PRiMELiNE - Roth & Rau AG

PRiMELiNE CdTe
Cadmium Telluride Fab - Cluster Tools for
Thin Film SolarModule Manufacturing

PRiMELiNE
Turnkey Solutions by Roth & Rau
Under the brand name PRiMELiNE Roth & Rau offers PV turnkey
lines assuring a successful implementation of a state of the art
production facility. Now, Roth & Rau CTF Solar is the first company
worldwide to offer turnkey solutions for the production of Thin
Film PV Modules, based on the reliable CdTe-technology.
The advantages of the Roth & Rau turnkey offering are obvious:
The “One-stop-shopping” solution has been designed for customers
wanting to focus on their core business and wanting to
rely on a strong partner with a proven track record of successfully
realized turnkey projects worldwide.
With a PRiMELiNE CdTe Turnkey Line Roth & Rau delivers state-ofthe-art
and future proof technology, based on a continuous improvement
of all components of the turnkey line, their integration,
and accurate process design. To keep track with the continuous
development in high technology, Roth & Rau maintains a broad
network with renowned Research & Development partners.
Roth & Rau is proud of its international appreciation as technologically
leading company based on its strong commitment to
R&D. Our continuous equipment improvement ensures a long lifetime
of our PRiMELiNE CdTe product. The focal points in all development
activities of the PRiMELiNE CdTe turnkey line are: Environmental
responsibility, superior Cost of Ownership (CoO) and technological
leadership. One of the outcomes of these principles is
the design of the PRiMELiNE CdTe following the “Emission-free fab”
concept, allowing operation of the production line with emissions
close to zero.
For customers that already invested into a CdTe Thin Film factory or
who wish to integrate own or local content, Roth & Rau CTF Solar
offers cost efficient, proven processing tool clusters that can be
seamlessly integrated into either new production lines as well as
into existing lines. The sum of all fully integrated clusters is the
innovative yet proven PRiMELiNE CdTe Turnkey production line. The
turnkey clusters are designed to provide specific process knowledge
combined with suitable process equipment and processing
material specification, project management and equipment startup
for highest process reliability and product quality. All
PRiMELiNE CdTe Clusters are capable of processing module sizes
of up to 1200 x 1600 mm, with a throughput of up to 70 modules
per hour. The table below provides to you an overview on our
PRiMELiNE CdTe 80 MW Turnkey line offering and our PRiME-
LiNE CdTe Turnkey clusters.

PRiMELiNE CdTe Laser Cluster (80 MW)
CdTe Thin Film PV Modules have been recognized as the markets
most cost efficient solution for PV applications. To support cost
efficient, proven processing, Roth & Rau CTF Solar offers processing
clusters and tools for all thin film PV module customers
worldwide that can be seamlessly integrated into new production
lines as well as into existing fabrication lines. The Roth & Rau CTF
Solar chosen cluster design provides to the customer specific
process knowledge combined with suitable process equipment
and processing materials, project management and equipment
startup in order to enhance product quality and module efficiencies.
All PRiMELiNE CdTe Clusters are capable of processing standard
module sizes of 1200 x 1600 mm (other dimensions on
request), with a throughput of > 60 modules per hour. Basis for the
design of all PRiMELiNE CdTe Cluster Tools is the innovative yet
proven PRiMELiNE CdTe Turnkey production line.
The PRiMELiNE CdTe Laser Cluster contains three Laser Scribers
for P1, P2, P3 cuts and a Laser Edge Deletion tool. Equipment
selection is optimized for use on CdTe. Although the individual
tools of the Laser Tool cluster are spread inside the sequential
tool layout of a thin film production line, customers can benefit
from this tool package as all tools are matched with respect to
performance and specification for optimized utilization of active
module surface area.
Thin film PV modules require several special processing steps in
order to generate a pattern of multiple PV sub cells that needs to
be very precise, as well as a fast and reliable layer removal without
damaging the substrate itself for preparation of the backend
edge sealing process. Therefore the application of laserbased
tools is just a logical consequence, as laser tools are known as
precise and powerful machining tools.
Laser Scribers for P1, P2, P3 cuts
These laser systems are used for scribing of the thin-films of conductive
and semi-conductive materials on large substrates to produce
stripes of defined width parallel to the substrate´s long or
short edge depending on the modules' cell orientation. The position
of each P1, P2, and P3 scribe is shifted by a small distance in
order to connect all sub cells serially to each other. To guarantee
for minimal distances between P1 and P2 resp. P3 cuts both P2
and P3 laser use a dynamic line tracking mechanism; this feature
provides for optimized active cell areas and - in total - for high
module efficiencies. The number and width of the individual sub
cells are optimized for a maximum utilization of active module surface.
The Scribing tools are programmable; to achieve sufficient
throughput each Scribing tool is equipped with several pulsed
lasers, and each laser beam is split into several cutting beams.
In accordance with the layer composition each tool's laser
wavelength is adapted; used laser wavelengths are 532 nm resp.
1064 nm. Damage of underlying layers is avoided, which is of special
importance for P2 and P3 cuts: Both cuts are not allowed to
cut into the underlying TCO layer. All laser tools use a dynamic,
active focusing for excellent scribing process
Key features:
Throughput > 60 substrates/h
Module size up to 1200 x 1600 mm
Scribing line width 35 - 70 m,
Line-to-line distance 5 - 15 mm
(adjustable per software setting)
Multiple processing beams, depending
on specific requirements
Air bearings to guide laser axis‘
Massive granite processing table
for optimum accuracy
Dynamic focusing (optional)
Dynamic line tracking (optional)
Integrated laser fumes exhaust
and filtration system
Integrated P1 and P2 input substrate cooling

