de Bj Berend-Jan Gans

Bio: de Bj Berend-Jan Gans is an academic researcher from Eindhoven University of Technology. The author has contributed to research in topics: Etching (microfabrication) & Printed electronics. The author has an hindex of 3, co-authored 4 publications receiving 2308 citations.

Inkjet Printing of Polymers: State of the Art and Future Developments

Abstract: Inkjet printing is considered to be a key technology in the field of defined polymer deposition. This article provides an introduction to inkjet printing technology and a short overview of the available instrumentation. Examples of polymer inkjet printing are given, including the manufacturing of multicolor polymer light-emitting diode displays, polymer electronics, three-dimensional printing, and oral dosage forms for controlled drug release. Special emphasis is placed upon the utilized polymers and conditions, such as polymer structure, molar mass, solvents, and concentration. Studies on viscoelastic fluid jets and the formation of viscoelastic droplets under gravity indicate that strain hardening is the key parameter that determines the inkjet printability of polymer solutions.

Ink‐jet Printing and Microwave Sintering of Conductive Silver Tracks

Abstract: Printing techniques, such as ink-jet printing, are interesting alternatives to conventional photolithography for the production of electronic devices. The advantages of printing include the ease of mass production, low cost, and flexibility. Compared to other printing techniques (e.g., screen printing), ink-jet printing does not offer the same production speed. However, the unprecedented flexibility of ink-jet printing makes it very well suited for rapid prototyping applications. In addition, it allows the use of inviscid fluids, such as dilute polymer solutions or suspensions without added binders. A typical application involves the ink-jet printing of conductive tracks, for example, by using inks based on (in)organic silver or copper precursors. The precursor is reduced to the corresponding metal via a post-printing thermal annealing step. In most cases, however, the ink is a dispersion of noble-metal nanoparticles, usually silver or gold. A sintering step is necessary to render the tracks conductive. The use of nanoparticles reduces the sintering temperature due to their high surface to volume ratio. In the past, two different techniques have been used to sinter printed nanoparticle structures. Conventional radiation– conduction–convection heating is the most commonly used method, wherein the sintering temperatures are typically above 200 °C. Therefore many potentially interesting substrate materials, such as thermoplastic polymers or paper, cannot be used. In fact, one of the very few, if not the only organic substrate that can be used is (expensive) polyimide (PI). The long sintering times required—usually 60 min or more— also imply that the technique is not feasible for fast industrial production. As an alternative, a laser sintering method was developed. The laser follows the conductive tracks and sinters these selectively, without affecting the substrate. However, this method is costly and complex from a technical point of view. Thus, there is a clear need for a fast, simple, and costeffective technique that would allow the sintering of the printed structures by the selective heating of only the printed components. Microwave heating fulfills these requirements. Microwave heating is widely used for the sintering of dielectric materials and in synthetic chemistry. It offers advantages such as uniform, fast, and volumetric heating. Microwave radiation is absorbed due to coupling with charge carriers or rotating dipoles. The absorbed power per unit volume P is,

Inkjet Printing of Functional Polymers and Materials: 2nd International Workshop in Eindhoven

Abstract: This section contains reports on topical conferences. Reports are usually written at the request of the editorial office, but unsolicited contributions are also welcome. Suggestions should be sent to the editorial office of the Macromolecular journals, preferably by E-mail to macromol@wiley-vch.de.

The status, challenges, and future of additive manufacturing in engineering

Abstract: Additive manufacturing (AM) is poised to bring about a revolution in the way products are designed, manufactured, and distributed to end users. This technology has gained significant academic as well as industry interest due to its ability to create complex geometries with customizable material properties. AM has also inspired the development of the maker movement by democratizing design and manufacturing. Due to the rapid proliferation of a wide variety of technologies associated with AM, there is a lack of a comprehensive set of design principles, manufacturing guidelines, and standardization of best practices. These challenges are compounded by the fact that advancements in multiple technologies (for example materials processing, topology optimization) generate a "positive feedback loop" effect in advancing AM. In order to advance research interest and investment in AM technologies, some fundamental questions and trends about the dependencies existing in these avenues need highlighting. The goal of our review paper is to organize this body of knowledge surrounding AM, and present current barriers, findings, and future trends significantly to the researchers. We also discuss fundamental attributes of AM processes, evolution of the AM industry, and the affordances enabled by the emergence of AM in a variety of areas such as geometry processing, material design, and education. We conclude our paper by pointing out future directions such as the "print-it-all" paradigm, that have the potential to re-imagine current research and spawn completely new avenues for exploration. The fundamental attributes and challenges/barriers of Additive Manufacturing (AM).The evolution of research on AM with a focus on engineering capabilities.The affordances enabled by AM such as geometry, material and tools design.The developments in industry, intellectual property, and education-related aspects.The important future trends of AM technologies.

Stretchable form of single crystal silicon for high performance electronics on rubber substrates

Abstract: The present invention provides stretchable, and optionally printable, semiconductors and electronic circuits capable of providing good performance when stretched, compressed, flexed or otherwise deformed. Stretchable semiconductors and electronic circuits of the present invention preferred for some applications are flexible, in addition to being stretchable, and thus are capable of significant elongation, flexing, bending or other deformation along one or more axes. Further, stretchable semiconductors and electronic circuits of the present invention may be adapted to a wide range of device configurations to provide fully flexible electronic and optoelectronic devices.

Materials and applications for large area electronics: solution-based approaches.

Abstract: 2.3. Medical Devices and Sensors 9 2.4. Radio Frequency Applications 10 3. Materials 12 3.1. Organic Electronics Materials 12 3.2. Semiconducting Polymer Design 13 3.3. Poly(3-alkylthiophenes) 14 3.4. Poly(thieno(3,2-b)thiophenes 15 3.5. Benchmark Polymer Semiconductors 15 3.6. High Performance Polymer Semiconductors 15 4. Device Stability 16 4.1. Bias Stress in Organic Transistors 17 4.1.1. Bias Stress Characterization 17 4.1.2. Bias Stress Mechanism 18 4.2. Short Channel Effects in Organic Transistors 19 5. Materials Patterning and Integration 20 6. Conclusions 22 7. Acknowledgments 22 8. References 22

Inkjet Printing of Functional and Structural Materials: Fluid Property Requirements, Feature Stability, and Resolution

Abstract: Inkjet printing is viewed as a versatile manufacturing tool for applications in materials fabrication in addition to its traditional role in graphics output and marking. The unifying feature in all these applications is the dispensing and precise positioning of very small volumes of fluid (1–100 picoliters) on a substrate before transformation to a solid. The application of inkjet printing to the fabrication of structures for structural or functional materials applications requires an understanding as to how the physical processes that operate during inkjet printing interact with the properties of the fluid precursors used. Here we review the current state of understanding of the mechanisms of drop formation and how this defines the fluid properties that are required for a given liquid to be printable. The interactions between individual drops and the substrate as well as between adjacent drops are important in defining the resolution and accuracy of printed objects. Pattern resolution is limited by the extent to which a liquid drop spreads on a substrate and how spreading changes with the overlap of adjacent drops to form continuous features. There are clearly defined upper and lower bounds to the width of a printed continuous line, which can be defined in terms of materials and process variables. Finer-resolution features can be achieved through appropriate patterning and structuring of the substrate prior to printing, which is essential if polymeric semiconducting devices are to be fabricated. Low advancing and receding contact angles promote printed line stability but are also more prone to solute segregation or “coffee staining” on drying.