Gas response behaviour and photochemistry of borondiketonate in acrylic polymer matrices for sensing applications

High resolution patterning for flexible electronics via roll-to-roll nanoimprint lithography

Investigation of the effects of LIFT printing with a KrF-excimer laser on thermally sensitive electrically conductive adhesives

Laser induced forward transfer is an emerging material deposition technology. We investigated the feasibility of this technique for printing thermally sensitive, electrically conductive adhesives with and without using an intermediate dynamic release layer. A 248nm KrF-excimer laser was used to print the epoxy-based conductive adhesives...

Excimer laser patterning of PEDOT-PSS thin-films on flexible barrier foils: A surface analysis study

Selective laser patterning of thin organic films is an important aspect in the roll-to-roll production of organic electronic devices such as organic light emitting diodes (OLEDs). An excimer laser is well suited for the patterning and structuring of polymer thin films as their UV absorption is significant. Selective removal of a transparent...

Full color flexible top-emission AMOLED display on polyethylene naphthalate (PEN) foil with metal oxide TFTs backplane

We have developed a full color flexible top-emission AMOLED display with 80 ppi resolution using In-Ga-Zn-O TFT backplane on PEN foil under the maximum process temperature of 150 oC. Notwithstanding the low processing temperature, the TFTs with SiOx passivation layer show high reliability with VTH shift of less than 0.2 V at 10,000 seconds under...

Micromechanical modelling of short-term and long-term large-strain behaviour of polyethylene terephthalate

A micromechanically based model is used to describe the mechanical behaviour of polyethylene terephthalate (PET) under uniaxial compression up to large strains and at different temperatures. The creep behaviour of isotropic PET is simulated and compared to experimental data to demonstrate the applicability of the model to describe the long-term...

Low-temperature IGZO TFT backplane and its application in flexible AMOLED displays on ultrathin polymer films

We present a low-temperature metal oxide transistor backplane technology using PECVD dielectrics. We show successful integration of the backplane in flexible 200ppi AMOLED displays on ultrathin polymer films. The displays are encapsulated with a thin-film barrier and the total stack thickness is less than 150μm.

Single layer broadband anti-reflective coatings for plastic substrates produced by full wafer and roll-to-roll step-and-flash nano-imprint lithography

Anti-reflective coatings (ARCs) are used to lower the reflection of light on the surface of a substrate. Here, we demonstrate that the two main drawbacks of moth eye-structured ARCs-i.e., the lack of suitable coating materials and a process for large area, high volume applications-can be largely eliminated, paving the way for cost-efficient and...

Fabrication of transistors on flexible substrates: From mass-printing to high-resolution alternative lithography strategies

In this report, the development of conventional, mass-printing strategies into high-resolution, alternative patterning techniques is reviewed with the focus on large-area patterning of flexible thin-film transistors (TFTs) for display applications. In the first part, conventional and digital printing techniques are introduced and categorized as...

Flexible AMOLED display on polyethylene napthalate (PEN) foil with metal-oxide TFT backplane

We present a top emitting monochrome AMOLED display with 85dpi resolution using an amorphous Indium-Gallium-Zinc-Oxide (IGZO) TFT backplane on PEN-foil. Maximum processing temperature was limited to 150 °C in order to ensure an overlay accuracy < 3μm on PEN foil. The backplane process flow is based on a 7 mask photolithography process that...

Hygroscopic and thermal micro deformations of plastic substrates for flexible electronics using digital image correlation

Thin polymer substrates are promising materials for flexible electronics with many advantages. However, the dimensional stability of polymer substrates is low. Nowadays, this is overcome by laminating polymer substrates onto a rigid carrier. Nevertheless, carrier-less processing will be a foreseen next step for future manufacturing of plastic...

Flexible electronics: Prediction of substrate deformation during different steps of the lithography process

A numerical model was developed to simulate the micro-deformations of a polymeric substrate due to lithographic processing of different layers of a transistor-like structure. The results of the model were validated with the results from experiments. The model, a mechanical-thermal-hygroscopic model, takes into account the dimensional effects of...

Double-layer imprint lithography on wafers and foils from the submicrometer to the millimeter scale

In this paper, a thermal imprint technique, double-layer nanoimprint lithography (dlNIL), is introduced, allowing complete filling of features in the dimensional range of submicrometer to millimeter. The imprinting and filling quality of dlNIL was studied on Si substrates as a model system and compared to results obtained with regular NIL (NIL)...

Hygroscopic and thermal micro deformations of plastic substrates for flexible electronics using digital image correlation

Thin polymer substrates are promising materials for flexible electronics with many advantages. However, the dimensional stability of polymer substrates is low. Nowadays, this is overcome by laminating polymer substrates onto a rigid carrier. Nevertheless, carrier-less processing will be a foreseen next step for future manufacturing of plastic...

Fracture mechanisms in biopolymer films using coupling of mechanical analysis and high speed visualization technique

The aim of this study was to provide a detailed description of the fracture mechanisms in three different biopolymer thin materials: gelatin, hydroxypropyl cellulose (HPC) and cassava starch films. That was achieved by using a combination of fracture mechanics methodology and in situ visualization with high speed imaging technique. By analyzing...

Modeling the residual shrinkage during lithographic processing on flexible polymer substrates

The challenge of lithographic production of electronic circuitry on polymer foil is that deformations approaching the feature sizes of the circuitry can cause considerable overlay problems and thereby malfunctioning of the devices. The substrate foil is susceptible to several types of deformations. Accurate prediction of these deformations is of...

Polymer substrates for flexible electronics: Achievements and challenges

Flexible electronics technology can potentially result in many compelling applications not satisfied by the rigid Si-based conventional electronics. Commercially available foils such as polyethylene terephthalate (PET) and polyethylene naphthalate (PEN) have emerged as the most suitable polymer materials for wide range of flexible electronics...

Prediction of the thermo-mechanical material behavior of PEN foil during photolithographic processing

Flexible substrates (polymers) for plastic electronic products are far less stable to environmental factors, like heat and moisture, than currently used non-flexible substrates (silicon). This introduces problems during the lithography process of these products. This study presents a thermo-mechanical model of PEN foil; an organic material often...