of the unit as shown as below:
Fig 4: diagram of controls and indicators
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NANOSYSTEMFABRICATIONFACILITY(NFF),HKUST
Version1.0Pa
Emer
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OFF Button
Power ON LED
(
L.H.S.
)
S
y
stem ON LED
(
R.H.S.
)
Viewing port
Chamber Hoist Up/Down
Selection Switch
Chamber Hoist Buttons
Fig 5: Real picture of of controls and indicators
Chamber Hoist buttons and up/down selection switch: To raise or lower the chamber
top, the up/down selection switch is set to the required position, then both chamber
hoist buttons are pressed.
Emergency Off (EMO) button: When pressed, the system is shut down.
Power On indicator: Indicates the electrical power is connected to the machine.
System On button: Switches the system power on.
System On indicator: Indicates that the system is powered up.
System Off button: Switches the system power off.
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Emergency off and Interlock facilities
Emergency off (EMO) and interlock facilities are provided to shut down the machine
in an emergency and to stop process until the system is fully initiated. An emergency
off switch, with normally-closed contacts, is mounted on top of the console. The
switch is activated by pressing a red “Emergency Off” button.
PLC interlock chain
The interlock chain is monitored by the software, but acts independently. It is also
supplemented by machine protection sensors, which operate only via the software.
To enable RF power:
1. The 600 mbar vacuum switch (‘Vacstat’) must be at low pressure
2. The process chamber lid must be closed (or its hoist down)
3. The primary process pump must be running
4. The primary process pressure gauge (normally a capacitance manometer) must be
on scale
5. The load lock inter-chamber valve (where fitted) must be closed
6. Customer-supplied external alarm devices must be at safe state
7. The inert gas purge to the primary process pump must be flowing.
To enable process gases:
1. RF power must be enabled.
2. The gas box lid must be closed.
3. Specific gases can be set in the gas box hardware to be mutually exclusive, so
they cannot be turned on together.