Toppan Inc earlier in the year reported that it has developed an IGZO TFT technology able to withstand >1M bending cycles @1mm radius. This is an incredible result (for reference: foldable smart phone has a radius of 3mm). This is a fantastic result. Manabu Ito discussed at a TechBlick conference how this was achieved. Here, we offer a summary of the key technical innovations. 1) Make dielectric organic: In general many have focused on organic semiconductors to promote bendability of TFT arrays. However, the active channel is an oder of magnitute thinner than the dielectric, and thus has a far less important influence on bendability. In this work, Toppan switched to an organic gate insulator and etch stopper material (PVP based??) instead of the glassic SiOx, SiNx or AlOx materials. 2) Plasma resist layer: As shown in the slide below, the deposition of the IGZO layer directly on the organic dielectric (botton gate device architecture) damages the surface, thus leading to very poor TFT charactersitics with low mobility, limited on/off ratio, higher threshold voltage, and poor sub-threshold characteristics. To overcome this, Ito-san et al deposited a just 7nm thin SiOx layer using ALD. This layer helps improve interfacial properties and also protects the underlying organic dielectric layer during the position. Indeed, as shown below, this results in excellent transfer characteristics for the TFT! 3) Island approach: The 7nm-thin SiO2 layer however cracked after 100k cycles ...

Here you can see data - shared at TechBlick in March 2022- that shows rapid sintred Cu nanoparticles are a viable solution that meet most industry requirements. First some background: the PV industry has tremendously progressed with a steep learning curve of 25%, meaning the cost drops 25% everytime the accumulated production capacity doubles.
The PV industry itself is now very large (around 183 Gwp in 2021 of new and replacement installation) but how large will it get in a net zero emission scenario in 2050? There will need to be an installed capacity of 20-80 TWp, producing 30-100 PWh of electricity. This will translate into an annual volume of 1-4 TWp/year, showing that there is still much room for expansion and thus innovation Ag is a major cost driver of the PV cell today. Around 15mg/Wp is used in a PERC architecture for bus and finger metallization. Interestingly, not just cost but also availability can be a concern since 50% of today's world mining capacity would only cater for 1 TWp/a. Given these concerns, the industry has long sought to replace Ag with alternatives such as Cu. However, many issues havehindered adoption even in new PV architectures including Cu diffusion into Si, solderability, good adhesion, long term stability, etc etc
In this study, Jan Lossen from ISC Konstanz shows that one can meet almost all requirements on a back-contact Si PV when the bus bars are screen printed using Cu nanoparticle pastes from Copprint. It also shows the good outlook fo...

Wearable electronic textiles are a demanding environment for reliable interconnects – the ability to function with movement and survive multiple cleanings and reuse. Good adhesion is particularly challenging in these wearable and conformable electronics applications. While solders provide the most conductive electrical connection, they are rigid and require not only the addition of an underfill adhesive but usually a post bond encapsulation. SunRay Scientific’s ZTACH® ACE, Anisotropic Conductive Epoxy, provides reliable interconnections between electronic components and circuitry on textiles with excellent structural bonding, without encapsulation, even under repeated stretching and washings. ZTACH® ACE has been shown as a scalable assembly process for e-Textile manufacturing in an SMT line. Video of resistors, voltage regulators and LEDs applied to stretchable conductive silver and carbon inks, printed on TPU, with no encapsulation, going through extreme stress and easily surviving to remain functional Anisotropic electrically conductive adhesive compatible with automated SMT Processing ZTACH® ACE, an Anisotropic Conductive Epoxy, allows for simultaneous Z-axis connections of all the devices on a board, sheet or fabric, across large formats. It requires no patterning, no bonding pressure, and can be cured at low temperatures. ZTACH® ACE can adhere to a wide range of substrates, including PET, TPU, various textiles and PCBs. This material acts as its own underfill, pro...

Electrochromic technology enables layers that can change color or become transparent using an electrical current. Compared to other color-changing technologies such as photochromism and thermochromism, electrochromic devices can be perfectly controlled to achieve the desired transparency at any time. While the technology has been discovered almost 50 years ago, only recently have commercial applications emerged, mainly in electrochromic glass for automotive rearview mirrors and airplane windows. A large potential market for electrochromic devices is in smart windows, where they show promise to save energy. The building sector accounts for over 50% of greenhouse gases produced annually, and building operations, including heating and cooling, account for close to 30% of this number (source: 2021 Global Status ABC Report). Using electrochromic devices, it is possible to implement energy-saving control strategies that beat any other glazing with static optical properties. However, the main challenge remaining to having this technology becoming more widespread is the high cost of electrochromic modules. Brilliant Electrochromic Materials Seeing this market challenge, we saw an opportunity for using our organic semiconductors (OSCs) to create a line of products dedicated to electrochromic devices. As OSCs can be modified, it is possible to devise them to be easy to formulate into inks, which opens cost-effective manufacturing from simple printing techniques on rigid (ex: glass) or...

