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We introduce a novel dry wafer bonding concept designed for permanent attachment of micromolded polymer structures to surface functionalized silicon substrates. The method, designed for simultaneous fabrication of many lab-on-chip devices, utilizes a chemically reactive polymer microfluidic structure, which rapidly bonds to a functionalized substrate via "click" chemistry reactions. The microfluidic structure consists of an off-stoichiometry thiol-ene (OSTE) polymer with a very high density of surface bound thiol groups and the substrate is a silicon wafer that has been functionalized with common bio-linker molecules. We demonstrate here void free, and low temperature (<37 degrees C) bonding of a batch of OSTE microfluidic layers to a silane functionalized silicon wafer., QC 20120903. Updated from submitted to published.

Three-dimensional (3D) integration is an emerging technologythat vertically interconnects stacked dies of electronics and/orMEMS-based transducers using through silicon vias (TSVs).TSVs enable the realization of devices with shorter signal lengths,smaller packages and lower parasitic capacitances, which can resultin higher performance and lower costs of the system. Inthis paper we demonstrate a new manufacturing technology forhigh-aspect ratio (> 8) through silicon metal vias using magneticself-assembly of gold-coated nickel rods inside etched throughsilicon-via holes. The presented TSV fabrication technique enablesthrough-wafer vias with high aspect ratios and superior electricalcharacteristics. This technique eliminates common issues inTSV fabrication using conventional approaches, such as the metaldeposition and via insulation and hence it has the potential to reducesignificantly the production costs of high-aspect ratio stateof-the-art TSVs for e.g. interposer, MEMS and RF applications., © 2012 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.QC 20120618

This paper reports on the realization of a novel method for batch transfer of multiple separate dies from a smaller substrate onto a larger wafer substrate by using a standard matrix expander in combination with an elastic dicing tape and adhesive wafer bonding. We demonstrate the expansion and transfer of about 30 000 dies from a 100-mm wafer format to a 200-mm wafer. Furthermore, multiple expansions of 100-mm wafers diced into 60 000 dies are evaluated to determine the position accuracy between different expansions. Fabrication, evaluation method, and results are presented., QC 20121116

We present a method for PDMS microfabrication of fragile membranes and 3D fluidic networks, using a surface modified water-dissolvable release material, poly(vinyl alcohol), as a tool for handling, transfer and release of fragile polymer microstructures. The method is well suited for the fabrication of complex multilayer microfluidic devices, here shown for a PDMS device with a thin gas permeable membrane and closely spaced holes for vertical interlayer connections fabricated in a single layer. To the authors knowledge, this constitutes the most advanced PDMS fabrication method for the combination of thin, fragile structures and 3D fluidics networks, and hence a considerable step in the direction of making PDMS fabrication of complex microfluidic devices a routine endeavour., QC 20150624

A novel method for transferring thin, large-area polymer layers from a mould and its subsequent bonding to a destination substrate is presented here. Buoyancy is used for transfer via floatation to allow the release of internal stress in the polymer and to avoid induced strain. Additionally, floatation leads to wrinkle-free contact between the polymer layer and its destination substrate, an important feature for the transfer of large-area polymer sheets. Poly(vinyl alcohol) is used as a release film on the mould, from which the device polymer layer is released using ultrasonication. The polymer layer floats from the mould to a destination surface, to which it automatically aligns. Here, the method is demonstrated by the successful manufacturing of a 4 '' sized, triple microfluidic layer PDMS stack on a silicon wafer, containing a total of 48 large-area, fragile membranes, each with a thickness of 50 mu m., QC 20120730

Through-silicon via (TSV) technology enables 3D-integrated devices with higher performance and lower cost as compared to 2D-integrated systems. This is mainly due to smaller dimensions of the package and shorter internal signal lengths with lower capacitive, resistive and inductive parasitics. This paper presents a novel low-cost fabrication technique for metal-filled TSVs with very high aspect ratios (>20). Nickel wires are placed in via holes of a silicon wafer by an automated magnetic assembly process and are used as a conductive path of the TSV. This metal filling technique enables the reliable fabrication of through-wafer vias with very high aspect ratios and potentially eliminates characteristic cost drivers in the TSV production such as advanced metallization processes, wafer thinning and general issues associated with thin-wafer handling., QC 20120827

