Direct‐Write Printing of Multicolor Electroluminescent Films for Stretchable Display

Etching belongs to an ancient creative art of Europe, and it originated gold silversmith printing process in European. Copper plate has a certain strength, through the copperplate etching and release agent transfer printing plate making, printing on linen, you can get the printing design creative nature. Etchings of transfer printing on linen, provided a feasibility scheme of flax printing DIY accessories and haute couture.

In order to rival the quality of silver halide photographs, digital printing systems need to satisfy issues of high print quality as well as image stability. Our research and development efforts have focused on thermal dye transfer and ink jet printing systems, with extraordinarily good results in each system.Discussion will focus on the chelate reaction between dye molecules and metal ions in the thermal dye transfer printing system, which has greatly improved the image stability issues, well in excess of original targets.As for ink jet printing, attention was paid to improving the print quality. These efforts led to the world's first production of micro porous printing media with an RC-paper base. The combination of the printing media and dye inks brings the expected print quality together with other features such as quick drying cased by high ink-absorption speed, resistance to water.Work on improving image stability in ink jet systems will also be discussed.

Microscopic optical image density and resolution performance are discussed for laser thermal transfer printing of the dye sublimation type. This printing method provides high resolution because of the high converging property of the laser beam. In this study, optical density profiles of line images printed by dye sublimation type laser thermal transfer printing were measured and compared with images of the wax type in order to clarify the spread of the printed dots. These profiles were explained numerically, using tone reproduction curves. Resolution performance was evaluated, quantitatively, and the maximum resolution was found to be 10,160 dpi. This value was confirmed by the printed microcharacters. Laser dye transfer printing is feasible for printing not only full-color images, but also fine patterns and microcharacters.

In this paper, we present a novel sensor array manufacturing process that involves transfer printing methods using a chip mounter with a vacuum collet. Using these methods, one can mount not only ultra-thin microsensors but also microcontroller and amplifier chips required for sensor device fabrication. We successfully transfer-printed a very fragile microelectromechanical systems-based 5-mm-long, 1-mm-wide, 5- $\mu \text{m}$ -thick high-aspect-ratio ultra-thin Pb(Zr, Ti)O3 (PZT) (1.9 $\mu \text{m}$ )/Si (3 $\mu \text{m}$ ) strain sensor onto a flexible printed-circuit (FPC) substrate with etched Cu wiring. Then, we connected the sensor to the wiring by printing a conductive paste using a screen printer. Large ferroelectric polarization–voltage hysteresis curves were obtained even after the transfer printing process. Since an output voltage corresponding to the magnitude of the strain from the developed sensor was generated, it was confirmed that ultra-thin sensors could be integrated to the FPC substrate by these transfer and screen printing techniques without damage. The PZT thin films have shown 0.18 mV/ $\mu \varepsilon $ of dynamic strain sensitivity according to the resonant vibration of the stainless plate.