PRiMELiNE
Turnkey Solutions by Roth & Rau
Laser Edge Deletion tool
The Edge Ablation Machine removes all deposited layers around
the substrate with a programmable width on the substrate front
side and - additionally - around its outer edges. Precision, high
process speed and stability, and a residue-free processing are
key for this machine.
Key features:
Nd-YAG high-energy laser with scanner
Laser wavelength 1030 - 1060 nm
Programmable ablation widths in steps
between 2 - 30 mm width
Optional dynamic focusing
Process integrated quality inspection
Integrated laser fumes exhaust system
All Laser tools are designed to comply with the Roth & Rau CTF
Solar principle of delivering only environmental friendly tools, as
also realized in the entire PRiMELiNE CdTe turnkey production line,
which is designed to keep the "environmental footprint" as small
as possible:
All fab emissions are post-treated already at tool-level so that virtually
no contaminated or hazardous substances can be released
to the environment, and used processing fluids are recycled for
minimal consumption values
Turnkey Cluster
PRiMELiNE CdTe Laser Cluster (80 MW)
Project duration
Cluster content
12 months
– Optimization of Scribing Pattern
– Laser Scribing 1
– Laser Scribing 2
– Laser Scribing 3
– Scribing Quality Monitoring Each
– Substrate Temperature Control for Scribing 1 to 3
– Automated focus control
– Dynamic Scribing Distance Control for Scribing 2 and 3
– Laser Edge Deletion
– Exhaust Air Filtration Safety Housings
– Other relevant EHS Provisions