Food allergies can provoke severe clinical reactions. Within the FP7 project POSITIVE a Lab-on-a-Chip platform for label-free quantitative allergen testing is under development. The system integrates fluidic handling, optical interrogation and a porous Silicon based bio sensor cartridge. Optical and fluidic concepts have been derived and partially tested with positive results on lab bench level. Further effort has to be spent on higher system integration and miniaturization of the components as well as signal processing and data evaluation. Model tests based on the immobilization of allergens and molecular recognition by specific antibodies have been established proofing the pre-treated porous Silicon membranes bio assay suitability., QC 20130115. QC 20220315, Positive

In this work we have developed a simple and robust method to permanently pattern alternating hydrophobic and hydrophilic surfaces in off-stoichiometry thiol-ene (OSTE) polymer microchannels. By being able to tune the number of unreacted thiol surface groups of the OSTE Thiol polymers and by taking advantage of spatially photo-controlled surface grafting of methacrylate monomers we achieve defined areas with contact angles from 20° to 115° within one single channel. The surface modification remains stable after storage in air (>2 months) or water (>24h)., QC 20121120

To fabricate complex microfluidic devices in a rapid manner, we have developed a novel method for simultaneous patterning of two sides of a single layer of PDMS using double-sided micromoulding. A mould surface coating containing aminosilanised poly(vinyl alcohol) (PVA) provides low-stress release of fragile polymer structures from the mould as well as inhibition of PDMS polymerisation at through-hole locations, thus enabling fabrication of membranes and 3D microfluidic networks in a single step. Alignment of the top and bottom patterns is achieved already during the moulding step using guiding structures in the mould halves, leading to a procedure with a minimum number of alignment and bonding steps needed to fabricate fragile 3D microfluidic devices., QC 20130110. QC 20160314

We present an entirely novel, self-limiting photolithography mechanism in off-stoichiometry thiol-ene (OSTE) polymers enabling high-resolution and high-aspect ratio features. The OSTE polymers have previously been shown to be promising materials for fabrication of microfluidic devices with tailored surface modifications and mechanical properties. We here introduce direct lithography for micropatterning of OSTE as an alternative to mechanical machining or casting, resulting in a simple and reliable fabrication method of self-bonding photopatterned multilayer microfluidic devices., QC 20220623Part of proceedings: ISBN 978-0-9798064-5-2

In this article we introduce a novel polymer platform based on off-stoichiometry thiol–enes (OSTEs), aiming to bridge the gap between research prototyping and commercial production of microfluidic devices. The polymers are based on the versatile UV-curable thiol–ene chemistry but takes advantage of off-stoichiometry ratios to enable important features for a prototyping system, such as one-step surface modifications, tuneable mechanical properties and leakage free sealing through direct UV-bonding. The platform exhibits many similarities with PDMS, such as rapid prototyping and uncomplicated processing but can at the same time mirror the mechanical and chemical properties of both PDMS as well as commercial grade thermoplastics. The OSTE-prepolymer can be cast using standard SU-8 on silicon masters and a table-top UV-lamp, the surface modifications are precisely grafted using a stencil mask and the bonding requires only a single UV-exposure. To illustrate the potential of the material we demonstrate key concepts important in microfluidic chip fabrication such as patterned surface modifications for hydrophobic stops, pneumatic valves using UV-lamination of stiff and rubbery materials as well as micromachining of chip-to-world connectors in the OSTE-materials., QC 20110831, Intopsens

QC 20120328

We introduce and demonstrate a method for low-stress demolding and transfer of polymer microstructures from their mold to a destination wafer. This method has the advantage of not involving stress-inducing handling steps present in traditional demolding and transfer bonding procedures. The mold is coated with a sacrificial layer which is dissolved in an ultrasonication water bath, leading to that the polymer sheet floats to the water surface. This generic method facilitates transfer of large area, thin layers and is here demonstrated for demolding and transfer bonding of wafer-sized layers of microstructured PDMS., Poster presentationQC 20111118

We report on the successful manufacturing and operation of the first PDMS-based PCR microreactor with continuous on-chip debubbling. A semipermeable membrane between the PCR chamber and a low-pressure chamber allows air bubbles to escape from the PCR chamber, while preventing significant water loss, thus solving one of the major problems in on-chip PCR. Moreover, a novel PDMS microfabrication process for the PCR chip is described. Finally we demonstrate successful on-chip PCR amplification., Poster presentation.QC 20111118