Different electronic devices are ubiquitous in our daily lives. These devices keep on improving daily, and their evolution contributes to the enrichment of our lives. However, two factors remain, that is, little or no progress at all has been introduced in the field of electronics for a long time. First, the use of a printed circuit board (PCB) to drive electronic-device circuits has not been improved. The PCB remains thick and hard. Second, the PCB is enclosed in a cabinet for finished products. Generally, device engineers and product designers design electronic circuits and cabinets, respectively. In this case, engineers emphasize that they cannot change the circuit size and arrangement of the lead-out wiring, whereas designers insist that they must realize an attractive cabinet beyond the restriction of the circuit designs.To overcome this issue, conformal printing using a soft blanket has attracted much attention as a technique that can form wires/electrodes on objects with complex shapes. Although the cabinets of electronic devices often have a curved surface, printing that uses a soft blanket can simply and easily form patterns on these electronic devices. At least, wires/electrodes can be formed on a cabinet with a complex shape. Among the many printing methods, the screen-printing-based technology is the most practical. The wires/electrodes of various commercially available electronic devices are fabricated using this printing method. Thus, we are developing screen-printing-based conformal-printing techniques such as screen-offset and screen-pad printing.Screen-offset printing involves screen printing onto a blanket made of silicone and transfer printing from the blanket to a substrate [Fig. 1(a)]. In this process, the organic solvents in conductive ink are absorbed by the silicone. Therefore, collapse of the patterns due to cohesion failure during transfer printing can be prevented. In addition, solvent absorption prevents ink from smudging caused by its fluidity, which subsequently means that fine patterns can be formed compared with those obtained using the conventional screen printing. The width of the patterns formed by screen-offset printing can be as fine as 10 µm, whereas the minimum width obtained by screen printing in mass-produced products is approximately 40–50 µm.Furthermore, the surface free-energy of silicone is low, indicating that screen-offset printing can form patterns even on an adhesive. For example, a material sticks to a screen mask when conventional screen printing is employed. Although heat-applied soldering is often employed for electronic-component mounting, non-heated interconnection can be performed by fixing the electronic components on a screen-offset-printed adhesive substrate using an alignment of component and substrate electrodes.Another feature of the screen-offset printing is that the silicone blanket can deform along the shape of a substrate owing to its softness, which indicates that the conductive ink can be transcriptionally formed on the surface of an object with a complex shape. For example, we developed printed wire-bonding techniques using screen-offset printing [Fig. 1(b)]. A 200-µm-thick Si chip with face-up-type electrodes was arranged on a PCB. Using screen-offset printing, the conductive-ink patterns could climb over the cleaved sidewall of the Si chip because silicone can deform along the steric structure. Thus, wiring connections between the PCB pads and Si-chip pads were successfully performed.Furthermore, screen-offset printing can properly form conductive patterns on textiles [Fig. 1(c)]. For example, plain-woven cotton, which is often used for clothes such as shirts, has a bumpy and porous surface, implying that forming wires/electrodes without breaking is very difficult. However, the silicone blanket can deform along the textured surface. In addition, dried ink caused by organic-solvent absorption of the blanket can bridge the air gap. This wiring technique can contribute to the e-textile technology as a platform for wearable electronics.Applying screen-offset printing on a surface with a large step on the order of millimeters is difficult. To overcome this problem, we need to employ a much softer and thicker blanket to drastically deform along the substrate surface. In contrast, screen printing ink onto such a softer blanket becomes difficult. To address this issue, we have developed screen-pad printing, which is composed of the following: (i) screen printing to a normal blanket, (ii) picking ink to a soft pad from the blanket, and (iii) transcriptionally forming ink patterns on a substrate from the pad. Patterns can be formed even on bumpy surfaces with a large step owing to the soft pad, although the number of processes increases.Common objects generally do not have a flat surface but have a complicated shape. We are currently attempting to fabricate such object-sensor devices by forming functional-material patterns using our developed conformal-printing technique. Figure 1

The printing method of the thermal transfer printer is to push an ink ribbon that is heated and melted by a thermal head to a printing paper, and transfer the ink to desired positions on the paper. If the heating by the thermal head is not sufficient, the ink cannot be melted and cannot be transferred to the paper. Moreover, even if the heating is excessive, a high quality print cannot be done, because an excess amount of ink will be transferred to the paper. The heat generated by the thermal head is transmitted to the printing paper through the ink ribbon. Thus the thermal conductivity of the printing paper affects the temperature rise of the ribbon and as a result printing quality. The thermal conductivity of the paper is commonly measured with a quick thermal conductivity meter. However the printing paper is too thin for the measurement. A new method of evaluating the thermal conductivity of the printing paper using the thermal transfer printer was proposed.

This work describes a facile thermal transfer printing process for solution‐processed high‐quality ZnO nanostructures. Nanostructures are synthesized through patterned solution growth and transfer‐printed onto a polymer substrate with an inverted configuration. Thus, the shape of the solution‐processed ZnO nanostructures can be regulated to have diversified forms, clearly defined edges, and improved surface profiles. To further demonstrate the scalability of such transfer printing process, a metasurface color filter with 300 µm × 500 µm “windmill” pattern is designed and more than 300 000 nanorod units included. After the structures are transferred, the color filter can be gradually tuned by O2 plasma treatment. Moreover, the uneven height of as‐synthesized nanorods with different diameters can be evenly rescaled, implying a precise control over the vertical dimension. Lastly, an ultra‐high transfer accuracy is validated with a lateral displacement of less than 7 nm. The presented work demonstrates a facile and low‐cost transfer printing route toward ZnO‐based metasurfaces on flexible substrates.

