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Pattern Transfer (pattern + transfer)

Distribution by Scientific Domains

Polymers and Materials Science	100%

Selected Abstracts

Intact Pattern Transfer of Conductive Exfoliated Graphite Nanoplatelet Composite Films to Polyelectrolyte Multilayer Platforms,

ADVANCED MATERIALS, Issue 10 2008
Troy R. Hendricks
A simple method for creating patterned conductive multilayered polymer/exfoliated graphite nanoplatelet (xGnP) nanocomposite films is presented, by using the LBL assembly of xGnP and the intact pattern transfer of these films to a substrate. After four bilayers are deposited onto the stamp, conductive patterns can be created on virtually any substrate. [source]

Reactive Imprint Lithography: Combined Topographical Patterning and Chemical Surface Functionalization of Polystyrene- block -poly(tert -butyl acrylate) Films

ADVANCED FUNCTIONAL MATERIALS, Issue 3 2010
Joost Duvigneau
Abstract Here, reactive imprint lithography (RIL) is introduced as a new, one-step lithographic tool for the fabrication of large-area topographically patterned, chemically activated polymer platforms. Films of polystyrene- block -poly(tert -butyl acrylate) (PS- b -PtBA) are imprinted with PDMS master stamps at temperatures above the corresponding glass transition and chemical deprotection temperatures to yield structured films with exposed carboxylic acid and anhydride groups. Faithful pattern transfer is confirmed by AFM analyses. Transmission-mode FTIR spectra shows a conversion of over 95% of the tert -butyl ester groups after RIL at 230,°C for 5 minutes and a significantly reduced conversion to anhydride compared to thermolysis of neat films with free surfaces in air or nitrogen. An enrichment of the surface layer in PS is detected by angle-resolved X-ray photoelectron spectroscopy (XPS). In order to demonstrate application potentials of the activated platforms, a 7,nm,±,1,nm thick NH2 -terminated PEG layer (grafting density of 0.9 chains nm,2) is covalently grafted to RIL-activated substrates. This layer reduces the non-specific adsorption (NSA) of bovine serum albumin by 95% to a residual mass coverage of 9.1,±,2.9,ng cm,2. As shown by these examples, RIL comprises an attractive complementary approach to produce bio-reactive polymer surfaces with topographic patterns in a one-step process. [source]

Non-Close-Packed Crystals from Self-Assembled Polystyrene Spheres by Isotropic Plasma Etching: Adding Flexibility to Colloid Lithography

ADVANCED FUNCTIONAL MATERIALS, Issue 20 2009
Alfred Plettl
Abstract Hexagonally ordered arrays of non-close-packed nanoscaled spherical polystyrene (PS) particles are prepared exhibiting precisely controlled diameters and interparticle distances. For this purpose, a newly developed isotropic plasma etching process is applied to extended monolayers of PS colloids (starting diameters <300,nm) deposited onto hydrophilic silicon. Accurate size, shape, and smoothness control of such particles is accomplished by etching at low temperatures (,150,°C) with small rates not usually available in standard reactive ion etching equipment. The applicability of such PS arrays as masks for subsequent pattern transfer is demonstrated by fabricating arrays of cylindrical nanopores into Si. [source]

Simple Patterning via Adhesion between a Buffered-Oxide Etchant-Treated PDMS Stamp and a SiO2 Substrate,

ADVANCED FUNCTIONAL MATERIALS, Issue 13 2007
Y.-K. Kim
Abstract A very simple polydimethylsiloxane (PDMS) pattern-transfer method is devised, called buffered-oxide etchant (BOE) printing. The mechanism of pattern transfer is investigated, by considering the strong adhesion between the BOE-treated PDMS and the SiO2 substrate. PDMS patterns from a few micrometers to sub-micrometer size are transferred to the SiO2 substrate by just pressing a stamp that has been immersed in BOE solution for a few minutes. The patterned PDMS layers work as perfect physical and chemical passivation layers in the fabrication of metal electrodes and V2O5 nanowire channels, respectively. Interestingly, a second stamping of the BOE-treated PDMS on the SiO2 substrate pre-patterned with metal as well as PDMS results in a selective transfer of the PDMS patterns only to the bare SiO2. In this way, the fabrication of a device structure consisting of two Au electrodes and V2O5 nanowire network channels is possible; non-ohmic semiconducting I,V characteristics, which can be modeled by serially connected percolation, are observed. [source]

Siloxane Copolymers for Nanoimprint Lithography,

ADVANCED FUNCTIONAL MATERIALS, Issue 1 2007
P. Choi
Abstract Presented here is the novel use of thermoplastic siloxane copolymers as nanoimprint lithography (NIL) resists for 60,nm features. Two of the most critical steps of NIL are mold release and pattern transfer through dry etching. These require that the NIL resist have low surface energy and excellent dry-etching resistance. Homopolymers traditionally used in NIL, such as polystyrene (PS) or poly(methyl methacrylate) (PMMA), generally cannot satisfy all these requirements as they exhibit polymer fracture and delamination during mold release and have poor etch resistance. A number of siloxane copolymers have been investigated for use as NIL resists, including poly(dimethylsiloxane)- block -polystyrene (PDMS- b -PS), poly(dimethylsiloxane)- graft -poly(methyl acrylate)- co -poly(isobornyl acrylate) (PDMS- g -PMA- co -PIA), and PDMS- g -PMMA. The presence of PDMS imparts the materials with many properties that are favorable for NIL, including low surface energy for easy mold release and high silicon content for chemical-etch resistance,in particular, extremely low etch rates (comparable to PDMS) in oxygen plasma, to which organic polymers are quite susceptible. These properties give improved NIL results. [source]