We present a low temperature (< 37°C) wafer-scale microfluidic batch packaging process using covalent, dry bonding of offstoichiometry thiol-ene polymers (OSTE), enabling rapid, bio-compatible integration of fluidics on wafer-scale in combination with excellent polymer properties., QC 20111130

We propose and demonstrate a novel one step method to integrate gold coated sensors with cartridges by dry covalent bonding. The cartridges are replica molded in an UV-curable off-stoichiometry thiol-ene (OSTE) polymer, featuring an excess of thiol functional groups that covalently bond to the surface of gold coated sensors upon contact. The method is demonstrated by the integration of a gold coated quartz crystal to a microfludic OSTE cartridge. The resulting bond interface is shown to be completely homogenous and void free and the package is tested successfully to a differential pressure of up to 2 bars. The performance of the biosensor chip is evaluated by measuring the unspecific binding of 0.5% albumin, resulting in a total frequency drop 205 Hz. This approach delivers a simple but rapid high quality integration aiming for the production of robust, low cost and disposable biosensor chips, QC 20111129, RPA, Rappid

Three-dimensional (3D) integration of electronics and/or MEMS-based transducers is an emerging technology that vertically interconnects stacked dies using through silicon vias (TSVs). They enable the realization of devices with shorter signal lengths, smaller packages and lower parasitic capacitances, which can result in higher performance and lower costs of the system. This paper presents a novel low-cost fabrication technique for solid metal-filled TSVs using nickel wires as conductive path. The wires are placed in the via hole of a silicon wafer by magnetic self-assembly. This metal filling technique enables through-wafer vias with high aspect ratios and potentially eliminates characteristic cost drivers of the TSV production such as metallization processes, wafer thinning and general issues associated with thin-wafer handling., © 2011 IEEE. Personal use of this material is permitted. Permission from IEEE must be obtained for all other uses, in any current or future media, including reprinting/republishing this material for advertising or promotional purposes, creating new collective works, for resale or redistribution to servers or lists, or reuse of any copyrighted component of this work in other works.QC 20111110

Point-of-care diagnostic devices typically require six distinct qualities: they must deliver at least the same sensitivity and selectivity, and for a cost per assay no greater than that of today's central lab technologies, deliver results in a short period of time (<15 min at GP; <2h in hospital), be portable or at least small in scale, and require no or extremely little sample preparation. State-of-the-art devices deliver information of several markers in the same measurement., QC 20110509

This paper presents an uncomplicated high-yield fabrication process for creating large-scale integrated (LSI) 3-D microfluidic networks in poly(dimethylsiloxane) (PDMS). The key innovation lays in the robust definition of miniaturized out-of-plane fluidic interconnecting channels (=vias) between stacked layers of microfluidic channels in standard PDMS. Unblocked vias are essential for creating 3-D microfluidic networks. Previous methods either suffered from limited yield in achieving unblocked vias due to residual membranes obstructing the vias after polymerization, or required complicated and/or manual procedures to remove the blocking membranes. In contrast, our method prevents the formation of residual membranes by inhibiting the PDMS polymerization on top of the mold features that define the vias. In addition to providing unblocked vias, the inhibition process also leaves a partially cured, sticky flat-top surface that adheres well to other surfaces and that allows self-sealing stacking of several PDMS layers. We demonstrate the new method by manufacturing a densely perforated PDMS membrane and an LSI 3-D PDMS microfluidic channel network. We also characterize the inhibition mechanism and study the critical process parameters. We demonstrate that the method is suitable for structuring PDMS layers with a thickness down to 10 mu m., QC 20110127

QC 20111123, Rappid

QC 20111118

QC 20111129, Rappid

We present an easy to use, rapid fabrication platform for microfluidic systems, based on micro-molding of novel thiolene based polymer formulations. The novel fabrication platform addresses major drawbacks of PDMS by allowing large freedom in material and surface properties, including: (photo)patterning of stable surface modifications, bonding without plasma treatment, rapid UV or thermal curing, variable E-modulus, minimized leaching of uncured components [1] and suppressed non-specific binding of biomolecules [2]. This process is potentially suited for both rapid prototyping in the laboratory and medium-scale commercial production, bridging the “development gap”., QC 20140819, Intopsens