Silicon-Containing Spin-on Underlayer Material for Step and Flash Nanoimprint Lithography

Abstract

Nanoimprint lithography is a newly developed patterning method that employs a hard template for the patterning of structures at micro- and nanometer scales. This technique has many advantages such as cost reduction, high resolution, low line edge roughness (LER), and easy operation. However, resist peeling, defects, low degree of planarization, and low throughput issues present challenges that must be resolved in order to mass produce advanced nanometer-scale devices. In this study, the new approach of using a silicon-containing spin-on hard mask underlayer material with high adhesion by reacting methacrylate groups of the underlayer to the acrylate groups of resist material during ultraviolet irradiation was demonstrated to obtain the excellent patterning dimensional accuracy and increase the process latitudes. The performance of this process is evaluated by using step and flash imprint lithography. The obtained high adhesion between the underlayer and resist material was found to lead a silicon-containing underlayer material to excellent patterning dimensional accuracy and 80 nm straight profiles. We expect that the silicon-containing a spin-on hard mask material under organic resist will be one of the most promising materials in the next generation of nanoimprint lithography.

Planarizing material for reverse-tone step and flash imprint lithography

“…In the first step, substrates coated with an underlayer, NCI-NIL-01 (Nissan Chemical Industries, Ltd., Chiba, Japan), were prepared. 12 The purpose of the underlayer or transfer layer is to improve adhesion and to provide a mask for subsequent etch process. In the second step, imprints were carried out on an Imprio 100® (Molecular Imprints Inc., Austin, Texas) S-FIL tool installed at the University of Texas at Austin.…”

Ultraviolet curing nanoimprint green lithography using water-repellent film derived from biomass for solar cells devices

“…The master template was then removed from the replica template. An underlayer TPU-NIL-U01 was manually dispensed and spun to the appropriate thickness based on the dry etching processes, and then polymerized at 200 °C for 60 sec.. Three glucose derivatives with UV curable groups or fluorinated alkyl group in ecofriendly water-repellent film TPU-Green2014 was dispensed onto the TPU-NIL-U01 was used as the adhesion underlayer [22][23]. TPU-Green2014 was pressed with the replica template and was filled at room temperature for 90 sec.…”

“…The high adhesion between the silicon-containing underlayer and the nanoimprint material material led to excellent patterning fidelity and straight 80 nm resist profiles [10]. A trehalose derivative resist material with specific desired properties capable of producing 80 nm resolution was successfully developed for SFIL as an UV curing nanoimprint green lithography [11].…”

Ecofriendly antiglare film derived from biomass using ultraviolet curing nanoimprint lithography for high-definition display

“…The resist material TPU-AGFGreen1 was dispensed onto the underlayer, and TPU-NIL-U01 was used as the adhesion layer. 19,20 TPU-NIL-U01 was manually dispensed and spun to the appropriate thickness based on the dry etching processes and then polymerized at 200°C for 60 s. TPU-AGF-Green1 was pressed with the replica template and was filled at room temperature for 120 s. The imprint force was 60 N. TPU-AGF-Green1 was then irradiated by brief ultraviolet irradiation, forming the desired pattern with pillar patterns of 230-nm diameter and 200-nm height. Ultraviolet irradiation was carried out by using a metal halide lamp system (Sun Energy, broad band targeted for the 365-nm peak, ultraviolet exposure dose: 40 mW∕cm 2 for 5 min).…”