Sputtering remains the technology of choice for creating conformal package-level EMI shielding, which itself is a major trend in the electronics industry. For some years now, there have been attempts to replace the incumbent sputtering with spraying. The advantages are low Capex as well as non-vacuum operation, although these advantages may not be enough to overcome the momentum of incumbency. However, there are now two approaches based on digital printing of conductive inks to create conformal package-level EMI shielding. The digital nature of the coating enables mask-less area-selective metallization, which is an important advantage compared to sputtering when it comes to complex multi-chip heterogenous packaging or SiP package in which only a part of the package will need to be coated. One approach has been developed by Heraeus. It combines multi-head inkjet printing with their particle-free inks. Heraeus is offering a manufacturing-level turnkey solution, making it easy for customers to adopt its solution. Furthermore, the thin and smooth nature of the coating suggests it is effective even for mmWave frequencies and beyond, meaning that a single solution will suffice to cover sub-5G range, mmWave range, and many future frequency ranges. Another less mature approach is being developed by Ntrium in Korea. Here, they deploy aerosol printing. The results below were disclosed at TechBlick in May 2021. It shows aarea selective metallization on a 8x12mm2 IC. The aerosol head moves at 10mm/s. The Ag nanoparticle coatings are 1.1- 1.3um thick, which is thinner than spray and in the same range as inkjet. Aerosol offers a focused jet, enabling high resolution, but it may at the same time limit coverage area per pass. We do not know the latest developments but the plan in May 2021 was to achieve the following until late 2022/early 2023 UPH 1000 /system --> 4000/system Headspeed: 5mm/s --> 15mm/s Thickness: 1um/pass -->3um/pass Width: 500um/pass -->1mm/pass

Elepahntech (Japan) has spent more than $40m developing a technology based on IJP and plating to additively manufacture flexible PCBs (FPCBs) on PI as well as PET layers. The process is shown below. Here, the additive nature of the process means that the production process is environmentally friendlier and does not involve etching chemicals. Furthermore, the digital nature of the patterning (inkjet printing) means that designs can be changed faster. Here, inkjet printing is used to first print a thin silver nanoparticle track on the PET or PI substrate. The layer- which must adhere well to the substrate- is then thickened by copper (Cu) plating. This hybrid approach ensures that (a) bulk-level conductivity similar to PCBs is achieved and (b) soldering can be deployed without the challenges faced by conductive inks. These are two important points enabling the technology to be positioned as an alternative to etched FPCBs The linewidth is currently limited by the resolution of inkjet printing. The L/S (linewidth over spacing) is now around 200um/200um. With laser scribing, this can be further reduced to 100/100um today. In the future, the development target is an L/S of 20/20. Furthermore, the technology currently is applied only on flat surfaces. In the future, however, the seed layer could be applied to a 3D layer, enabling 3D metallization too.

Printing micro bumps with solder paste or conductive adhesives is an elegant solution. However, most printing techniques will struggle to achieve the current, let alone, future resolution requirements. Indeed, this requirement will become even more challenging as microLEDs shrink in size (roadmap is towards 5x5um2). Microgravure offset printing on wafers represents an elegant solution. Here, you can see an example of work by Komori, showing how 6um (diameter) solder pads were printed on a wafer with a pitch of 30um. This is an excellent resolution. After reflow, the solders spread, making the diameter of the solder bump15um. To learn more about this technology, and other technologies essential in manufacturing of next-gen microLEDs, check out the confirmed speaker list for TechBlick’s microLED event. You can see the full agenda here

As microLED’s inevitably shrink in size, the question of how to bond and contact them to the substrate becomes ever more important. This need will drive innovation both in terms of material development and deposition technology. An interesting additive approach is based on electrohydrodynamic printing (EHD), which can digitally print inks with few-micron resolution and over a spectrum of viscosities (can handle far more viscous than inkjet can). The image below by Enjet presented at a previous TechBlick conference, shows how conductive bond pads and adhesives in the scale of 15-20um were digitally (EDH) printed. Currently, the EHD is generally somewhat slow, but the recent development of multi-head printers may change this. This is an important technology area to watch. To learn more join TechBlick’s specialist microLED event. Check out the confirmed speaker list here. It is truly a world-class agenda . See full agenda here

