Shrinkage Control of Photoresist for Large‐Area Fabrication of Sub‐30 nm Periodic Nanocolumns

Abstract

A method to fabricate large‐area arrays of nanocolumns without a deep‐UV laser source is reported. This method allows high‐yield fabrication of 3 × 3 cm2 arrays of sub‐30 nm nanocolumns made of bottom antireflection layer coating (BARC) by combining displacement Talbot lithography (DTL) using a monochromatic UV beam (365 nm wavelength) with plasma etching techniques. DTL is used to manufacture an initial pattern of periodic photoresist nanocolumns with a diameter of ≈110 nm. N2 plasma can transfer this pattern at a 1:1 ratio to BARC nanocolumns. It is found that reactive O2/N2 plasma etching on the other hand can shrink the BARC nanocolumns to sub‐30 nm dimensions. The shrink‐etching process can be reproducibly controlled by tuning the gas flow ratio and the etching time. It is highly remarkable that the verticality of these BARC nanocolumns remains during O2/N2 plasma shrink etching. Combining the etching of O2/N2 plasma with N2 plasma allows to produce BARC nanocolumns over the entire diameter range from 110 to sub‐30 nm. The fabrication approach enables large‐footprint fabrication of size‐tunable periodic nanostructures that have many potential applications in photonics, electronics, biosensors, smart surfaces, catalysis, and biomedical analysis.

Wafer-scale fabrication of high-quality tunable gold nanogap arrays for surface-enhanced Raman scattering

“…1d). These plasma etching processes were conducted using a wafer-scale parallel plate reactive ion etching system (in-house built TEtske system, NanoLab Cleanroom) at 13 mTorr, and 25 W. 17 Patterning periodic Cr nanolines using lift-off process A thin Cr layer of approximately 6 nm was deposited over the surface of the patterned wafer using a sputtering system (in- house built T'COathy system, NanoLab Cleanroom) (Fig. 1e).…”

“…To overcome this limitation, we developed a robust technique for shrink-etching the patterned PR nanostructures using a mixture of O 2 /N 2 plasma. 17 As a result, bottom antireflection coating (BARC) nanostructures with dimensions down to sub-30 nm could be reliably fabricated from the initially patterned PR nanostructures.…”

Large-scale fabrication of free-standing and sub-μm PDMS through-hole membranes

“…1d ). After baking the Si-wafer in an oven at 80 °C for at least 3 h, a plasma etching process of the PDMS membrane was conducted in a parallel plate reactive ion etching system (in-house built TEtske system) 30 at 47 sccm SF 6 , 17 sccm O 2 , 50 mTorr, and 100 W to decrease the thickness of the PDMS membrane and open the through-holes ( Fig. 1e ).…”

Displacement Talbot lithography nanopatterned microsieve array for directional neuronal network formation in brain-on-chip

“…As introduced above, the DTL permits good pattern uniformity on a nonflat surface. 17 However, the topography of the microsieve array may still cause thickness nonuniformity in the coatings which leads to a poor pattern transfer result. Therefore, we introduced a planarizing layer by precoating a positive resist prior to the DTL experiment to overcome the nonuniformity problem.…”