Fabrication of a Polymer High-Aspect-Ratio Pillar Array Using UV Imprinting

Abstract

This paper presents UV imprinting methods for fabricating a high-aspect-ratio pillar array. A polydimethylsiloxane (PDMS) mold was selected as the UV imprinting mold. The pillar pattern was formed on a 50 × 50 mm 2 area on a polyethylene terephthalate (PET) film without remarkable deformation. The aspect ratios of the pillar and space were about four and ten, respectively. The mold was placed into contact with a UV-curable resin under a reduced pressure, and the resin was cured by UV light irradiation after exposure to atmospheric pressure. The PDMS mold showed good mold releasability and high flexibility. By moderately pressing the mold before UV-curing, the thickness of the residual layer of the imprinted resin was reduced and the pattern was precisely imprinted. Both batch pressing and roll pressing are available.

Separation of superparamagnetic particles through ratcheted Brownian motion and periodically switching magnetic fields

“…22,23 Therefore, a solution of 0.04% Teflon AF 1600 (DuPont Fluoroproducts) diluted in FC-40 (Acros Organics) was spin coated onto the SU-8 master mold at a speed of 1500 rpm and baked at 120 C for 12 h. 24 Besides allowing for easy demolding, this fluorinated layer also serves as a protective coating for the master mold. 25 Then, PDMS soft lithography was done using the completed SU-8 masters.…”

Recent Situation of the UV Imprint Lithography and Its Application to the Photonics Devices

“…Therefore, it is general to prepare a replica from the master mold. Polydimethylsiloxane (PDMS) is generally used as replica molds for UV-imprint [4]. Recently Shin-Etsu Chemical Co., Ltd. provides UV-curable PDMS (UV-PDMS), which becomes the trigger of solidification.…”

“…First, a mold (or a template) is prepared by using techniques of EBL and reactive ion etching (RIE). A resin pattern is formed by EBL on 2-inches or 3-inches of quartz substrates, and the resin pattern is transferred to the quartz substrates by RIE using F-contained gases, such as CF 4 , and CHF 3 . Figure 2 shows scanning electron microscope (SEM) images of four different quartz molds with various shapes of different period (Λ), height (h), and pillar/pore diameter (φ, in case of 2D pattern).…”

“…2 (A). Etching of the LN has been performed by an electron cyclotron resonance (ECR)-RIE using CF 4 and the Ni pattern as a mask. The etching rate of LN is 9.7 nm/min, and that of Ni is 1.4 nm/min, that is about 7 in selectivity, which is capable to form a relatively deep diffraction grating on the LN substrate.…”

Polydimethyl siloxane wet etching for three dimensional fabrication of microneedle array and high-aspect-ratio micropillars

“…From the literature, most of the PDMS microneedles or micropillars were obtained through soft lithography by casting the PDMS onto the negative molds made of photoresist or silicon, which were produced by photolithographic process 22,23 or silicon dry etching. 24 As to the polymer micropillars, the conventional practice is first to obtain the negative PDMS mold with a hole array, followed by casting the polymer solution 25 or utilizing imprinting technique 26 to produce the polymer micropillars. Different from the literature, our proposed technique is to directly etch the PDMS micropillars to form the microneedles or high-aspect ratio micropillars for subsequent fabrication of polymer microstructures.…”