Slot-die coating for solar cell research

Advancing solar cell research requires navigating the delicate balance between complex ink chemistries and the mechanical demands of high-precision coating. While breakthrough efficiencies are often achieved on small lab samples, maintaining that performance across larger areas presents significant technical hurdles that manual deposition methods cannot resolve.

• Uniformity over large areas: Achieving consistent thin-film thickness is critical, as even minor variations can lead to significant drops in power conversion efficiency across the device.
• Solvent sensitivity and drying control: Proper crystallization and morphology depend on precise drying profiles; poor control can cause cracking, pinholes, or deactivated surfaces.
• Material waste of costly inks: Traditional methods like spin coating often lead to high scrap rates of expensive organic solvents or lead-based precursor inks.
• Process reproducibility: Solar thin films are highly sensitive to environmental factors like humidity and temperature, requiring locked-in, recipe-controlled parameters to ensure consistent results across batches.
• Multi-layer coordination: Designing tandems or multi-junction cells involves complex interlayer engineering where each layer must be compatible with the one beneath it to maintain clean interfaces.
• Substrate and interface compatibility: Low-energy or flexible substrates can be challenging for adhesion, requiring precise gap control and surface modification to prevent beading.
• Scalability to pilot-scale: Shifting from laboratory experiments to larger pilot runs often introduces new defects if the coating window is not clearly defined and stable.

Slot-die coating offers a high-precision, pre-metered approach that directly addresses the inherent difficulties of solar thin-film research. By providing absolute control over fluid delivery and environmental parameters, it enables researchers to move beyond the limitations of manual deposition and achieve the extreme uniformity required for high-performance devices.

• Uniform thin films at scale: Unlike spin coating, slot-die deposition ensures uniform coat weight across the entire substrate, which is critical for maintaining consistent power conversion efficiency as device size increases.
• Controlled drying and crystallization: Integrated, programmable drying—such as IR or hot-air stages—allows for the precise tuning of film morphology and porosity, preventing the cracking or defects that often plague perovskite absorber layers.
• Pre-metered, waste-free processing: The closed-head design delivers the exact amount of ink required for a specific thickness, drastically reducing the waste of expensive lead-based or organic precursor inks.
• Repeatable and traceable results: Software-controlled, recipe-locked parameters ensure that every run is logged, allowing researchers to replicate successful batches across different labs and sites without performance drift.
• Engineered clean interfaces: The ability to apply precise wet gaps and optional primers ensures strong adhesion and high-quality interfaces, which are essential for the electrical performance of complex multilayer tandem cells.
• Substrate and ink versatility: Fine gap control enables uniform coatings on a wide range of surfaces, from rigid glass/ITO to low-energy, flexible polymer films, regardless of ink viscosity.
• Seamless scalability: Because the process window remains stable, recipes optimized on a small sheet-to-sheet (S2S) scale can be directly transferred to wider pilot-scale roll-to-roll (R2R) formats without reengineering the process.

We bridge research and scalable production with precise hardware, recipe-driven software, and direct support from our PhD scientists. Our systems are built for uniform, reproducible coatings on both sheet and web formats, which shortens the path from single cells to mini-modules and pilot lines.

Stability is the main hurdle. We support encapsulation trials, controlled drying, and interface tuning so device lifetime improves with every run.

Partnering with us also means you get to work with the industry’s largest in-house team of PhD-level material scientists, who share technical expertise and practical insights grounded in real-world coating applications.

We also collaborate with leading institutions to provide access to world-class training and test facilities for customer-specific workshops. These sessions provide new users with a hands-on introduction to the full scope of precise, scalable thin-film depositions for numerous applications.

Our lab scale machines

Built for fast-paced research, our lab tools create perfectly even layers with very little material waste. They are easy to set up and adjust, making them perfect for testing new materials quickly without wasting expensive inks.

These machines fit easily into gloveboxes or cleanrooms and save your protocols to ensure the same results every time, or do structured testing of different parameters. Because the process is so precise, the “recipe” you perfect in the lab is immediately ready to be scaled up for larger pre-pilot and pilot scale.

Our pre-pilot and pilot scale

Step up to wider widths and faster speeds without the typical scaling risks. By using the same slot-die heads and software as our lab tools, these platforms ensure a seamless transition from the bench to the pilot line. This continuity allows you to lock in your settings and build confidence as you scale your research from small samples to larger rolls.

Pilot scale

The FOM moduloR2R offers reliable roll-to-roll coating with precise control and customizable drying for perfect, defect-free results. You can increase your width and speed without changing your original settings. This allows you to move smoothly from testing your process to producing larger batches with total confidence.

Why it matters

• Save time with easy setup and reusable recipes.
• Get the same results every time with locked settings and history tracking.
• Scale with ease by using familiar software and protocols as you move from the lab to the pilot line.

At FOM Technologies, we are more than just an equipment provider—we are a team of scientists dedicated to your success. We host the largest team of experts in our industry to act as your true knowledge partner, helping you bridge the gap between lab-scale discoveries and pilot-scale success.

Our training and research services provide you with direct access to our leading scientists. Whether you are a new user or a veteran researcher, you will work side-by-side with our application experts to sharpen your skills, solve technical hurdles, and master the art of slot-die coating.

How our experts support your research

• Work directly with our scientists: Collaborate with our expert team to design a custom research plan that addresses your unique material challenges.
• Live, expert-led training: Every training session is a private, live-guided experience led by a FOM scientist, whether it happens online or onsite at your facility.
• Professional research services: Our scientists can execute research at the FOM laboratory on your behalf, providing you with professionally coated samples and optimized process data.
• 1-on-1 expert consultation: Use our “Book a scientist” service for direct, hourly access to our team to troubleshoot specific issues or improve your material performance.
• Hands-on technology demos: Experience a live coating process at our laboratory, guided by our experts to help you understand the full potential of slot-die technology.

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