Jan Vanfleteren - Profile on Academia.edu (original) (raw)

Papers by Jan Vanfleteren

Novel insights regarding the ability of encapsulated metal interconnections to deform due to bend... more Novel insights regarding the ability of encapsulated metal interconnections to deform due to bending are presented. Encapsulated metal interconnections are used as electric conductor or measurement system within a wide range of applications fields, e. g. biomedical, wearable, textile applications. Nevertheless

A Reliable and comfortable package for wearable medical devices

Abstract Various approaches will make wearable medical systems comfortable for the user: circuit ... more Abstract Various approaches will make wearable medical systems comfortable for the user: circuit miniaturization is important, but this approach is ideally combined with flexible and/or stretchable integration, in order to obtain conformable, randomly deformable circuitry. ...

Design and performance of metal conductors for stretchable electronic circuits

The authors would like to thank the European Commission for the financial support of the Project ... more The authors would like to thank the European Commission for the financial support of the Project STELLA, contract No. IST-028026 and the Flemish Community for the financial support of the Project BIOFLEX, contract No. SBO-040101. Special thanks to Philips Apptech for the ...

Proceedings of SPIE, Apr 21, 2006

Optical interconnections integrated on a flexible substrate combine the advantages of optical dat... more Optical interconnections integrated on a flexible substrate combine the advantages of optical data transmissions (high bandwidth, no electromagnetic disturbance, low power consumption) and those of flexible substrates (compact, ease of assembly,...). Especially the flexible character of the substrates can significantly lower the assembly cost and leads to more compact modules. Especially in automotive-, avionic-, biomedical and sensing applications there is a great potential for these flexible optical interconnections because of the increasing data-rates, increasing use of optical sensors and requirement for smaller size and weight. The research concentrates on the integration of commercially available polymer optical layers (SU-8, Truemode, Ormocer) on a flexible Polyimide film, the fabrication of waveguides and outof plane deflecting 45° mirrors, the characterization of the optical losses due to the bending of the substrate, and the fabrication of a proof-of-principal demonstrator. The resulting optical structures should be compatible with the standard fabrication of flexible printed circuit boards.

Lifetime of stretchable meander-shaped copper conductors in PDMS subjected to cyclic elongation

Stretchable conductor technology for elastic electronic systems

... Dominique Brosteaux [801001964309] - Ghent University Dominique.Brosteaux@UGent. be; M Gonzal... more ... Dominique Brosteaux [801001964309] - Ghent University Dominique.Brosteaux@UGent. be; M Gonzalez; T Loeher; D Manessis; R Heinrich; B Schmied; A Ostmann; Jan Vanfleteren [801000674512] - Ghent University Jan.Vanfleteren@UGent.be. ...

Stretchable passive matrix LED display with thin-film based interconnects

Display Week 2016, 2016

2012 4th Electronic System-Integration Technology Conference, 2012

In this contribution, results on technology developments are presented aiming to realize conforma... more In this contribution, results on technology developments are presented aiming to realize conformable electronic systems based on plastic electronics technologies. Focus of the developments is on low cost with an acceptable reliability in function of the end-application. The feasibility of this technology is demonstrated by digging into the different process steps and their characteristics. A number of demonstrators (large-area conformable illumination tiles) have been realized and are discussed. The major part of this contribution is on the mechanical characterization of these plastic electronics based technologies.

Advanced Materials Technologies, 2017

A stretchable platform with spherical‐shaped electronics based on thermoplastic polyurethane (TPU... more A stretchable platform with spherical‐shaped electronics based on thermoplastic polyurethane (TPU) is introduced for soft smart contact lenses. The low glass transition temperature of TPU, its relatively low hardness, and its proven biocompatibility (i.e., protection of exterior body wounds) fulfill the essential requirements for eye wearable devices. These requirements include optical transparency, conformal fitting, and flexibility comparable with soft contact lenses (e.g., hydrogel‐based). Moreover, the viscoelastic nature of TPU allows planar structures to be thermoformed into spherical caps with a well‐defined curvature (i.e., eye's curvature at the cornea: 9 mm). Numerical modeling and experimental validation enable fine‐tuning of the thermoforming parameters and the optimization of strain‐release patterns. Such tight control is proven necessary to achieve oxygen permeable, thin, nondevelopable, and wrinkle‐free contact lenses with integrated electronics (silicon die, radi...

SID Symposium Digest of Technical Papers, 2016

In this contribution, a conformable 64x45 RGB light-emitting diode (LED) matrix is presented. A d... more In this contribution, a conformable 64x45 RGB light-emitting diode (LED) matrix is presented. A design concept of stretchable electronics is used: non-stretchable polymer islands host rigid LEDs and are interconnected by horseshoe shaped metallic conductors, which are able to deform together with an elastomeric substrate. Thin-film metallization is used to enable a pixel pitch of 1 mm, while polyimide is used to realize the non-stretchable islands, but also to support the meandering conductors. The design of the stretchable interconnections has been optimized with respect to their mechanical and electrical performance. Thermoplastic polyurethane is introduced at a final stage of the fabrication process to ensure its compatibility with conventional thin-film processing. A passive matrix addressing scheme is used to drive the LED matrix. At a supply voltage of 10 V, the brightness of the display reaches up to 700 cd/m 2 .

