Soft UV Nanoimprint Research Articles

Improved mold fabrication for the definition of high quality nanopatterns by Soft UV-Nanoimprint lithography using diluted PDMS material

An improved mold fabrication process that utilizes toluene diluted polydimethylsiloxane (PDMS) as flexible mold material was developed. Various toluene concentrations and their implication on the pattern definition using the Soft UV-Nanoimprint process were analyzed and discussed. Dots with a resolution of 50 nm are well replicated and an excellent imprint homogeneity across a 4 in. wafer with one imprint step only is demonstrated.

Fabrication of SOI photonic crystal slabs by soft UV-nanoimprint lithography

Soft imprinting lithography assisted by UV light (soft UV-NIL) takes advantage of both, UV-nanoimprint and soft lithography. This technique, which can be applied for the replication of nanometer size features over large areas, is suitable for the patterning of nanostructures like photonic crystals with high throughput and high accuracy. In this work, we demonstrate the fabrication of two dimensional silicon-on-insulator photonic crystal slabs with and without line defects by using soft UV-NIL. Measurement of photonic mode dispersion by means of variable angle reflectance assesses the quality of the fabricated samples.

High resolution lithography with PDMS molds

The resolution, dimension stability, and reproducibility of the Soft UV-Nanoimprint is investigated. The potential for imprinting nanostructures with flexible molds in UV-curable resists in the 100nm regime are explored and the limitations analyzed. The dimensional stability of imprinted patterns is determined by the deformation of the mold that in term depends on the geometry of the structures and the imprint pressure applied.

Wafer scale patterning by soft UV-Nanoimprint Lithography

Wafer scale patterning by soft UV-Nanoimprint Lithography

Wafer scale patterning by soft UV-Nanoimprint Lithography

We present first results on wafer scale patterning within one imprint step only, using Soft UV-Nanoimprint Lithography (UV-NIL). In this process, flexible transparent stamps, fabricated by cast moulding ensure a conformal contact, whereas the usage of low viscosity UV-curable resists allows three-dimensional pattern generation at low pressure (<1 bar) and room temperature. Technical aspects that will be covered in this paper include the master and stamp fabrication and a new imprint tool, developed by EV Group, Austria. To demonstrate the applicability of this technique, imprints on 100 mm silicon wafers have been analysed with special emphasis to the residual resist thickness h r. In addition, data on the dimensional stability of the imprint process are presented.