PRiMELiNE CdTe Coating Cluster (80 MW)
CdTe Thin Film PV Modules have been recognized as the markets
most cost efficient solution for PV applications. To support cost
efficient, proven processing, Roth & Rau CTF Solar offers processing
clusters and tools for all CdTe customers worldwide that
can be seamlessly integrated into new production lines as well
as into existing fabrication lines. The Roth & Rau CTF Solar chosen
cluster design provides to the customer specific process
knowledge combined with suitable process equipment and processing
materials, project management and equipment startup
in order to enhance product quality and module efficiencies.
All PRiMELiNE CdTe Clusters are capable of processing standard
module sizes of 1200 x 1600 mm (other dimensions on request),
with a throughput of > 60 modules per hour. Basis for the design
of all PRiMELiNE CdTe Cluster Tools is the innovative yet proven
PRiMELiNE CdTe Turnkey production line.
The key process in manufacturing of CdTe PV modules is the deposition
of the photo-active CdS (Cadmium Sulfide) and CdTe
(Cadmium Telluride) layers onto the substrate. Module efficiency
is mainly predetermined in these critical process steps. The
Roth & Rau CTF Solar CSS (Closed Space Sublimation) Deposition
Tool is a vacuum-based tool that incorporates many years of field
proven deposition technology: Based on commercial scale coating
equipment using this deposition technology CdTe cells of
12,7% efficiency have been achieved.
In the current generation of the CSS Tool many enhancements
and design optimizations have been implemented, therefore deposition
rates, film thickness uniformities, film qualities and tool
reliability are among the highest within the market. The deposition
process originally developed at the Batelle institute and producing
the world-record CdTe cell efficiency, is performed in a vacuum
atmosphere and at high temperatures (> 500 °C). The substrates
are fed into the CSS Deposition Tool as a substrate band,
transport speed is continuous at about 1.5 m/min. The layers are
deposited at the bottom surface of the substrates by nucleation of
CdS respectively CdTe vapours on the substrate surface. Due to
its unique technology the current Roth & Rau CTF Solar deposition
process is the far cleanest CdS / CdTe deposition technology
available worldwide. Included in the CSS Deposition tool is an
integrated cooling section that carefully cools the substrates to
ambient temperature without introducing thermal stress and
therefore contributing to long module lifetimes.
Typical film thicknesses are 30 - 100 nm CdS, and 2 - 5 m CdTe.
A major feature of the CSS deposition technology is - unlike films
deposited with non-vacuum conditions - the formation of dense,
non-porous films. Raw materials are utilized with > 95%, contributing
to the low CoO of the CSS Deposition Tool. It operates
fully automatic, it is programmable to achieve best process
results on various types of substrates.
The deposition zone is contained by a special exhausted and
filtered enclosure; hazardous materials are handled exclusively
within this enclosure, additionally the entire tool is contained
in a second enclosure, providing for an EHS-proof design. This
feature adds to the Roth & Rau CTF Solar principle of delivering
only environmental friendly tools, as also realized in the entire
PRiMELiNE CdTe turnkey production line, which is designed to keep
the "environmental footprint" as small as possible: All fab emissions
are post-treated already at tool-level so that virtually no
contaminated or hazardous substances can be released to the
environment, and used processing fluids are recycled for minimal
consumption values.
Key features:
Short substrate edge leading
Cycle time < 60 s
Deposition temperature app. 600°C
Integrated exhaust filtration
Integrated heating and cooling zones
Vacuum pumps
Deposition zone for sequential deposition
of both CdS and CdTe
Low fab facility requirements
Double enclosure design providing for
high ESH standards.