This is an excellent chat by Eric Virey (Yole showing how LED dies are expect to shrink in size, going from mini-LED region (e.g., 125x255mm) to ultrasmall microLED region (5x5um?). This driver is essentially because it increases PPI and drives down cost as well as transfer time/cost since more LEDs are produced per wafer. To sustain this trend, many other technologies need to evolve from more efficient small-sized red LEDs to microbumps to better tiling and metallization techniques and transfer technologies. Join TechBlick’smicroLED event with a world-class agenda covering all key technologies in the field. See agena here

The standard metallization technology for Si solar cells is screen printing. Today, it can print 35um linewidths and is expected to evolve down in production to 20um linewidths. The productivity for a 182x182 mm2 wafer is today around 7000 wafers per hour, setting the industry benchmark for any alternative technology. In the past, inkjet printing tried to offer an alternative, but could only handle low viscosity nanoparticle (expensive) inks with low aspect ratio. It was proposed to use inkjet as the technology to print seed layer, but inkjet – as a tool for PV metallization- has not yet gained significant traction, despite more a decade of development. Fraunhofer ISE has developed a novel multi-head non-contact digital printing based on high-resolution dispensing. This technology – spun off into HighLine Technology GmbH – can digitally print high-aspect ratio (:1) ultra narrow linewidth (17-19um) metallization lines using high viscosity solar Ag pastes. This technique may improve upon the linewidth capability of screen printing whilst being inline and non-contact, which can lead to lower breakage/reject rate especially for ultrathin wafers. Join TechBlick to learn more about the complete world of printed electronics, additive electronics, and photovoltaics Source: https://doi.org/10.1002/solr.202000475

Speaker: Terho Lahtinen | Company: Movesense by Suunto Oy| Date: 10-11 March 2021 | Full Presentation Movesense is an open sensor platform for creating new solutions to track motion, heart rate and ECG. Movesense is used for building wearable sensor concepts and for integrating sensors with apparel. To enable smooth apparel integration and to provide context information for the sensor, Movesense team of the Finnish sports watch expert Suunto worked together with TactoTek, another Finnish tech company specialized in IME, to develop a flexible connector element that includes in-molded electronics and can be applied to clothing with typical textile industry methods. The presentation describes the project background and steps in practice. Join TechBlick on an annual pass to join all live online conference or online version of onsite conference access library of on-demand talks (600 talks + PDFs) portfolio of expert led masterclass year-round platform https://www.techblick.com/ And do NOT miss our flagship event in Berlin on 17-18 OCT 2023 focused on Reshaping the Future of Electronics. This event attracts 550-600 participants from all the world and offers a superb ambience and dynamic exhibition floor. To learn more visit https://www.techblick.com/electronicsreshaped To see feedback about previous event see https://www.techblick.com/events-agenda

By Piotr Trzaska | Noctiluca | https://noctiluca.eu/ OLED (organic light-emitting diodes) is the display technology based on a thin layer of organic emitters that emit light of a specific color. Key parts of the structure of OLED displays are OLED emitters - the chemical compounds in form of a powder responsible for luminescence - light emission after application of electric current. The quality of the image displayed using OLED technology, the saturation of the color, and the intensity of the light depends for the most part on the emitter parameters, which have evolved with the development of the industry. OLED technologies have been divided into 4 generations, depending on the characteristics of the emitter, which determine the properties of the diode constructed with its use: 1st generation - fluorescent diodes, 2nd generation phosphorescent diodes, 3rd generation based on the TADF effect, and 4th generation based on hyperfluorescence. Noctiluca develops third- and fourth-generation OLED TADF emitter systems, which will become an alternative to existing technology. Why? Let’s find the answer while analyzing all the generations. First generation emitters, so called “fluorescent OLEDs” OLED displays of the first generation are called fluorescent OLEDs and use organic