Fabrication of large-area polymer microfilter membranes and their application for particle and cell enrichment

ABSTRACTThe Step and Flash Imprint Lithography (S-FILTM) process uses field-to-field drop dispensing of UV curable liquids for step and repeat patterning for applications where high-resolution mix-and-match overlay is desired. Several applications, including patterned media, photonic crystals and wire grid polarizers, are better served by a patterning process that prints the full wafer since alignment requirements are not so stringent. In this paper, a methodology for creating high resolution thin templates for full wafer (or disk) imprinting is described. The methods have been applied toward the imprinting of both patterned media and photonic crystal devices using a large area printing tool developed around the S-FIL process. Techniques for further enhancing the pattern density as well as a method for addressing feature image placement are described. Finally, a process for replicating a Master Template is discussed in detail.

Download Full-text

Preparation of Strongly Hydrophobic Film with Large Area and Flexibility Based on Micro Fabrication

Key Engineering Materials ◽

10.4028/www.scientific.net/kem.645-646.195 ◽

2015 ◽

Vol 645-646 ◽

pp. 195-200

Author(s):

Yi Bo Zeng ◽

Ting Ting Wang ◽

Jian Yan Wang ◽

Hang Guo

Keyword(s):

Silicon Wafer ◽

Polyvinylidene Fluoride ◽

Large Scale ◽

Composite Layer ◽

Scale Production ◽

Micro Channel ◽

Large Area ◽

Micro Fabrication ◽

Chemical Grafting ◽

Micro Molding

In order to gain strongly hydrophobic film with large area and flexibility conveniently and effectively, how to prepare film with combination of technologies including micro fabrication, chemical grafting and micro molding is discussed. Firstly, micro channel arrays that the width is 5μm on the silicon wafer are prepared by micro fabrication. Then after spraying PVDF (Polyvinylidene Fluoride) lotion and pouring PDMS (Polydimethylsiloxane) glue solution onto the silicon wafer as the mould successively, the mixture need to be precured, which constructs rough structures in micro and nanoscale on the low surface energy film. Finally chemical grafting for film is carried out under the condition of O2 and 130°C so that the modification layer easy to adhesive on the boundary between PVDF and PDMS can be formed. Through the above technical routes, the strongly hydrophobic film that the general contact angle exceeds above 145o, the area is 180mm×64mm, the thickness is 0.9mm and the composite layer is firmly combined is gained. Compared to other hydrophobic materials the film is available in large area and has an advantage of flexibility. Meanwhile, the way that the film prepared by micro molding and in virtue of the silicon wafer with micro channel arrays as the mould contributes to large scale production.

Download Full-text

Fabrication and modal characterisation of large‐area polymer membranes for acoustic micro‐electromechanical systems devices

Micro & Nano Letters ◽

10.1049/mnl.2018.0089 ◽

2018 ◽

Vol 13 (7) ◽

pp. 989-992

Author(s):

Luca Camellini ◽

Alberto Torin ◽

Asaad K. Al‐mashaal ◽

Graham S. Wood ◽

Michael J. Newton ◽

...

Keyword(s):

Polymer Membranes ◽

Large Area ◽

Electromechanical Systems

Download Full-text

Microtiter Plate-Based Microfluidic Platforms: Sealing, Leakage Testing, and Performance of a 96-Well SPRI Device

Microelectromechanical Systems ◽

10.1115/imece2006-15275 ◽

2006 ◽

Author(s):

D. S. Park ◽

M. Hupert ◽

J. Guy ◽

P. Datta ◽

J.-B. Lee ◽

...