PRiMELiNE CdTe Activation Cluster (80 MW)
CdTe Thin Film PV Modules have been recognized as the markets
most cost efficient solution for PV applications. Various CdTe deposition
processes have been established, whereas the basic processing
around the CdS / CdTe layering is rather similar in all
CdTe production lines. To support cost efficient, proven processing
Roth & Rau CTF Solar offers processing clusters for all CdTe
customers worldwide that can be seamlessly integrated into
new production lines as well as into existing fabrication lines. The
Roth & Rau CTF Solar chosen cluster design provides to the customer
specific process knowledge combined with suitable
process equipment and processing materials, project management
and equipment startup in order to enhance product quality
and module efficiencies. All PRiMELiNE CdTe Clusters are capable
of processing standard module sizes of 1200 x 1600 mm (other
dimensions on request), with a throughput of > 60 modules per
hour. Basis for the design of all PRiMELiNE CdTe Cluster Tools is the
innovative yet proven PRiMELiNE CdTe Turnkey production line. The
Roth & Rau CTF Solar principle of delivering only environmental
friendly tools, as realized in the entire PRiMELiNE CdTe turnkey production
line, which is designed to keep the "environmental footprint"
as small as possible, applies also to the
For a seamless integration into existing production lines the
PRiMELiNE CdTe Activation Cluster uses a standardized SECS/GEM
protocol, substrate-ID-tracking (virtual / DMC reader), and adaptable
horizontal communication with adjacent process tools.
Nevertheless, the cluster can be operated also fully autonomous,
with recipe administration on Cluster level.
In detail, the PRiMELiNE CdTe Activation Cluster consists of a Coating
Machine, an Activation Furnace, and a Cascade Washing/Cascade
Rinsing tool.
Roth & Rau Activation Cluster
All fab emissions are post-treated already at tool-level so that virtually
no contaminated or hazardous substances can be released
to the environment. Also, the entire Cluster is enclosed with a
safety housing to contain all hazardous substances and to avoid
any contamination of the remaining production environment. A very
critical step in processing of CdTe PV-modules is the activation of
the CdS / CdTe layer stack with its target to improve the physical as
well as electro-optical properties of the CdS / CdTe stack. Here, as
also applied by leading CdTe solar module producers, a dedicated
CdCl 2 activation, combining a CdCl 2 deposition plus a subsequent
heat treatment, is used. The Roth & Rau CTF Solar processing solution
provides all necessary tools plus appropriate, perfectly harmonized
materials and process selection for a cost efficient activation
and enhanced module efficiency.
Therefore the Roth & Rau CTF Solar Activation Cluster can be a reliable
retrofit for tools in existing production lines while adding
improved module performance for shorter payback times of investments.
However, together with the Roth & Rau CSS type of CdS /
CdTe films and its characteristic properties the Activation Cluster
tool offers a perfectly harmonized chemical activation process.
Coating Machine
During fully automatic processing within the coating tool an
aqueous film containing dissolved CdCl 2 is applied in a defined
thickness on the surface of the glass pane utilizing a specially
engineered roller-coating system. Adding a specially formulated
mixture to the coating solution allows for an excellent
uniformity of the liquid film over the entire surface by improving
the specific wetting characteristics. The preparation of the
coating solution is done in a dedicated chemical cabinet next to
the core process modules of the tool taking care of the specific
handling precautions of the used materials. After successfully
depositing the solution onto the substrate a drying step safely
removes all liquid remnants while the CdCl 2 remains on top of
the CdTe layer. As part of the Roth & Rau CTF Solar Activation
Cluster all necessary peripherals to prevent the release of hazardous
liquids and gases are included. A closed loop DI water
supply is available as an option to account for low operating
costs and low factory facility requirements.

PRiMELiNE
Turnkey Solutions by Roth & Rau
Key features:
Short substrate edge leading
Layer stack facing upwards
Cycle time < 60 s
Integrated substrate heating
Selectable composition of CdCl 2 -solution
Closed-loop waste water reconditioning
Integrated exhaust filtration
Safety housing
Automatic cleaning routines for
easy maintenance..
Cascade Washing/ Cascade Rinsing tool
After deposition and tempering of the CdCl 2 layer all remaining
residues are removed in a cleaning step so that the substrates
can be processed in subsequent process steps without any
risk of CdCl 2 contamination to tools and operators. The cascade
washing machine is the final tool within performing the activation
process.
DI-water is applied stepwise on all substrate surfaces utilizing
the eponymous "cascade"-setup of cleaning modules. The procedure
is performed without adding any chemical additives to the
rinse water. After removal of the CdCl 2 layer the substrates are
automatically transferred to an integrated drying section where
liquid film is evaporated. All used DI-water is collected and recycled
on tool level.
Activation Furnace
In close combination with the coating tool the activation furnace
supports the restructuring of the CdS / CdTe layer stack.
After CdCl 2 coating the substrate enters the furnace where
the glass pane is heated up to a defined and well controlled
activation temperature.
Temperature and transport speed are adjustable. Subsequent
to the tempering process the substrate is cooled down carefully
in order to avoid that thermal stress remains inside the
glass. All mentioned steps are performed under standard
atmospheric conditions.
Key features:
Long substrate edge leading
Layer stack facing upwards
Cycle time < 60 s
Atmospheric process
Activation temperature @ app. 400 °C
Activation time adjustable between 10 - 20 min
Integrated cooling tunnel
Integrated filtration of exhaust gases - no special
contaminated exhaust duct system necessary
Safety housing