emitters. As the intersystem crossing (ISC) between states of different multiplicity is impossible due to basic laws of physics, only transition S1 -> S0 is allowed and radiative. Upon an electrical excitation, only 25% of formed exciton are of singlet multiplicity and are emissive. The rest 75% are of triplet multiplicity and are not involved in the emission of light. This is why the internal quantum efficiency (IQE) of fluorescent OLEDs is capped to 25% and as a result external quantum efficiency (EQE) to a few percent. The most common today second generation emitters To utilize the rest 75% of excitons, metallorganic complexes were discovered and named as OLED emitters of the second generation. As the presence of rare metals like iridium and platinum causes very strong spin-orbit coupling, in phosphorescent emitters T1 -> S0 transition becomes radiative and ISC process between S1 and T1 also takes place. This approach theoretically allows the utilization of up to a 100%of formed excitons for the emission of light and up to 100% of IQE. The EQE values of the best phosphorescent OLEDs are about 30%. Even though phosphorescent emitters offer high efficiency and potential for application in OLED technology, the presence of expensive and toxic rare earth metals and precious metals in the structure of complexes causing problems with recycling, limit their application on an industrial scale. Moreover, to date, there has been a notable lack of blue emitter, that represents 70% of display light emission, of second generation. TADF - third and fourth generation emitters The problems with 1st and 2nd generation of emitters is what stimulated the intensive research on other efficient emitters but without metals in structure. One of the promising phenomena is thermally activated delayed fluorescence (TADF). TADF emitters thanks to the appropriate design have a very small energy difference between S1 and T1 states (ΔEST). When the exciton lifetime in the triplet state is long enough, the RISC process becomes allowed and is thermally activated. Triplet excitons are converted into singlet excitons – emissive, and emission of delayed fluorescence occurs. The theoretical maximal value of IQE is 100%. The development of OLED technology has not stopped at the third generation. The requirements for the next generation are high efficiency, high color purity, and considerable lifetime. One of the most promising approaches which meet these conditions is hyperfluorescence – the concept developed by scientists from Kyushu University. Hyperfluorescence is a term known since 2013 when Adachi and his group developed this approach. In a hyperfluorescence, the TADF molecule serves not as an emitter but efficiently transfers the excitation from the host to the fluorescent dopant. During the TADF mechanism, the electrically generated triplet excitons are converted to singlet excitons, then through FRET, the S1 state of fluorescent dopant is filled and light emission occurs. This approach is attractive because of an extremely narrow emission band, better stability, and high color purity. The theoretical limitation of IQE for hyperfluorescence is 100%. Why do we need the 3rd and 4th generation of emitters? TADF emitters are expected to drive the growth of the OLED industry in the coming years because they address many problems: • They are more energy efficient - 5G phones have up to 33% higher power consumption than 4G phones, foldable devices will allow for a bigger display, and slim design means less space for battery – having all this in mind OLED displays with 3rd and 4th emitters could save up to 30% of current energy consumption • They are better for the environment - OLED displays with 3rd and 4th generation of emitters do not require heavy metals and Rare Earth Elements • They are cheaper • They prolong device life and eliminate the burn-in effect of displays • Additional value: efficient blue emitter, unattainable for 2nd generation Within the OLED market, the use of second-generation emitters has grown rapidly over the past few years - but not in all colors. Although efficient green and red light emitters have been successfully produced, constructing high-quality blue light emitters seems to be an insurmountable problem - the market is still using blue emitters of the older, 1st generation. The main technological goal of OLED emitter manufacturers is to create and implement next generation emitters (3rd and 4th generation OLEDs), and to break the technological barrier associated with blue light emitters. To date, however, no one in the world has succeeded in creating an effective 3rd or 4th generation RGB emitter that would be commercially implemented (one use case with yellow monochromatic display has been rolled out). Obtaining 3rd and 4th generation emitters will be a true technological breakthrough.