Keyword(s):

High Throughput ◽

Mold Insert ◽

Microfluidic Devices ◽

Microtiter Plate ◽

Thickness Variation ◽

Large Area ◽

Microfluidic Platforms ◽

Effective Manner ◽

Micro Molding ◽

Microtiter Plate Format

Highly parallelized biochemical analysis is a significant step toward achieving high throughput processing of patient samples for diagnosis and treatment monitoring. The standard microtiter plate is used to carry out multiple reactions for high throughput screening. By incorporating polymer microfluidic devices at each well in the microtiter plate format, the capability of the format could be significantly enhanced for high throughput processing of large numbers of biochemical samples in a cost-effective manner. Low cost replication of the microtiter plates is done using micro molding techniques, so microfabrication technology for making large area mold inserts (LAMIs) containing microfluidic devices at each well of a microtiter plate format is needed. A large area mold insert (LAMI) in the footprint of the standard microtiter plate was fabricated using an SU-8 based UV-LIGA technique. Excellent lithography results, with vertical sidewalls, were obtained by utilizing flycutting to minimize SU-8 film thickness variation and a UV filter for attenuating high absorbance UV wavelengths. Overplating of nickel in the SU-8 polymeric molds was used to make high quality metallic mold inserts with vertical sidewalls. Micro molding of polycarbonate (PC) was done using hot embossing, resulting in good replication fidelity over the large surface area. Thermal fusion bonding of the molded PC chips yielded good sealing results and the developed polymer microfluidic platforms showed good fluidic uniformity.

Download Full-text

High quality diffractive optical elements (DOEs) using SMILE imprint technique

Advanced Optical Technologies ◽

10.1515/aot-2020-0053 ◽

2021 ◽

Vol 0 (0) ◽

Author(s):

Simon Drieschner ◽

Fabian Kloiber ◽

Marc Hennemeyer ◽

Jan J. Klein ◽

Manuel W. Thesen

Keyword(s):

Soft Lithography ◽

High Efficiency ◽

Low Cost ◽

Industrial Applications ◽

Diffractive Optical Elements ◽

Large Area ◽

High Quality ◽

Optical Elements ◽

Uv Curable ◽

Aspect Ratios

Abstract Augmented reality (AR) enhancing the existing natural environment by overlaying a virtual world is an emerging and growing market and attracts huge commercial interest into optical devices which can be implemented into head-mounted AR equipment. Diffractive optical elements (DOEs) are considered as the most promising candidate to meet the market’s requirements such as compactness, low-cost, and reliability. Hence, they allow building alternatives to large display headsets for virtual reality (VR) by lightweight glasses. Soft lithography replication offers a pathway to the fabrication of large area DOEs with high aspect ratios, multilevel features, and critical dimensions below the diffractive optical limit down to 50 nm also in the scope of mass manufacturing. In combination with tailored UV-curable photopolymers, the fabrication time can be drastically reduced making it very appealing to industrial applications. Here, we illustrate the key features of high efficiency DOEs and how the SMILE (SUSS MicroTec Imprint Lithography Equipment) technique can be used with advanced imprint photopolymers to obtain high quality binary DOEs meeting the market’s requirements providing a very versatile tool to imprint both nano- and microstructures.

Download Full-text

Fabrication of Photonic Crystal Biosensors using Micro-molding of Nanoporous Glass

MRS Proceedings ◽

10.1557/proc-0900-o03-07 ◽

2005 ◽

Vol 900 ◽

Author(s):

Ian D. Block ◽

Leo L Chan ◽

Brian T Cunningham

Keyword(s):

Photonic Crystal ◽

Sol Gel ◽

Optical Biosensors ◽

Label Free ◽

Large Area ◽

Sem Images ◽

Molding Method ◽

Nanoporous Glass ◽

Substrate Adhesion ◽

Micro Molding

ABSTRACTWe demonstrate a micro-molding method for submicron patterning of a low-index sol-gel nanoporous glass for the purpose of fabricating large-area (∼3”×”) label-free photonic crystal optical biosensors. SEM images show that the sol-gel exhibited minimal shrinkage and good substrate adhesion and depict precise and uniform pattern transfer over the fabricated area within the limits of measurement resolution. A unique characterization approach accurately and quickly revealed porous glass patterned over a large area with geometrical and material properties uniform within 1%. We suggest that this robust method is an excellent approach for photonic crystal sensor fabrication, and may also find applications in integrated optics and electronics.

