NIL – Nanoimprint Lithography

Printing of Microfluidic Structures

Nanoimprint Lithography (NIL) is a popular approach to make disposable microfluidic devices at low numbers. µCP4.1 does the whole process in an unattended run. The instrument has to be supplied with a curable fotopolymer as well as with the printing substrate.

Instead of transferring an ink, the elevated patterns of the PDMS stamp shape their reverse image into a homogeneous layer on the stamp target. In a preceding step, the target surface has to be coated with an appropriated material, e.g. a liquid, UV-hardened, polymer. µCP 4.1 automatically produces homogenuous polymer layers by dispensing and spinning.

Resist dispensing/ Spinning

Resist dispensing/ Spinning

Drying

Drying

Stamping

Stamping

Graves/ Cavities are done

Graves/ Cavities are done

Curing/ Hardening

Curing/ Hardening

3D structures can be printed with SU8 photoresist or NOA (Norland). Heights of up to 150 microns are feasible. The aspect ratio height : width depends on the layout but can easily reach (3…5) : 1.

After detaching of the stamp the printed substrates can be sealed by cover lids in order to achieve microfluidic devices.