Speaker: Erik Kremers | Company: SALD | Date: 9-10 Feb 2022 | Full Presentation In all growth markets, maximum throughput at the lowest possible costs is essential for success! SALD has developed a unique technology that makes this possible, which is protected by several patents. This technology has been incorporated into a compact machine that can be used for research as well as for small-scale production. It does not matter which material is involved: battery electrode, solar cell, OLED or foil. Moreover, SALD is the only company in the world that has the expertise to subsequently quickly and reliably upscale the Spatial ALD technology to high volume production. In Spatial ALD (SALD) precursors are continuously supplied in different locations and kept apart by an inert gas region or zone. Film growth is achieved by exposing the substrate to the locations containing the different precursors. The process is very fast and compatible with fast-throughput techniques such as roll-to-roll (R2R) and is versatile and cheap to scale up. In addition, one of the main assets of SALD is that it can be performed at ambient pressure and even in the open air, while not compromising the deposition rate. Join TechBlick on an annual pass to join all live online conference or online version of onsite conference access library of on-demand talks (600 talks + PDFs) portfolio of expert led masterclass year-round platform https://www.techblick.com/ Our next battery-related event will take place on 15-16 FEB 2023, covering 1) Solid-State Batteries: Innovations, Promising Start-Ups, & Future Roadmap 2) Battery Materials: Next-Generation & Beyond Lithium Ion The speakers include: General Motors, Graphenix Development, Brookhaven National Laboratory, Fraunhofer IKTS, RWTH Aachen University, Lawrence Livermore National Laboratories, Meta Materials Inc, Skeleton Technologies, Solid State Battery Inc, Argonne National Laboratories, OneD Battery Sciences, VTT, Leyden Jar Technologies B.V., b-Science, Rho Motion, Wevo-Chemie, LiNA Energy, CNM Technologies, Ionblox, Empa, Zinc8 Energy Solutions, Avicenne Energy, Echiontech, South8 Technologies, Basquevolt, NanoXplore, Chasm, Li Metal, Sila Nanotechnologies, Quantumscape (tentative), Fraunhofer ISI, etc https://www.techblick.com/

Ultrafine line screen printing: emerging application and competing technologies TechBlick prepared this presentation for the Advanced Screen Printing Workshop organized by Asada Mesh (June 2022, Chicago). You can watch and read the full presentation here. You can also view the slides. The theme are Existing and emerging applications for ever finer Screen Printing linewidths (sub-15 micron meters): Photovoltaic metallization | MicroLED wrap-around edge electrodes | Fan-out structure for flexible hybrid electronics | Transparent HMIs |Transparent Touch Displays | Edge Electrodes | MLCC | LTCC Hybrid and direct (non-digital) printing technologies towards sub-micron linewidths: Hybrid screen printing (print + etch/ablate) | R2R flexo printing | R2R Gravure Offset Printing |S2S Offset Printing | S2S Reverse Offset Printing |R2R Reverse Offset Printing | R2R Imprinting + Filling | R2R Photolithgraphy You can download the slides at the bottom of this blog. Simply scroll down mmWave 5G RFFE based on LTCC and printed Ag metallization LTCC with printed Ag metallization is an excellent choice for heterogeneous integration of electronics, especially for high-frequency (mmWave and 5G) and harsh environmental conditions. Indeed, it shows our printed electronics can play a role in the 5G/6G communications infrastructure. In this study, DuPont demonstrates an Antenna-in-Package (AiP) which integrates a beam steerable antenna array in a Radio Frequency Front-End module (RFFE) operating at 28 GHz and incorporating an Anokiwave IC with a 2 x 4 patch antenna array. The ceramic dielectric (so-called GreenTape) shows excellent dielectric properties through 100 GHz while maintaining Dk of 7.1 and Df of <0.0010. It also shows stable properties throughout the extreme temperature range (-50°C to 150°C). In this study, screen printed sintered Ag metallization was used for ground planes, via fills, signal lines and solderable pads. The data in this study shows the viability of LTCC for mmWave and 5G applications. It is an exciting solution with low moisture update, good temperature stability, etc. As the density of parts in LTCC based heterogeneous systems rises, screen printing will also need to go to finer lines to support this densification, but that is a story for another day Digital printing of screen printable pastes for rapid prototyping??! Screen printing requires tooling which limits prototyping and rapid product iteration. Digital printing uses nanoinks which have a more limited menu of material options and are more expensive, and in any case are not always the ultimate material selected in final volume production. This leaves a gap in the market for digital printing of off-the-shelf screen printable materials and pastes. Voltera is developing a prototyping benchtop machine aimed at solving this problem. This product will be launched at the TechBlick show in Eindhoven (12-13 OCT 2022). It allows users to rapidly digitally print using different screen pastes. The digital printing processes largely self caliberates, allowing uses to experiment with different materials and formulations without needing to go through the full learning curve/print optimizaiton process each time. The benchtype size also allows one to keep this in the lab, enabling rapid prototyping. The digital direct wire printing head allows printing on different substrate materials as well as over flat and 2.5D/3D shapes. Applications demonstrated