Currently rainbow and volume holograms are the most used protective holograms. The production technology of such holograms allows to replicate them at the industrial level without deteriorating their protective properties. However, new methods of obtaining protective holograms have been recently studied. Previously has been repeatedly demonstrated the possibility of applying computer-generated Fourier holograms (CGHs) to scattering, non-photosensitive media. We want to study the possibilities of obtaining Fourier holograms on such media and discover protective properties of such holograms. We consider the possibility to obtain binary and halftone CGHs on various mediums in mass-production, including metallized films, self-adhesive labels on paper basis, paper and laser film. For the application we used technologies of thermal transfer and laser printing, as well as direct laser recording. The reconstruction was carried out both optically and using a smartphone. This paper presents experiments and results of mass-production holograms on the selected mediums. We have simulated the distortions that may occur after manufacturing of CGHs, analyzed the quality of the image being reconstructed under various application methods. We show that such holograms can be used as security elements in specific cases. Still, there are the possibilities of improving the quality of deposition of protective hologram elements depending on the used technology, as well as the possibility of taking into account potential distortions during the synthesis of holograms.

Most methods of depositing perovskite films cannot meet the diverse requirements of real applications such as depositing films on various types of substrates, making patterns with different bandgaps for full-color display. Here, a robust mass transfer method of perovskite films and nanostructures is reported, meeting those requirements, by using an ultrathin branched polyethylenimine as interfacial chemical bonding layers. The transfer-printed perovskite films exhibit comparable morphology, composition, optoelectronic properties, and device performances with the counterparts made by optimized spin-coating methods. The perovskite light-emitting diodes (PeLEDs) using the transfer-printed films show decent external quantum efficiencies of 10.5% and 6.7% for red (680nm) and sky-blue (493nm) emissions, which are similar to the devices made by spin-coating. This robust transfer printing method also enables the the preparation of perovskite micropatterns with a high resolution up to 1270 pixels per inch. Horizontally aligned red and sky-blue perovskite microstripes are further obtained through multiple printing processes for white PeLEDs. This work demonstrates a feasible strategy for making perovskite films or micropatterns on various substrates for real applications in full-color display, white LEDs, lasing, etc.

A new class of printing strategies is described for the manufacture of microstructures and nanostructures. This class collectively is referred to as molecular transfer lithography (MxL). The approach is based on the room-temperature fabrication of water-soluble polymer templates by spin casting a polyvinyl alcohol film-forming solution to replicate surface patterns. The templates are useful not only for pattern formation, but also for materials transfer printing, employing a low-cost, convenient, biocompatible chemical approach to high-resolution processing. Results are provided to demonstrate deep submicrometer feature sizes of holes, pillars and lines, 3-D patterns, materials transfer printing of metallic thin films, planarization of wafer topography, and water-soluble polymer templates for 100- and 200-mm wafer patterning. The alignment tooling is discussed and it is shown that MxL can be adapted for use on standard contact aligners with a replacement of the quartz photomask with a water-soluble polymer template to improve resolution without a change of equipment. A high-throughput alignment system for MxL is also discussed. The MxL class of pattern formation and materials transfer printing strategies is differentiated with respect to imprint lithography and soft lithography methods.