PRiMELiNE
Turnkey Solutions by Roth & Rau
Key features:
Short substrate edge leading
Chemical layer facing upwards
Cycle times < 60 s
Integrated recycling of used rinsing DI water
No chemical additives needed
Integrated dryer
Safety housing
Turnkey Cluster
PRiMELiNE CdTe Coating Cluster plus
PRiMELiNE CdTe Activation Cluster (80 MW)
Project duration
14 months
Cluster content
Coating Cluster
– CdS/CdTe Coating (CSS)
– Substrate Cooling Section
– Vacuum System
– Closed Loop Water cooling System
– Safety Housings
Activation Cluster
– Conveyor
– Conveyor EX, Conveyor EX SEL, Conveyor EX SEL Inspection,
Conveyor EX LEL, Conveyor LEL, Conveyor SEL,
Conveyor SEL Inspection
– Activation Coating Unit
– Rotary Table EX
– Corner Transfer EX
– Activation Furnace
– Corner Transfer
– Rotary Table
– Cascade Rinsing + Closed Loop DI Water Regeneration
– Safety Housings
– Relevant EHS provisions
– EHS Equipment

PRiMELiNE CdTe Back-Contact Cluster (80 MW)
CdTe Thin Film PV Modules have been recognized as the markets
most cost efficient solution for PV applications. To support cost
efficient, proven processing Roth & Rau CTF Solar offers processing
clusters and tools for all CdTe customers worldwide that
can be seamlessly integrated into new production lines as well as
into existing fabrication lines. The Roth & Rau CTF Solar chosen
cluster design provides to the customer specific process knowledge
combined with suitable process equipment and processing
materials, project management and equipment startup in
order to enhance product quality and module efficiencies. All
PRiMELiNE CdTe Clusters are capable of processing standard module
sizes of 1200 x 1600 mm (other dimensions on request), with
a throughput of up to 70 modules per hour. Basis for the design
of all PRiMELiNE CdTe Cluster Tools is the innovative yet proven
PRiMELiNE CdTe Turnkey production line.
A major process in manufacturing of CdTe PV modules is the formation
of the back contact which allows for efficient collection of
generated PV current. The Roth & Rau CTF Solar Back Contact
cluster can be retrofitted for tools in existing production lines
while adding improved module performance for shorter payback
times of investments.
In order to achieve high CdTe PV Module energy efficiencies,
a low resistance back contact needs to be integrated into the
CdTe Solar Module. This process step requires state-of-the-art
know-how of CdTe surface preparation, back contact material
selection, deposition technology, and equipment design to
integrate the metallic back contact in the design of the CdTe PV
module. In consequence, all sub-processes within this cluster
are carefully adapted to each other and individually optimized
with regard to etching rate, layer sequence, layer thickness,
process homogeneity.
The Roth & Rau CTF Solar Back-Contact processing provides for
one of the lowest available film resistivity that enables high solar
module energy efficiencies, high fill factor, long term stability, and
compatibility with subsequent backend processes such as bus
bar application and lamination.
For a seamless integration into existing production lines the
PRiMELiNE CdTe Back Contact Cluster uses a standardized SECS/
GEM protocol, substrate-ID-tracking (virtual / DMC reader), and
adaptable horizontal communication with adjacent process tools.
Nevertheless, the cluster can be operated also fully autonomous,
with recipe administration on Cluster level. All sub-processes are
decoupled by a substrat buffer stations which allow for scheduled
maintenance of single tools without interruption of production of
other cluster tools. This provides for a high cluster uptime and a
flexible maintenance planning.
In detail, the PRiMELiNE CdTe Back Contact Cluster consists of a
CdTe Surface Preparation tool and a Metal Contact Deposition tool.
CdTe Surface Preparation Tool
The surface preparation consists of an etching step to prepare
the CdS / CdTe layer stack before it is fed into the metal deposition
equipment. The target of the preparation process is to establish
a p+-doped layer of defined thickness on top of the CdTe
surface by removing the existing Cd while simultaneously enrichening
Te by a special etching process. Any liquid residues are
removed by subsequent rinsing of the substrate with DI water.
Set up of the etching solution is done in a chemical cabinet located
next to the core process modules of the machine. Drained
etching solution is collected and treated in a waste water subsystem.
Traces of hazardous gases that may be generated during
processing of the substrate are safely exhausted to a customized
filtration unit.
Key features:
Short substrate edge leading
Chemical layer facing upwards
Cycle time < 60 s
Selectable composition of etchingsolution
Actively controlled etching rate and composition
of etching solution with automatic compensation
for selective consumption of components
Integrated substrate rinsing and drying, integrated
exhaust filtration
Optionally available with a closed loop for flushing
DI-water - no external DI-water supply required
No release of contaminated waste water