here: (1) soft insole pressure sensor on TPU | (2) wearable heater integrated into clothing (denim) | (3) thermally formed mug heater. Digital Laser Processing of 3D Electronics Combining digital printing (inkjet, aerosol, etc) with site-specific digital rapid laser-based sintering has many advantages. In the talk below, you will see various examples from Fraunhofer ILT in Aachen, Germany. Multi-layer piezoelectric actuators: The structure is multi-layer [(PZT (140nm)-->LNO (30nm)--> PZT (140nm)-->LNO (30nm)--> PZT (140nm)-->LNO (30nm)]. Therefore, it is essential to have rapid sintering otherwise TACT time will be too long. Here, Fraunhofer ILT suggests that laser sintering (inkjet layer 1 --> laser sinter --> repeat) can be an excellent solution. Strain sensors on and within 3D-printed bionic component: here, the insulating layer is first dispensed. The strain sensor materials are then digitally (inkjet) printed onto the surface of the 3D part and then digitally laser-sintered. The ability to digital print and sinter means that only the required parts will be metallized and subjected to heat treatment. As such, it saves time, prints on non-flat shapes, and maintains integrity of the 3d printed mechanical parts. In another variation of the same device, they can stop the 3D printing process to digitally print (aerosol this time) and digital laser sinter the electronic components before resuming the 3D printing process. This way, the electronic functionality will become embedded in the structure itself. 3D Pad Printing on 3D Surfaces: 5G antenna for smart phones Metallising 3D structure has many applications. The common technology approaches to LDS (laser direct structuring) or digital aerosol printing. The fomer is a multistage process with a relatively large machinery footprint, but offers high adhesion and bulk-level conductivity with ease of soldering. The latter is a two-step digital process with small compact machine. However, it offers ink-level conductivity, which can be low especially on low-T substrate. Henkel has recently demonstrated pad printing - an old technique- for 3D electronics. This technology enables printing of inks onto 2.5 and 3D plastic structure, thus offering an alternative to LDS and aerosol. It is a simpler process than the other two. The process will not create fine structure but can print thicker (thus more conducting) lines using high viscosity pastes. It is also a robust and relatively low-tech process compared to LDS and aerosol. As shown therein, in this process, a conformal silicone pad first pickes up the ink from a metallic plate. The ink formulation must ensure good adhesion to the silicone pad. The pad then stampls the 3D surface. Since the pad is conformal, it follows the shape of the target substrate, achieving non-flat or 3D coating. Applicaiton examples demonstrated herein are developed with Henkel's Chinese partners: printed 5G antenna on the outside polycarbonate frame of a mobile phone, achieving 10mOhm/sqr/mill printed conductor on the inner side of the plastic to connect with mainboard

This presentation was developed for the Advanced Screen Printing Workshop organized by Asada Mesh. The theme was fineline printing. In this presentation, we discuss the following: Existing and future applications for ever finer Screen Printing Linewidths (sub-15micron meters). Photovoltaic metallization MicroLED wrap-around edge electrodes Fan-out structure for flexible hybrid electronics Transparent HMIs Transparent Touch Displays Edge Electodes MLLC LTCC Hybrid and direct (non-digital) printing technologies towards sub-micron linewidths Hybrid screen printing (print + etch/ablate) R2R flexoprinting R2R Gravure Offset PRinting S2S Offset Printing S2S Reverse Offset Printing R2R Reverse Offset Printing R2R Imprinting + Filling R2R Photolithgraph You can download the slides at the end. Please scroll down This is an automatic transcription of the full presentation. It has not been proof read so there may be errors. This is here to help in case you prefer to read Hello, everyone. My name is Kasha. I am the CEO of TechBlick. We are really the home of the global community for additive electronics, for printed flexible hybrid electronics, 3D electronics. And we provide our community members a year round programme of curated onsite and online conferences and masterclasses market studies and beyond. The presentation itself has two parts. So the first part. The presentation will be looking at applications which will benefit or which will require ever finer screen printed line width. And then the second part of the presentation will be looking at non digital printing techniques, hybrid and directly or fully additively printed techniques which allow one to take the linewidth from, let's say, 30 or 40 micrometers down to a few micrometers and then eventually to sub micrometer range. Photovoltaics So first, as I mentioned, we are going to look at applications which require or which will benefit from ever finer screen printed line widths and the first. Important application is, of course, silicon photovoltaics is, you know, one of the biggest applications for conductive inks and for screen printing in electronics is metallization of silicon PV wafers. And if you look at this chart here, if you look at the orange lines, what you find is that is the line width of the printed metal mesh as the printed metallization. You can see the current state of production today is something around 34 to 36 micrometers today and it is coming down very, very fast. So it is expected that within a few years we'll be reaching 20 micrometer line widths and maybe even lower. What is also interesting about this application is that screen printing is