MicroChem PriElex® SU-8 1.0 Jettable Photoresist for Inkjet-Based Direct-Write Lithography

Overview

MicroChem PriElex® SU-8 1.0 is a purpose-engineered, jettable negative-tone photoresist formulated specifically for non-contact, maskless direct-write lithography via industrial piezoelectric inkjet printing systems. Unlike conventional spin-coated SU-8 resists, PriElex® integrates rheological and interfacial properties optimized for stable droplet formation, consistent ejection, and high-fidelity deposition across heterogeneous substrates—including metals, curved surfaces, and temperature-sensitive materials. Its photopolymerization mechanism relies on cationic ring-opening polymerization initiated by UV exposure (typically 365 nm), enabling sub-10 µm feature resolution without vacuum contact or photomask alignment. The formulation eliminates solvent blending steps required in traditional SU-8 processing, significantly reducing process variability and material waste—critical for R&D prototyping, microfluidic device fabrication, and hybrid electronics integration.

Key Features

• Inkjet-Optimized Rheology: Dynamic viscosity tuned to 10–25 mPa·s at 25 °C with low shear-thinning index, ensuring reliable jetting stability across DMP-series printheads (e.g., 10–50 pL droplet volume range).
• Low-Temperature Thermal Cure: Fully crosslinked after post-exposure bake (PEB) at ≤150 °C for 30 min—compatible with polyimide, PET, and flexible PCB substrates that cannot withstand standard SU-8 hardbakes (>180 °C).
• High Optical Transparency: Minimal absorption in visible spectrum (400–700 nm), supporting optical waveguide patterning, transparent electrode encapsulation, and overlay alignment in multi-layer photonic devices.
• Enhanced Chemical Robustness: Resists etchants including buffered oxide etch (BOE), ferric chloride (FeCl₃), and ammonium persulfate—enabling use as durable etch masks for metal lift-off and deep reactive ion etching (DRIE) processes.
• Low Elastic Modulus: Engineered mechanical compliance facilitates conformal adhesion on non-planar topographies and reduces interfacial delamination during thermal cycling or mechanical bending.
• Developer Interoperability: Compatible with industry-standard aqueous alkaline developers (e.g., Microposit® MF-319, AZ® 300 MIF), eliminating need for proprietary chemistry and simplifying integration into existing cleanroom workflows.

Sample Compatibility & Compliance

PriElex® SU-8 1.0 demonstrates broad substrate compatibility—including copper, gold, silicon dioxide, silicon nitride, stainless steel, and polymeric films such as PI, PET, and PDMS. It meets ISO 14644-1 Class 5 cleanroom handling requirements when dispensed under controlled environments. While not certified to specific FDA or IEC standards, its formulation complies with RoHS Directive 2011/65/EU and REACH Annex XIV restrictions on SVHC substances. For GLP/GMP-regulated development, full lot traceability, CoA documentation, and batch-specific viscosity/solid content reports are available upon request.

Software & Data Management

PriElex® is deployed using standard Raster Image Processing (RIP) software bundled with Fujifilm Dimatix DMP platforms (e.g., DropMaster™ or third-party tools like NanoPlotter™). No proprietary firmware or closed-loop feedback modules are required. Process parameters—including droplet velocity, waveform tuning, and layer stacking sequences—are fully exportable in CSV or G-code format for audit trails and reproducibility validation. All print job metadata (timestamp, ambient RH/T, nozzle health logs) can be archived per 21 CFR Part 11-compliant electronic record systems when integrated with validated LIMS or MES infrastructure.

Applications

• Maskless fabrication of permanent 3D microstructures (e.g., microlenses, cantilevers, microfluidic channel walls) without intermediate etching or lift-off steps.
• Conformal dielectric passivation layers on irregular or high-aspect-ratio metal interconnects in power electronics and RF packaging.
• Printed insulating barriers for flexible hybrid circuits, stretchable sensors, and thin-film transistor (TFT) backplanes.
• High-resolution etch masks for Au, Cu, Ni, and Ti metallization in MEMS/NEMS fabrication where plasma-induced damage must be minimized.
• Multi-material additive patterning—co-printing with conductive inks (e.g., silver nanoparticle suspensions) to realize embedded interconnects and monolithic device architectures.

FAQ

Is PriElex® SU-8 1.0 compatible with piezoelectric inkjet printheads other than Fujifilm Dimatix?

Yes—printhead compatibility depends on fluidic interface design and waveform tuning; successful jetting has been demonstrated on Xaar 126 and Konica Minolta KM512 series with appropriate pressure and temperature control.
What is the shelf life and recommended storage condition?

Unopened bottles maintain stability for 12 months when stored at 4 °C in amber glass containers under inert atmosphere; avoid freeze-thaw cycles.
Can multiple layers be printed and aligned with sub-micron precision?

Yes—using optical fiducial markers and stage-based registration, layer-to-layer overlay accuracy of ±0.5 µm has been achieved in academic and industrial pilot lines.
Does PriElex® require post-development hardbake?

No—full crosslinking is completed during PEB; additional thermal treatment does not improve mechanical or chemical performance and may induce stress cracking.
Is there a safety data sheet (SDS) available in English and compliant with GHS?

Yes—MicroChem provides globally harmonized SDS (Rev. 2023) covering handling, disposal, and first-aid measures per OSHA HCS and EU CLP regulations.