Transfer printing, a foundational manufacturing route for integrating heterogeneous materials onto diverse substrates, holds great promise for applications in flexible electronics, emerging displays, and soft robotics. As applications grow more complex, the quality of ultrathin films integrated onto applicable substrates, initially fabricated on rigid substrates by spin-coating, physical vapor deposition, or chemical vapor deposition [e.g., photoresists, metals, two-dimensional (2D) materials] with thicknesses below 10 μm, becomes critical to the performance of advanced devices, including flexible/curved electronics and 2D films-based electronics. However, achieving damage-free transfer printing of ultrathin films requires resolving the trade-off in traditional methods between interfacial fracture and in-plane film damage. Herein, this review elucidates the principles underlying damage-free transfer printing of ultrathin films, highlights recent innovations that enable on-demand control of interfacial adhesion during the process, and summarizes typical applications based on transferred damage-free films. Finally, we provide perspectives on the remaining challenges and future developments needed to enable industrial-scale manufacturing and inspire continued innovation.

Wydawnictwo SIGMA-NOT wydaje czasopisma fachowe informujące swoich czytelników o najnowszych osiągnięciach naukowych i nowoczesnych rozwiązaniach technicznych w Polsce i na świecie, popularyzuje problemy techniczne oraz poszerza wiedzę i kulturę techniczną.

1.Introduction Solid oxide fuel cells (SOFCs) have received much attention as promising electrochemical power generation devices because of their high electrical efficiency and environment adaptability. Development of SOFCs is now focused on lowering the operating temperature from the conventional range of 750-900°C to an intermediate range of 500-700ºC, allowing a wider range of materials for SOFC components and improvement of thermal reliability. Preparing the Yttlia Stabilized Zirconia (YSZ) and Gadolinia-doped ceria (GDC)) bilayer electrolytes are effective for reducing operating temperature [1]. In the present work, NiO-YSZ anode supported cells with YSZ/GDC bilayer electrolytes and (La,Sr) (Co,Fe) O3 (LSCF) thin film cathodes were fabricated by pulsed laser deposition (PLD) and screen printing. However, one thermal cycle test of a cell between 200°C and 600°C, with heating and cooling rates of 400°C /h, resulted in detachment of the LSCF thin film and thus reduced durability. To improve the adhesion between the LSCF and GDC, (La,Sr)CoO3(LSC), nano particles were deposited on the GDC thin films by PLD. This step was expected to increase contact area between electrolyte and cathode. We investigated the influence of the LSC nano particle on thermal reliability and I-V characteristic of SOFCs. 2.Experimental Details NiO-YSZ cermet (NiO:YSZ＝60:40 wt%, 500 μm thick) was used as the anode substrate, YSZ (8 mol% Y2O3) and GDC (10 mol% GdO2) as electrolyte materials, and La0.6Sr0.4Co0.2Fe0.8 (LSCF) and La0.6Sr0.4Co (LSC) as cathode materials. YSZ (8 μm thick) and LSCF (30 μm thick) films were prepared by screen printing and GDC (3 μm thick) was deposited by PLD. Two sets of unit cells were prepared: one set was with LSC nano particles deposited between GDC and LSCF thin films by PLD (NiO-YSZ / YSZ / GDC / LSC particle / LSCF) and the other set was without LSC nano particles (NiO-YSZ / YSZ / GDC / LSCF).Thermal cycle test between 200 and 600°C with heating and cooling rates of 400° C /h were performed. Power densities and I-V characteristics were measured. 3.Results (a) Deposition of LSC nano particles by PLD on the GDC thin film. Figure 1 shows a scanning electron microscopy image of the surface of a GDC thin film. Many LSC nano particles (50-nm diameter) were deposited on the dense GDC thin film by PLD, which increased the area of contact between the GDC and LSCF thin films. (b) Thermal cycle test of NiO-YSZ anode supported cells with or without LSC nano particles. Two types of unit cells, (1) NiO-YSZ / YSZ / GDC / LSC particle / LSCF and (2) NiO-YSZ / YSZ / GDC / LSCF were prepared by screen printing and PLD. Photographs of unit cells after one thermal cycle are shown in Fig. 2. It is evident that adding the LSC nano particles succeeded in suppressing detachment of the LSCF thin film. Spike effect resulted in high adhesion between LSCF and GDC. The unit cell with LSC nano particles survived 50 thermal cycles and yielded higher thermal reliability. (c) I-V characteristics of NiO-YSZ anode supported cells with or without LSC nano particles. Figure 3 shows the I-V characteristics of unit cells with and without LSC nano particles. The maximum power densities of unit cells with or without LSC nano particles were 0.5 and 0.3 W·cm-2, respectively. Cell performances were found to be better when LSC nano particles were deposited, because of increase in reactive sites.[1] T. Mukai et al., Journal of Fuel Cell Science and Technology , 10(2013) 061006-1-6.