actually a very, very productive process. So here you can see the wafer per hour rate for the back end processes, which also include the metallization step screen printing. The wafer size is something around 180 to 182 millimeters. And you can see that today we are something around 7000 wafers per hour. And this is projected to rise to something around, let's say, 10,000 wafers per hour by the end of the year. So you already have screen printing in this very productive high volume production setting, producing, you know, 30 to 35 micrometer linewidths and evolving the process down to 20 micrometer line width. And here on the left, you can see an example of what I think is a very good representation of the state of the art. And here you can see a screen printed sort of finger on a perc solar cell. This was made by Fraunhofer ISE. And you can see very nice, with 19 micrometers and a very nice aspect ratio of about 18-19micrometers. And so yeah, I mean that, that already tells you that there is an application in high volume production which has narrow language in the line which will go down to 20 micrometers and beyond. But I want to say that solar metallization is really relatively an easy application, and that is because the pitches are very wide and at the same time broken lines, interrupted lines, can to some extent be tolerated. So there is some tolerance of defects. MicroLEDs Another application which I think would benefit as an example for ever finer screen printing metallization lines is the Micro-led display application, so microLEDs are a very hot display topic. And one of the key uniques of this display technology is that you can create bezel free displays. So when you have bezel free displays, it means that you can form a larger display by putting together many kind of smaller tiles and building up the big display. So here you can see an example of one such display tile. So we have glass and on this you deposit the TFT, the thin film electronics on the glass. You might deposit the the bonds, the micro bonds or something, and then you transfer the micro LEDs on the top. the driverwould be on the bottom. So first you can imagine that the two surfaces on the top have to be metallized (see the lines on the top surface). You have to realize the lines on the bottom surface, connecting them to the pins on the driver. And then you have to somehow connect the front to the back. And one way, of course, would be to drill via into the glass, fill the through glass vias. But this is really not elegant. And as far as I know, nobody uses this process. So a more interesting approach would be to create this so-called wraparound edge electrodes. So you would have these electrodes going around the edge connecting the front to the back. So this example, I believe, is from Applied Materials, and this one is from Corning. Here is an example again by Applied Materials showing you the kind of process so that the front metallization would be printed on a chamfered glass. Then the bottom metallization would be screen printed on the chamfered glass, and then the glass would be rotated to print the edge electrode and then cure. So first you need very good alignment. You need very, very highly conductive inks and you need to control your printing process so that you don't end up with peaks around at the chamfered edge of the glass. Here's an example where the chamfered edge, the example on the on the bottom left, you need to have a topography of a printed line which is relatively smooth, with no major peaks around the edges. And then the thickness would be for a given connectivity level of inks something around 3 to 6 micrometers after drying. So here you can see an example of fine line printed, a screen printing also around the edges and the line width of the spacing is 40 to 60 micrometers in this case. So already this is by some standards very, very fine line screen printing. But perhaps this is the technology of yesterday? And the reason I mentioned this is because micro led dies are shrinking in size. So the early generations were actually mini LEDs with the dies being something around 125 by 225 micrometer size. And now we are going down, and this chart is put together by, Yole and you can see that we'll be going into a territory where the dies are something around maybe ten micrometers by ten micrometers. And as we approach that range, the bond sizes are going to get smaller and also the metallization lines are going to get ever, ever narrower, which means that the screen printing, if screen printing is to stay competitive in this technology, it also has to produce ever finer lines. And so here's an example again by Applied Materials. I think you can't see it in the recording because my video is here, but this is a 15 micrometer printed screen printed line. So it shows you that you can print that level. And I'm sure all of you in this expert audience know this, that one can print 15 micrometers, but this application is not like a PV application. It is very challenging. It cannot tolerate broken interrupted lines because that would imply a dead microleds and therefore a dead pixel. And in the worst case, you might be able to tolerate some defects on 10% of the tiles, but on 90% of the tiles, all the metallization, have to be defect free. So not only one needs to deposit very, very fine lines with good control of topography, high conductivity, good wraparound coverage. But also one needs to do so without too many broken lines. So this is a challenge for the industry and I think this workshop would help the industry achieve these targets. I should say here that the competition actually here is actually one of the competitions here is PVD and Samsung uses