MRS Proceedings, 2015

ABSTRACTA technology is presented for the production of soft and rigid circuits with an arbitrary... more ABSTRACTA technology is presented for the production of soft and rigid circuits with an arbitrary 2.5D fixed shape. The base of this technology is our proprietary technology for elastic circuits with a random shape, in which the elastic thermoset (mostly PDMS) polymer is now replaced by soft or rigid thermoplastic variants. An additional thermoforming step is required to transform the circuit from its initial flat to its final fixed 2.5D shape, but for rigid fixed shape circuits only one-time stretchability of the extensible interconnects is required, relieving the reliability requirements.

CdSe thin film transistors for the addressing of liquid crystal displays

The paper reviews the different CdSe TFT technologies of the RUGent Laboratory of Electronics. Al... more The paper reviews the different CdSe TFT technologies of the RUGent Laboratory of Electronics. All the technologies used sandwiched and doped semiconductors, self-aligned gate with respect to source-drain, standard vacuum and lithography equipment; this makes them rather simple and relatively cheap technologies. TFTs for a variety of applications are fabricated.

One-time Deformable Electronics Objective Process Flow Low cost shaped smart objects since there ... more One-time Deformable Electronics Objective Process Flow Low cost shaped smart objects since there is a growing demand for rigid free form (2.5 D or 3D) electronics circuits: Why?

Modelling Poly-CdSe TFTs for AMLCD

A model for the poly-CdSe TFT is proposed, based on recent understandings of the behaviour of pol... more A model for the poly-CdSe TFT is proposed, based on recent understandings of the behaviour of polycrystalline semiconductors. The importance of adsorbed oxygen in CdSe films and the role of donor metals is highlighted. The model also explains the formation of metal ohmic contacts on CdSe by low temperature annealing.

Silicon oxynitride layers for device passivation

The process optimization of PCVD silicon oxynitride (SiON) dielectric layers is described. The of... more The process optimization of PCVD silicon oxynitride (SiON) dielectric layers is described. The often large mechanical stress in such films is a drawback for large area applications. By using Taguchi's methodology for the process optimization, a 4 mum thick, pinhole-free SiON layer could be deposited, with practically no mechanical stress.

Physica Status Solidi a-Applied Research, 1994

A number of interesting transient phenomena, occurring in CdSe: C u : CI thin films, exhibiting s... more A number of interesting transient phenomena, occurring in CdSe: C u : CI thin films, exhibiting superlinear photoconductivity, are described: the typical S-shaped current rise, the exponential decay, the inversely proportional dependence of rise time on illumination level, the illumination independent decay time, the influence of bias illumination and pulse frequency on the current rise and decay curves, and the possibility to influence the rise and decay time through the application of a potential to a field-plate. A simple, analytical model for these transients, based on the crude two-level model for superlinear photoconductors, is developed. The model explains the observed behaviour qualitatively and, to a certain degree, even quantitatively. Using this model, the value of the electron capture cross section of the sensitizing centres is estimated from the experimental results. The resulting value of 1.9 x 10l 9 cm2 falls in the range of the values reported elsewhere. Im folgenden werden fur CdSe : Cu : C1-Dunnschichten, die superlineare Photoleitfiihigkeit aufweisen, einige interessante transiente Erscheinungen beschrieben: typischer S-formiger Stromanstieg, exponentielles Abklingen, weiterhin umgekehrt proportionales Verhalten der Anstiegszeit zur Beleuchtungsstiirke und die hiervon unabhiingige Abklingzeit, EinfluR von Bias-Belichtung und Pulsfrequenz auf Stromanstiegs-und Abklingkurven, sowie die Moglichkeit, die Anstiegs-und Abklingzeiten mit Hilfe einer Feldeffektelektrode zu beeinflussen. Ein einfaches, analytisches Modell, das sich auf das einfache Zwei-Niveau-Modell fur superlineare Photoleitfiihigkeit stutzt, und das in der Lage ist, das beobachtete transiente Verhalten nicht nur qualitativ, sondern his zu einem gewissen Grade auch quantitativ, zu beschreiben, wird aufgestellt. Damit kann aus den experimentellen Ergebnissen die GroRe des Elektronenwirkungsquerschnitts fur die lichtempfindlichen Zentren abgeschatzt werden. Der hierfur erhaltene Wert von 1,9 x 10l 9 cmz entspricht durchaus dem in der Literatur angegebenen Wertebereich.

Japanese Journal of Applied Physics, 2013

Conformable electronics, i.e., electronics that can be applied on curved surfaces, is demanded no... more Conformable electronics, i.e., electronics that can be applied on curved surfaces, is demanded nowadays in place of conventional rigid printed circuit board (PCB) based electronics for a number of applications. In the field of stretchable electronics there has been a swift progress in recent years. In this paper we are presenting our contribution to this ever growing topic, including thin-film based polyimide (PI), supported Au stretchable meanders as well as PCB based Cu meanders. These meanders are supported by PI or poly(ethylene naphthalate)/poly(ethylene terephthalate) (PEN/PET) films. Thin-film based stretchable interconnects is targeting mainly the biocompatible environments with demands for strong miniaturization while the PCB based technology is used more for large area applications. Both approaches are reviewed in this paper in terms of fabrication processes, materials and cyclic fatigue reliability. For each technology fabricated demonstrators are presented as well.

Ultra-thin chip package using embedding in spin-on polyimides

Ga onmiddellijk naar paginanavigatie. As of July 1st 2010, only records submitted with full text ... more Ga onmiddellijk naar paginanavigatie. As of July 1st 2010, only records submitted with full text will be accepted in the academic bibliography. more info. Error: You do not have the rights to download this document. Paginanavigatie. ...