There are many ranging underwater sound detection to vital signs monitoring to micrphones. In this short video, Mickaël Pruvost, PhD from Piezotech, Arkema Group showcases a breadth of applications. But first some background: Piezotech has two types of materials 1) P(VDF-co-TrFE) is a interested fluorinated copolymer able to convert mechanical demonstrations into transient electrical signals and vice versa. It is also sensitive to temperature variations through the pyroelectric effect. It can thus act as an excellent transducer of motion - from body motion to acoustic waves- into electrical signals 2) The terpolymer versions (P(VDF-TrFE-CFE/CTFE) are ale to also convert electrical signals into large deformation via the electrostriction effect. Here, larger movements can be produced compared to the co-polymer versions, and so this is better suited to actuation applications. These materials are produced as powders which are then formulated into printable inks. The inks will need to sandiwched with two conductive (Ag, PEDOT, etc) electrodes and are then annealed and (in the case of FC coplymers) poled to produce piezoelectric properties These materials are thus able to produce flexible, thin sensors and actuators on a variety of substrates printed into arbitary shapes. They are very robust. For example, they survive 1000hrs @105C and 85%RH, do not degrade under hot water test (one hour under 99,9C), and withstand thermal shock test (30min @-40C followed by +85C for 11 days!). F...

Sometimes manufacturers would like to install heating in objects that are difficult to heat.
The armrest of your car. Your sporty winter coat. Bags for food delivery. Sleeping bags. All of these are products that are usually influenced by environmental temperature and cannot autonomously create their own level of temperature. Until now. Imagine a fast pleasant temperature in your vehicle, not just coming from your seatback, but also from the side panel, steering wheel or armrest. Think of immediately defrosted mirrors and sensor de-icing that make it safer to drive off right away.
Picture a more comfortable dentist appointment because the dentist chair is pleasantly warm. Preheated surgical tables and drapes, pet clothing, baby strollers, a warm rug in your dining room… a lot of objects can create a more satisfying experience when generating heat at once. PTC heaters make all these applications, and many more, possible today. Positive Temperature Coefficient heaters or PTC heaters are electrical resistance heaters whose resistance increases with temperature. If a constant voltage is applied, the heater produces a large amount of heat when its temperature is low and a smaller amount of heat when the temperature rises, until it reaches its peak level or equilibrium point, at which the temperature stays relatively stable. PTC Effect Curve ©Henkel PTC heaters are created by printing conductive ink on a flexible substrate. At first silver is printed as a busbar to conduct curre...

Speaker: Bryan Germann | Company: Optomec | Date: 10-11 March 2021 | Full Presentation Microwave & RF devices generally are not small, cheap or lightweight. Printed electronics has an opportunity to change this stigma, enabling the creation of smaller, lower mass, cheaper and in some cases higher performance devices than current manufacturing methodologies. Enabling unique & even mainstream applications in field of defense, automotive and even consumer grade electronic devices to advance. Optomec’s Bryan Germann will share details of device geometries, characterized performance as well as materials information and reliability data in order to showcase the success of using Optomec’s Aerosol Jet printed electronics platform for developing all manner of RF devices and structures for real world applications. Primary applications will include printed 3D RF microwave circuit elements, 3D & 2.5DIC chip interconnect methodologies, even some 3D conformal, multi-layered circuitry over complex surfaces for Optomec customers. Bryan Germann Product Manager @ Optomec Bio Optomec’s Aerosol Jet technology has a unique solution to enable panel front to backside connections without glass vias or vacuum processes. Aerosol Jet’s ability to print at high resolution, down to 10 μm, and at a high aspect ratio, as high as 5mm from the substrate regardless of topology, make it the ideal solution for both manufacturing and repair of metallization on glass edges. Demonstration of high speed, high densi...

The three themes are closely linked since QDs can be digitally printed as color conversation materials atop blue microLEDs to enable wide color gamut RGB uLED displays without requiring a separate transfer step for each color. Join TechBlick's event on microLEDs to learn more https://lnkd.in/eDRi5kp2 Inkjet is the common technology investigated for such a purpose. As shown below by Prof.Armin Wedel, however, its 4pL droplet is too large, allowing at best a 40um pixel and not able to reach even 850 dpi Electrohydrodynamic printing (EHD) can however address this issue. In EHD, the droplets are pulled out by an electric field from a nozzle which sits close (50um or so) to the surface and thus requires a good printing facility. As shown below, the droplet volume is only 0.5pL, enabling 1-10um pixels in the lab and 15um reproducibly. This will enable one to achieve 850ppi and 1000ppi! Slide 2 shows an example of a QD color filter (QD-CF) for a microLED display deposited using EHDJet. Here, 15um pitch is reported, achieving 1000ppi. The roadmap will be to evolve the technology towards even 2000ppi! These are excellent advacements of the art and technology, paving the way for the development of high-PPI microLED technology Of course, EHDJet is a relatively new technology. It is mainly single head and slow, although multi-head print heads are emerging. Nonetheless, it is an elegant solution for depositing color filters on high-PPI microLED displays. To learn the latest about these te...