a PVD process developed by a Korean company in which in the PVD chamber they stack all the glasses together and then they rotate them and they get PVD to deposit also around the edges. So PVD is always, always the competition in these cases. But if screen printing could produce fine lines, 15 micrometers or less without defects, maybe this could be with very little defects. Screen printing would remain competitive in this application. Flexible Hybrid Electronics (fan-out) So another application that I wanted to highlight, and I think it's an interesting one, is around flexible hybrid electronics. So flexible hybrid electronics is about combining the performance of rigid ICs, rigid silicon ICs with the low cost production and the flexibility of printed flexible electronics on low temperature substrates like PET. And I think many of the technology hurdles which have held back this technology are being cleared away now. So people are developing ways to use standard solders or developing materials with solder like properties, i.e. self alignment on heat or on other low temperature substrates. People are finding ways to thin ICs and make them flexible. People are finding ways to do pick and placing of these very thin ICs, sometimes even in a roll to roll set up. So many of the technology hurdles are being cleared. And the reason I have it here in this screen printing workshop is because I think screen printing could also play a role here, at least fine line screen printing could play a role. So look at this example here. This is, I think a demonstrator by Nexflex, you have the IC here, you have the wiring lines printed. Let's say the wiring lines can typically be screen printed. The pitches are wide. The linewidth is well within what screen printing can do. Then one needs to go from the wiring to the ICs. So in the pictures, the pins of the ICs are much narrower than the wiring. So one needs to have this so-called fan-out structure connecting the pins with the bumps and connecting the pins to the actual wiring. And here's an example of a fan-out structure. So right now, screen printing cannot do the wiring and the final structure just based on the screen printing process. So different processes have to be combined. But what I think if fine line screen printing would be further advanced, then this would be possible to screen print the fan-out as well as the wiring and the requirements for the line width of the fan out is something around 30 microns or less with a pitch of around 60 microns or less. So this particular image is from Netflix and some of these images I took from a presentation by Komori in Japan and adapted them just for reference. Transparent HMIs So I wanted to also say a few words about this very interesting application for Transparent Touch or HMIs. I mean, here the competition is maybe trying to replace PEDOT transparent dot layer, which is also printed in very high volumes. But in this case, in the case of these metal mesh structures, one maybe does not need a protective layer. Simplifying the structure and making it also thinner. This example is by sSun Chemical as other mesh type, CFR and others. So this is a well known example in this audience that actually I think Erika will have presented on this. . So I won't I won't discuss this particular application. But just to say the linewidths, I think, are around 30 or 35 micrometers, so you can see the meshes, but it is probably okay for these switch or HMI applications, but. Say that, you know, the requirements for a transparent touch display are very different from the requirements for a transparent switch. Transparent Touch Displays So when we talk about a transparent display like on your phone or on your tablet, then the line width needs to be a lot narrower. So here you can see an example of the kind of the different ranges to micrometer range for me, so sorry. So maybe let me explain this again. So here you can see the ranges. If your linewdith is wider than 4 to 5 micrometers, it is possible to see the structure even though it is transparent. If the line width is around 2 to 4 or five micrometers, then it is very difficult to see. But if one looks very, very carefully, one can sense. I can recognize that something is there and if it's below two micrometers, probably it's totally invisible. And I just want to show you in this table what companies are doing, what kind of line widths they are printing for the metal meshes, which act as a transparent conductive field for display industry. So these are different companies. These are different processes. I won't go into the processes in this presentation, but just look at this column here showing the line width. So one can clearly see that the line widths are generally sub four micrometers and that shows you the requirement for this industry. So I just have this slide here to kind of make a contrast between transparent touch displays and transparent touch switches. Edge Electrodes Now another interesting application. I think if if screen printing could print ever finer lines, then screen printing would stay would have stayed relevant in this application and would be very competitive process that is for printing the edge electrodes in a transparent touch display. So here you can see an example of a kind of an edge electrode series. The requirements because the bezels have been getting narrower and narrower, the line width to spacing requirements have also shrunk over time. So I have here two examples of companies offering a full, transparent film structure, including the transparent layer and the edge electrodes. And here you can see the line with over the spacing in micrometers of just the edge electrode just to give you a sense