Stensborg’s UV-Nanoimprint Lithography (UV-NIL) is a high-resolution, high-throughput patterning technique capable of replicating intricate surface features down to 20 nanometres. Developed to meet the growing demand for precision and scalability in advanced manufacturing, UV-NIL plays a critical role in fields such as optics, photonics, microfluidics, anti-reflective coatings, and functional surface engineering.
As active collaborators in publicly funded research and emerging applications projects, our specialists understand the challenges involved in adopting new nanoimprinting processes, particularly when production scalability is essential for commercial viability. Today, we explore an important early-stage development decision: selecting the right nanoimprinting resins.
Image credit: Stensborg A/S
Key terms in Stensborg’s high-performing rolling UV-NIL processes
With over 25 years of experience in nanoimprint lithography and holographic mask technology, Stensborg specialises in Roll-to-Roll (R2R) and Roll-to-Plate (R2P) nano-replication solutions. These methods facilitate the efficient patterning of rigid, flexible, and even opaque substrates, giving professionals a scalable, high-quality route to nanofabrication with minimal material waste and exceptional process reproducibility.
In any UV-NIL setup, three material types form the core of your process:
Each must be carefully selected based on compatibility, process conditions, and application-specific requirements.
Preserving the original master structure is essential in nanoimprinting. While templates have a finite lifespan, creating intermediate templates from the master ensures longevity, consistent replication quality, and process scalability. Templates act as durable, working molds, protecting the delicate master while enabling thousands of high-fidelity imprints.
Industry overview: materials, curing mechanisms, and methods
| Resin/Material Type | Curing Mechanisms | Pros | Cons | Methods |
|---|---|---|---|---|
| UV/ Light Curable | Radical | Fast curing High curing control Energy Efficiency / Cost Saving | Limited by oxygen | Roll-to-Roll and Roll-to-Plate |
| UV/ Light Curable | Cationic/ Anionic | High curing control Less sensitive to ambient air Energy Efficiency / Cost Saving | Limited by humidity Slower curing Restricted compatibility | Roll-to-Roll and Roll-to-Plate |
| Thermoset (Heat) | Radical, Cationic & other | Broad material selection | Time consuming Requires heat | Lamination and Plate-to-Plate |
| Thermoplastics | Temperature | Broad applications Established technology | Shrinkage prone High energy-consuming | Injection Moulding and Hot Embossing |
At Stensborg, we primarily focus on UV-curable resins due to their ability to deliver room-temperature processing, outstanding resolution, and high-throughput replication.
Thanks to our in-house R&D chemistry labs and more than 20 years of formulation experience, we can address common resin challenges, such as oxygen inhibition and material compatibility, through tailored solutions.
Selecting the most suitable Template Resin
Choosing the right template resin impacts template durability, replication fidelity, and the ease of demoulding, all critical factors for both small batch R&D projects and industrial level productions.
Key considerations include:
1. Material Compatibility
Good adhesion to polycarbonate (PC), PET, or other chosen substrates, possibly with adhesion promoters if necessary.
2. Master Safety
Must not chemically react with or damage the master.
3. Feature Size and Viscosity
Typically, smaller features require lower viscosity resins to ensure full cavity filling.
4. UV Transparency
The template substrate and template material should be transparent if you want to use roll-to-roll or roll-to-plate setups in order not to block the UV light from curing.
| Features | Viscosity | Resins for Template | Project Scale |
|---|---|---|---|
| Large (>500nm) | Medium (850 mPa*s) | DM57 | Good for prototyping and experimenting with process designs |
| Small (<3μm) | Low (50 mPa*s) | Currently in development | Good for prototyping and experimenting with process designs |
Stensborg has 20+ years of experience formulating specialty template chemistry, and provides custom solutions for your projects, particularly valuable when you plan to upscale your production.
Selecting your process Replica Resin
Matching resin viscosity to feature size is crucial. To ensure high-quality nano or microstructure replication, the resin must fill the mould cavities without trapping air. Generally, structures larger than 1 micron require medium-to-low viscosity resins, while submicron structures require very low viscosity materials.
| Features | Viscosity | Resins for Replica | Process Compatibility |
|---|---|---|---|
| Large (>1μm) | Medium to low (300 mPa*s) | X29 | Spin coating, Flexoprinting |
| Small (<1μm) | Low (20 mPa*s) | X30 | Inkjet system |
Application-specific properties to consider when designing your nanoimprinting process:
Tailoring your resin and processing setup to your intended application is vital for achieving optimal results, for instance, if you need a final flexible surface or have unique adhesion requirements to consider when designing your development. From experience, here are some application-specific considerations when designing an efficient nanoreplication production with UV nanoimprint lithography:
Additionally, adhesion to your selected substrate, whether PET, PC, or specialised materials, is a critical validation checkpoint that Stensborg’s specialists routinely assist with during project setup.
How to Successfully Begin Your Development Process
Bringing a nanoimprint project from concept to volume production is a multi-stage journey. From our varied client experience, all developments are unique and highly dependent on the level of proof of design, requirements, and experience of the professionals involved.
Nevertheless, a phased approach typically proves most effective for newcomers to UV-NIL, helping to minimise risks, accelerate time-to-market, and manage development costs.
Step 1: Proof of Concept
The goal at this stage is to rapidly validate the feasibility of replicating your desired nanostructures or micro-optical features using UV-NIL.
We recommend using our compact Desktop R2P NanoImprinter alongside our proprietary UV-curable resins for an agile and customisable testing experience.
This high-speed setup allows for systematic fine-tuning of key imprinting parameters (rolling speed, applied pressure, and UV exposure) to achieve the target resolution, defect-free replication, and reliable demoulding behaviour without damage to the template or substrate.
Step 2: Fine-tuning and implementation
In this stage, the resin chemistry, process parameters, and mechanical settings (force, light intensity, speed) are further optimised to meet final product specifications. Whether your target is a specific refractive index for optical applications, enhanced biocompatibility for microfluidic devices, or long-term UV stability for coatings, Stensborg provides hands-on technical support, drawing on hands-on knowledge from collaborative development projects in nano-optics and scalable nanofabrication.
Step 3: Volume production
Finally, when your process is fully optimised, Stensborg partners with your engineering and manufacturing teams to design and deliver custom-built industrial nanoimprint machinery, tailored to your substrate type, feature sizes, throughput demands, and overall production environment.
Whether you require roll-to-roll continuous nanoimprinting for flexible electronics or roll-to-plate systems for rigid substrates in photonics, our custom solutions are built to ensure precision, reliability, and scalability for large-volume manufacturing of nano- and microstructured surfaces.