PRiMELiNE
Turnkey Solutions by Roth & Rau
Metal Contact Deposition tool
After chemical preparation the substrates are automatically
transferred into the metal contact deposition tool. The back contact
processing is accomplished with a dedicated PVD process,
within this process several metal materials can be sputtered onto
the CdS / CdTe layer stack in order to optimize sheet resistance of
the sputtered layers. Sputtered layer composition and processing
conditions may be optimized depending on customer requirements.
The metal contact deposition tool is explicitly designed for exceptional
high production performance with long uninterrupted
sputtering times and a synchronized sputter target lifetime
with optimized preventive maintenance intervals to achieve high
tool uptime.
Key features:
Short substrate edge leading,
layer stack facing upwards
Cycle time < 60 sec.
Long uninterrupted sputter campaigns
High process stability and accuracy
High yield, high reliability, high availability
Maintenance friendly
Vacuum pumps included
Integrated substrate heating for hot sputtering
Integrated filtration of exhaust gases
Integrated cooling zone
All Back Contact Deposition tools are designed to comply with the
Roth & Rau CTF Solar principle of delivering only environmental
friendly tools, as also realized in the entire PRiMELiNE CdTe turnkey
production line, which is designed to keep the "environmental
footprint" as small as possible: All fab emissions are post-treated
already at tool-level so that virtually no contaminated or hazardous
substances can be released to the environment, and used
processing fluids are recycled for minimal consumption values.
Turnkey Cluster
PRiMELiNE CdTe Back-Contact Cluster (80 MW)
Project duration
Cluster content
13 months
– Etching station with closed loop DI-water
supply and wastewater treatment
– 2 conveyors
– Buffer station incl. 3 storage boxes
– Back-contact magnetron sputtering machine
– Substrate cooling section
– EHS equipment

PRiMELiNE CdTe Back-End Cluster (80 MW)
CdTe Thin Film PV Modules have been recognized as the markets
most cost efficient solution for PV applications. To support cost
efficient and proven processing Roth & Rau CTF Solar offers processing
clusters and tools for all thinfilm PV customers worldwide
that can be seamlessly integrated into new production lines as
well as into existing fabrication lines. The Roth & Rau CTF Solar
chosen cluster design provides to the customer specific process
knowledge combined with suitable process equipment and
processing materials, project management and equipment startup
in order to enhance product quality and module efficiencies.
All PRiMELiNE CdTe Clusters are capable of processing standard
module sizes of 1200 x 1600 mm (other dimensions on request),
with a throughput of > 60 modules per hour. Basis for the design
of all PRiMELiNE CdTe Cluster Tools is the innovative yet proven
PRiMELiNE CdTe Turnkey production line.
The backend processing of PV modules is crucial for achieving
high module reliability and lifetime. Especially module certification
acc. to DIN EN 61464 and DIN-EN 61740-1/2 is highly
dependent on the overall quality of the Back-End process. The
Roth & Rau CTF Solar Back-End Cluster provides for a well engineered
total solution, including material selection, process know
how, and equipment specification and therefore ensures for a
"glitch-free" product certification and PV module lifetimes > 20
years. The PRiMELiNE CdTe Backend Cluster is specifically designed
for CdTe photovoltaic modules. To provide for a balanced
investment cost optimization a mix of automatic and manual processes
is chosen.
The Roth & Rau CTF Solar Back-End Cluster comprises a complex
sequence of module processing tools: Module test, busbar application,
edge sealing, marriage (e.g. application of encapsulant foil
plus layering of backside glass), lamination, junction box application,
and final testing (flasher, wet leakage, and metrology) plus
labeling. An optimized, integrated substrate buffering concept
(buffer station with exchangeable storage boxes, FILO buffers,
loading stations) is integrated into the cluster design which
allows for flexible maintenance schedules and reduced impact of
unscheduled equipment events. Of course all intermediate substrate
transport devices necessary for operation of the entire
Back-End are included in the Cluster design.
For a seamless integration into existing production lines the
Roth & Rau CTF Solar Back-End Cluster uses a standardized
SECS/GEM protocol, substrate-ID-tracking (virtual / DMC reader),
and adaptable horizontal communication with adjacent process
tools.
The Module Tester yields a Go/No Go decision and determines if
the module is worth applying the backend process. This is accomplished
by an automatic I-V-curve tracing when applying light to
the module and allows for a calculation of most electrical key
parameters ( Isc, V0C, Pmax, FF, Rserieal, Rparallel). The Module
Tester uses state-of-the-art LED lighting which allows for long
uptimes and reliable functionality.
In the Busbar Application machine the module's sub cells are
connected via a conductive, low-loss Cu-ribbon and a conductive
silver paste. Alternatively soldering or ultrasonic welding
methods can be used, depending on the specific physical properties
of the photovoltaic layers. All components in this process are
carefully selected with special attention to long-term reliability
of the module.
The Edges Sealing tool applies an UV-stable and highly resistive
string of sealant, variable in width and thickness, in an extrusion
process. Other than in available Back-End processes this special
process serves as an additional barrier against humidity penetrating
into the module and is therefore part of the "dual component"
sealing solution. Roth & Rau CTF Solar delivers to its customers
an optimized and tested combination from equipment, material,
and application process for an unsurpassed module lifetime.

