An illustration of the DPN process.

What is DPN®?

Dip Pen Nanolithography® (DPN®) is a direct write, tip based lithography technique capable of multi-component deposition of a wide range of materials with nanoscale registry. DPN can fabricate multiplexed, customized patterns with feature sizes as small as 50 nm or as big as 10 µm on a variety of substrates including glass, plastic, gold and silicon.  Using arrays of “pen” tips, these features can be printed over large areas, with pattern design and fabrication often taking less than an hour to complete. DPN is a powerful yet simple-to-use benchtop technology that delivers direct write patterning capabilities without the need for a cleanroom, master stamp or photomask. 

With the ability to operate under ambient conditions and deposit features with sub-cellular resolution, DPN can successfully print organic, inorganic, and biological materials (including proteins, nucleic acids, lipids, hydrogels, alkanethiols, silanes, polymers and nanoparticles) in complex user-defined patterns. Features generated by DPN are very uniform, so assays constructed with these features deliver exceptional reproducibility.

Illustration of DPN liquid deposition

Molecular or Liquid Deposition

DPN has the flexibility to either print small molecules directly (as “molecular ink”) or to print materials in a liquid carrier (as “liquid ink.”)  With molecular inks, feature size is controlled by varying the meniscus size and tip-surface contact time, resulting in features as small as 50 nm and as large as 1 µm .  The liquid ink technique incorporates material to be printed in a liquid carrier; feature size ranges from <1 - 10 µm and is controlled using liquid-surface affinity, surface contact time, and environmental conditions.

Top-Down vs. Bottom-Up Fabrication

Since it always adds material to a surface or structure, DPN is generally considered to be a “bottom-up” or “additive” technique.  In it’s simplest form, DPN deposits material directly on a flat surface to rapidly fabricate structures such as metal nanoparticles, carbon nanotubes, or protein arrays.  DPN can also print directly to pre-existing nano or microstructures like sensors, PDMS stamps, microfluidics, or photomasks. When used in combination with other fabrication techniques (such as

Close up view of DPN molecular deposition

etching, self-assembly, and in situ polymerization), DPN enables the creation of complex nanomaterials and nanostructures and provides both “top down” and “bottom up” capabilities. The blending of etching and DPN methods is ideal for the rapid prototyping of nanoscale diffraction gratings, plasmonic features, and arbitrary solid-state patterns (including photomasks) in a more traditional top down manner. 

NanoEncryption Technology

NanoInk’s NanoGuardian™ division leverages NanoEncryption™ technology to deliver brand protection solutions that enable pharmaceutical manufacturers to authenticate and trace the integrity of their products across the supply chain, thereby fighting illegal diversion and counterfeiting.  Find out more about NanoEncryption at www.nanoguardian.net.