Download Full-text

Large-area, transferable sub-10 nm polymer membranes at the air–water interface

Nano Research ◽

10.1007/s12274-017-1957-9 ◽

2018 ◽

Vol 11 (7) ◽

pp. 3833-3843 ◽

Cited By ~ 1

Author(s):

Ya Huang ◽

Kai Huang ◽

Naveed Hussain ◽

Hidetoshi Matsumoto ◽

Hui Wu

Keyword(s):

Polymer Membranes ◽

Water Interface ◽

Large Area ◽

Air Water Interface

Download Full-text

Cicada Wing Inspired Template-Stripped SERS Active 3D Metallic Nanostructures for the Detection of Toxic Substances

Sensors ◽

10.3390/s21051699 ◽

2021 ◽

Vol 21 (5) ◽

pp. 1699

Author(s):

Srijit Nair ◽

Juan Gomez-Cruz ◽

Gabriel Ascanio ◽

Aristides Docoslis ◽

Ribal Georges Sabat ◽

...

Keyword(s):

World Health ◽

Excitation Wavelength ◽

Sers Substrate ◽

Toxic Substances ◽

Label Free ◽

Large Area ◽

Uv Curable ◽

Sensing Applications ◽

Label Free Detection ◽

Polarization Independent

This article introduces a bioinspired, cicada wing-like surface-enhanced Raman scattering (SERS) substrate based on template-stripped crossed surface relief grating (TS-CSRG). The substrate is polarization-independent, has tunable nanofeatures and can be fabricated in a cleanroom-free environment via holographic exposure followed by template-stripping using a UV-curable resin. The bioinspired nanostructures in the substrate are strategically designed to minimize the reflection of light for wavelengths shorter than their periodicity, promoting enhanced plasmonic regions for the Raman excitation wavelength at 632.8 nm over a large area. The grating pitch that enables an effective SERS signal is studied using Rhodamine 6G, with enhancement factors of the order of 1 × 104. Water contact angle measurements reveal that the TS-CSRGs are equally hydrophobic to cicada wings, providing them with potential self-cleaning and bactericidal properties. Finite-difference time-domain simulations are used to validate the nanofabrication parameters and to further confirm the polarization-independent electromagnetic field enhancement of the nanostructures. As a real-world application, label-free detection of melamine up to 1 ppm, the maximum concentration of the contaminant in food permitted by the World Health Organization, is demonstrated. The new bioinspired functional TS-CSRG SERS substrate holds great potential as a large-area, label-free SERS-active substrate for medical and biochemical sensing applications.

Download Full-text

Energy Harvesting from Wastewater Using Nanofluidic Reverse Electrodialysis

Innovative Materials and Systems for Energy Harvesting Applications - Advances in Environmental Engineering and Green Technologies ◽

10.4018/978-1-4666-8254-2.ch013 ◽

2015 ◽

pp. 380-411

Author(s):

Kilsung Kwon ◽

Longnan Li ◽

Daejoong Kim

Keyword(s):

Polymer Membranes ◽

Operating Parameters ◽

Nanoporous Membranes ◽

Large Area ◽

Reverse Electrodialysis ◽

Energy Demands ◽

Steady Growth ◽

The World ◽

Modification Technique ◽

Performance Surface

Energy is one of the most important issues in the world owing to the steady growth of energy demands, serious concern about fossil fuel exhaustion, and environmental problems. Reverse electrodialysis (RED), which is a technique to capture the useful energy from mixing the solutions of different concentration, is recently recognized as an efficient method to alleviate the current issue associated with the energy. This chapter reviews the RED studies using nanoporous membranes (named as nanofluidic reverse electordialysis, NRED) in place of conventional polymer membranes having no physical pore. This chapter is made up six parts: the mechanism, the fabrication of nanostructures, the influence of operating parameters (concentration gradient and pore size), the materials, the efforts on enhancing performance (surface modification technique and large area platform), the numerical modeling, and, lastly, the feasible applications.

Download Full-text