PRiMELiNE
Turnkey Solutions by Roth & Rau
After mounting of busbars and application of edge sealant
the processed substrate, the washed and cleaned back glass,
and the encapsulant foil are mounted together to a stacked sandwich.
This fully automated process tool is called "marriage".
The marriage station is designed to process glass and encapsulant
foil for module sizes up to 1200 x 1600 mm; encapsulant foil
material may be EVA or PVB, which is fed to the machine from
rolls and then cut to the appropriate size and precisely placed
onto the substrate. Encapsulant foil size and positioning with
respect to the edge sealant "frame" is essential for a good subsequent
lamination process result.
The Laminator forms a mechanical stable module from the glassfoil-glass
stack created in the process before, that can withstand
all environmental effects that a PV module is exposed to. This is
accomplished by applying heat and pressure to the stack for a
defined time. Temperatures are adjustable and precisely controllable,
depending on the encapsulant foil material. Pressure is
adjusted in order to obtain a bubble-free, homogenously polymerized
encapsulant material. Included in the scope of delivery is the
integrated cooling press to cool down the modules to temperatures
that allow safe subsequent processing.
After lamination the PV module is almost ready, only the specially
adapted junction box needs to be connected to the busbar on the
module backside. This process step can be executed either manually
or fully automatic, with crimp or soldering connection to the
busbar, with adhesive pads, hot melts or silicone adhesives, with
metal or polymer junction boxes: Obviously, all customer requirements
can be fully met by the flexible process station design.
Final testing consists of a Flasher, a Wet Leakage Tester, and a
Visual Inspection Station. Flashing simulates PV module output at
sunlike illumination (STC, 1000 W/m 2 , AM 1.5 global) and therefore
enables determination of module output parameters Pmax, Impp,
Umpp, Isc, Uoc, and - finally - the module efficiency . Design of the
Flasher may be either horizontally or vertically, depending on the
individual requirements at customer's site.
A Wet Leakage Test (= High Potential Test) ensures proper electrical
insulation of the module. UL1703 and IEC61730 are the basic
standards, covering requirements for safety and construction of
photovoltaic modules to address prevention of electrical shock
and fire hazards. These two base standards are to be used in conjunction
with IEC61646. Only modules that pass this test are
considered as "sellable modules" and will be labeled according
to its output power. Label printer and software connection to
Flasher and Wet Leakage tester is included in the Backend Cluster
design. Metrology tools utilized within the Roth & Rau CTF Solar
Back-End Cluster comprise of a back glass inspection (broken
corners, chipping, and edge cracks) and a module inspection
(lamination bubbles, lamination inclusions, glass breakage). All
inspections are fully automatic, incorporating image recognition
and analysis. Optionally, additional inspection methods (electro
luminescence, photo luminescence) can be integrated in the
Back-End Cluster layout.
Key features:
Cluster output > 60 substrates / h
Integrated substrate transport system
Short substrate edge leading
Integrated inspection and metrology (adaptable)
Flexible process design (adaptable to various
encapsulant foil materials
Junction box designs, process/throughput
requirements at lamination
Flasher mechanical design),
Xenon lamp flashing
Automatic module labeling
Flexible and adaptable MES connection
Integrated cooling press at the laminator
All Back-End tools are designed to comply with the Roth & Rau
CTF Solar principle of delivering only environmental friendly tools,
as also realized in the entire PRiMELiNE CdTe Turnkey production
line, which is designed to keep the "environmental footprint" as
small as possible: All fab emissions are post-treated already at
tool-level so that virtually no contaminated or hazardous substances
can be released to the environment, and used processing
fluids are recycled for minimal consumption values.