We have developed a novel software package which is able to simulate the performance parameters of the solar cells based on diffusion process parameters as well as finger-bus design parameters. An algorithm for computer aided design (CAD) incorporated in this software package is useful for designing and optimizing the finger-bus dimension for optimum solar energy harvesting. The CAD algorithm of this software package can save the optimized finger-bus design in a .dxf format which can then be directly used as layout for mask making of the metallization layers using screen printing, CMOS based lithography or e-beam writer. The .dxf format file generated by our software package can also be viewed using other CAD softwares such as AutoCAD, L-Edit, etc. This software package also simulate the sheet resistivity of the doped poly-silicon layer based on the process parameters — POCl 3 diffusion temperature, duration of POCl 3 diffusion reaction, annealing temperature and annealing duration. This research paper presents the new algorithm incorporated in the novel software as discussed above as well as the optimization of the process parameters and finger-bus design.

This report summarizes the results of Phase II of this program, 'Low-Cost Manufacturing Of Multilayer Ceramic Fuel Cells'. The objective of the program is to develop advanced ceramic manufacturing technologies for making planar solid oxide fuel cell (SOFC) components that are more economical and reliable for a variety of applications. Phase II development work focused on three distinct manufacturing approaches (or tracks) for planar solid oxide fuel cell elements. Two development tracks, led by NexTech Materials and Oak Ridge National Laboratory, involved co-sintering of planar SOFC elements of cathode-supported and anode-supported variations. A third development track, led by the University of Missouri-Rolla, focused on a revolutionary approach for reducing operating temperature of SOFCs by using spin-coating to deposit ultra-thin, nano-crystalline YSZ electrolyte films. The work in Phase II was supported by characterization work at Ohio State University. The primary technical accomplishments within each of the three development tracks are summarized. Track 1--NexTech's targeted manufacturing process for planar SOFC elements involves tape casting of porous electrode substrates, colloidal-spray deposition of YSZ electrolyte films, co-sintering of bi-layer elements, and screen printing of opposite electrode coatings. The bulk of NexTech's work focused on making cathode-supported elements, although the processes developed at NexTech also were applied to the fabrication of anode-supported cells. Primary accomplishments within this track are summarized below: (1) Scale up of lanthanum strontium manganite (LSM) cathode powder production process; (2) Development and scale-up of tape casting methods for cathode and anode substrates; (3) Development of automated ultrasonic-spray process for depositing YSZ films; (4) Successful co-sintering of flat bi-layer elements (both cathode and anode supported); (5) Development of anode and cathode screen-printing processes; and (6) Demonstration of novel processes for composite cathode and cermet anode materials. Track 2--ORNL's development work focused solely on making anode-supported planar cells by tape casting of a porous anode substrate, screen printing of a YSZ electrolyte film, co-sintering of the bi-layer element, and screen-printing of an opposite cathode coating. Primary accomplishments within this track are summarized below: (1) Development and scale-up of anode tape casting and lamination processes; (2) Development of proprietary ink vehicle for screen-printing processes; (3) Development of screen-printing process for depositing YSZ films; (4) Successful co-sintering of flat bi-layer anode-supported elements; and (5) Development of cathode screen-printing process. Track 3--UMR's process development work involved fabrication of a micro-porous cathode substrate, deposition of a nano-porous interlayer film, deposition of nano-crystalline YSZ electrolyte films from polymeric precursor solutions, and deposition of an anode coating. Primary accomplishments within this track are summarized below: (1) Development and scale up of tape casting and sintering methods for cathode substrates; (2) Deposition of nano-porous ceria interlayer films on cathode substrates; (3) Successful deposition of dense YSZ films on porous cathode substrates; and (4) Identification of several anode material options.