Masterless Soft Lithography:  Patterning UV/Ozone−Induced Adhesion on Poly(dimethylsiloxane) Surfaces

Abstract

A novel microreactor-based photomask capable of effecting high resolution, large area patterning of UV/ozone (UVO) treatments of poly(dimethylsiloxane) (PDMS) surfaces is described. This tool forms the basis of two new soft lithographic patterning techniques that significantly extend the design rules of decal transfer lithography (DTL). The first technique, photodefined cohesive mechanical failure, fuses the design rules of photolithography with the contact-based adhesive transfer of PDMS in DTL. In a second powerful variation, the UVO masks described in this work enable a masterless soft lithographic patterning process. This latter method, UVO-patterned adhesive transfer, allows the direct transfer of PDMS-based polymer microstructures from a slab of polymer to silicon and other material surfaces. Both methods exploit the improved process qualities that result from the use of a deuterium discharge lamp to affect the UVO treatment to pattern complex, large area PDMS patterns with limiting feature sizes extending well below 1 microm (> or = 0.3 microm). The use of these structures as resists is demonstrated for the patterning of metal thin films. A time-of-flight secondary ion mass spectroscopy study of the process provides new insights into the mechanisms that contribute to the chemistry responsible for the interfacial adhesion of DTL transfers.

Large‐Area, Selective Transfer of Microstructured Silicon: A Printing‐ Based Approach to High‐Performance Thin‐Film Transistors Supported on Flexible Substrates

“…The selective-area soft-lithographic patterning procedure, following literature procedures [16], consisted of placing the unpatterned PDMS side of the coated PET substrate in contact with the patterned side of the UVO photomask. The fabrication of this microreactor mask followed procedures described by Childs et al [16].…”

“…Method I exploits physical bonding between a molded Sylgard 3600 polydimethylsiloxane (PDMS) stamp (a new experimental, high-modulus PDMS product provided by the Dow Corning Corp.) and ls-Si objects. Method II uses a recently developed masterless soft-lithography technique [16] to chemically bond the ls-Si to a PDMS-coated substrate. In Method I, shown in Scheme 1a, a peanut-shaped photoresist pattern was developed on top of a SOI substrate using standard photolithography techniques.…”

“…Method II is depicted in Scheme 1b. This recently reported decal-transfer lithography (DTL) technique [16] effects the pattern transfer by using a flat, unmolded PDMS slab that is photochemically treated to provide spatially modulated strengths of adhesion. To do so, an UVO treatment was patterned across the surface of a slab of conventional Sylgard 184 PDMS using a microreactor photomask to pattern the UVO modification with high spatial resolution.…”

Bifunctional Polymer-Metal Nanocomposite Ion Exchange Materials

“…Particular industries, including the oil and the automobile ones, are interested in this area for the use of NPs in catalytic converters. [81] As a prove of their industrial potentiality, many big companies, including BASF, Johnson Matthey and 3M, have interests in developing commercial applications for AuNPs catalysts.…”

Deposition of Carbon Nanotube Films on Polyamide and Polypropylene Substrates: A Computer Simulation Approach

“…The main effects of these treatments include cleaning (conversion of liquid films or solid contaminants into gaseous, volatile products), ablation/etching out of weak layers at the microscopic scale or even, selective etching of low molecular weight polymer chains and modification of chemical structures of surfaces through reactions of free radicals with surrounding gases 7,8,10,[13][14][15] . Out of these techniques, the UV/O 3 treatment/exposure is a convenient dry oxidizing method for activating the physicochemical features of polymer surfaces and other carbon materials 14 .…”