Turnkey Cluster
PRiMELiNE CdTe Back-End Cluster (80 MW)
Project duration
Cluster content
13 months
– 2 Buffer Stations
– Bus bar application
– All necessary substrate transport
(14 conveyor SEL, 6 conveyor EX SEL, rotary table)
– Edge sealing (butyl)
– 2 FILO buffer 30 subs
– Back glass washer plus closed loop wastewater treatment
– Back glass loading station
– Back glass inspections
– Corner transfer
– Buffer station incl. 3 storage boxes
– Marriage station + foil loader + slicing
– Lamination loading
(10 corner transfers, 7 conveyor LEL, 2 rotary tables)
– Laminators (including cooling press)
– Lamination unloading (portal crane)
– FILO buffer 50 subs
– Automated lamination quality inspection
– Manual junction box mounting station
– High potential test
– Flash tester
– Labeling
– Unloading station for finished modules
– EHS equipment

PRiMELiNE
Turnkey Solutions by Roth & Rau
Turnkey Cluster
PRiMELiNE CdTe Automation and Metrology Cluster (80 MW) and MES
Project duration
Cluster content
14 months
– Substrate Marking
– Substrate Tracking System
– Substrate Transport System
– Substrate-Inspection
– x Buffer Substrate Stations
– Buffer- & Transport Boxes for 1.400 plus substrates
– Cooling sections
– Heating sections
– PV Function Check
– MES and Line integration services
Turnkey Cluster
PRiMELiNE CdTe Ramp-Up Cluster
Project duration
9 months
Cluster content
– Shipping
– Data pack for building permit
– EHS data pack
– Move-in/ Move-in Project Management
– Turnkey Project Management
– Full service Ramp-up
– Staff training
– EHS Consulting
– Material Management Consulting
– Raw Materials and Component Specification
– Staff training (“classroom” and “on the job”)
– Total Annual Output and Efficiency Warranty
Turnkey Cluster
Total PRiMELiNE CdTe Cluster + Service /
Complete Turnkey Line 80 MW
Project duration
24 months

PRiMELiNE CdTe - Turnkey solutions by Roth & Rau
Turnkey solution features
All equipment from one hand
Developing new generations of turnkey solutions
The best developed sales and service network
in photovoltaics worldwide
Roth & Rau CTF Solar is the first supplier of
complete production lines and cluster tools
for cadmium-telluride thin film solar modules
Our Scope
Customer‘s Benefits
Integrated equipment, technology and service package
Factory layout assistance
Equipment installation and start-up procedure
Technology transfer and production
Ramp-up support
Training of the staff
After sales service and support in spare part logistics
Quick mass production launch
High technology level
Low running cost
High marketing acceptance for the product
(20% market share in world PV market)
Esthetical appearance
Very good performances at diffuse sunlight
and high temperatures
High marketing acceptance for the product (20% market share in world PV market)
Esthetical appearance
Very good performances at diffuse sunlight and high temperatures

Roth & Rau CTF Solar GmbH
An der Baumschule 6-8
09337 Hohenstein-Ernstthal
Germany
Phone +49 3723 66 85 0
Fax +49 3723 66 85 100
E-mail info@roth-rau.com
www.roth-rau.com