F R A U N H O F E R C E N T E R F O R S I L I C O N P H O T O V O LTA I C S C S P
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1 Silicon brick sliced into solar
wafers inside a multi-wire saw.
2 3D force and torque detection
WAFERING PROCESS
ENGINEERING
system for extended wafering
process analysis .
Advanced Analysis
Expertise
of Wafering Processes
Lower your wafering costs by optimizing
Measuring, recording and analyzing of
process parameters
all performance and cost relevant data
Fraunhofer Center for
belonging to a complete wafer sawing run
Detection of
Silicon Photovoltaics CSP
paves the way for a better process under-
„„ operating forces
standing. The industrial multi-wire saws
„„ wafer quality and yield
Otto-Eissfeldt-Strasse 12
of our wafering pilot line are modified to
„„ consumption of consumables
06120 Halle (Saale) | Germany
detect forces and torques in three dimen-
Contact
sions acting on the silicon brick during the
Leads to
entire sawing process. Live acquisition and
„„ identification of critical wire loads
visualization of these data are completed
and recipe faults
Ringo Köpge
by consumption data of electrical and
„„ optimized process times
Telephone +49 345 5589 5311
cooling power and compressed air. After
„„ reduced consumptions
[email protected]
fully automatic inline cleaning processes
„„ increased wafer quality
the wafer quality and yield is determined
„„ higher wafer yield
www.csp.fraunhofer.de
by a standard industrial inspection and
sorting tool.
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Reliable Processes
Wafer Quality
Consumable Consumption
In order to run the wafering process at its
A major aspect to quantify the sawing
Cost efficiency is one of the main targets
limit of reliability the detection of forces
performance is the evaluation of wafer
in solar industry. Of particular interest is
acting on the silicon brick and the wire
geometry and topography. For each wafer
the reduction of consumables of any kind,
web helps to identify critical steps and to
relevant measures are taken automatically.
which has to be minimized to the lowest
evaluate the wire wear. By improving the
At Fraunhofer CSP the wafer thickness
possible level without impairing the wafer
slicing recipe the wafering process can be
distribution is determined as one of the
yield. This limit has to be evaluated whene-
adjusted for a higher throughput resulting
most important quality issues according to
ver consumable parameters are changed or
in a reduced cost of ownership.
industrial standards.
new products are introduced.
3 Qualitative example of mechanical loads and energy consumption of a diamond wire based wafering process.
1 Testing of cleaning compounds.
2 Total thickness variation of each
wafer out of the same sawing run.