of what kind of requirements people have. So if screen printing is to stay relevant, it needs to target sub 15 or so, maybe at least sub 20 micrometer micrometer range And here is a kind of an evolution chart. Very rough, very, very, very approximate chart showing line with over the spacing requirements. Standard screen printing maybe takes you down to 40, 50, 40 micrometers then fine down screen printing. So screen printing technologies which are being developed now and together with the ones that are the subject of this workshop, maybe take you down to 20-15 micrometers, then people start to use hybrid processes. So I'll give you an example later on screen printing plus laser plus photolithography. And then there are other non-screen printing techniques which are put here in green. So all the blue ones are either direct or hybrid screen printing and the other ones are non screen printing processes. So basically I guess the message here is that if screen printing could do very fine lines, then it would be able to participate in this market. Also printing the electrodes for transparent touch display. Other Applications (MLLC, LTCC, etc) So. We want to focus on alternative technologies. So so far in the application area, we talked about photovoltaic metallization and how the line width will go to 20 micrometers or below with very, very high wafer per hour throughputs. We looked at the microgrid application and how the requirements there are moving towards 15 micrometer line width and below, but with very exacting sort of defect and yield requirements. We looked at flexible hybrid electronics and how it might benefit from printing the wiring or screen printing the wiring and also screen printing the fan out. We then said a few words about transparent light switches, transparent type screens, edge electrodes. And before going to the alternative technologies, I just want to mention maybe a couple of applications which I omitted in my presentation but are very important. One of them is MLC, where nickel powders are screen printed. Maybe some do gravure printing, maybe 30% or so do gravure printing for the mobile application, but the majority are still screen printed and will remain so. And the reason I mentioned this is because the thickness of the lines is going down and down. And I think now it's between 1 to 2 micrometers, the thickness of the final line and the other application is LTCC. LTCC is, I think, a very competitive technology for 5G. And when you think about 5G and LTSC as a substrate technology and if you think about heterogeneous integration of different ices in an LTC kind of a system, then one needs to have very, very fine line printing techniques with very good edge definition to support 5G lines and also very, very narrow, narrow printed lines. I think they are also the requirements would be very soon about 15, 15 micrometers. Technologies Towards sub-Micron Printing So in the next few slides, what I want to do is I want to tell you about technologies which allow you to go to find very fine lines, sub micrometer or micrometer range. So we'll look at screen printing plus photolithography. We look at role of flexible printing, we look at gravure offset printing, sheet to sheet offset, reverse offset and so on. And basically you will see how we go towards ten micrometers and then we go to sub ten and sub five and sub three and then in some cases sub one micrometer. Hybrid Screen Printing So just two quick, quick, quick slide on this one. So this is a hybrid screen printing process. The idea is that the ink itself in this case contains a photosensitive material. So you don't need a photoresist. So as you can see here, you can screen, print it and then expose it to UV light directly with the photoresist and then etch. And then this will allow you to get very, very fine lines. So in this case, this material is Toray. the references are behind my behind my image. So this is my Japanese company. And these examples, this example here is linewidth over a spacing of about about ten, ten by ten micrometers. This is for curing for 140 degrees Celsius. So compatible with PET substrates. But I think what is important here is that the conductivity of the line is not very high because you also are loading other additives into the formulation. If you want a higher temperature version that is compatible with PI or glass, then you can adjust the process and go to even finer lines. 2.45 micrometers or eight eight micrometers. So that was a hybrid screen printing process, a screen print plus etch. R2R Flexo Printing In this case, I want to talk about a direct, flexible printing process. Of course, flexible prints, thin lines, just just how it is. And this case is developed by Kodak, who has a very good laser process for creating the plates with flat top dots. And they created a metal mesh here. This is a semi additive process where they flexo print a catalyst layer and then they use plating to thicken the layer and achieve bulk like conductivity. And if you look at these metal meshes here, the only reason I have it here is that the linewidth can be around eight eight micrometers. So it shows you that with this technique one can go down to sub10 micrometers. R2R Gravure Offset Here is an example of road roll gravure offset printing being developed for a number of years in Japan. And I don't want to go into the details of the actual technology, but you can see a kind of the narrow web tools which are being developed now. The web speed is relatively, relatively low, but here I think they print with submicron particles. So let's say a nanoparticle ink is used to print these metal mesh lines and you can see that the lines are five micrometers. S2S Offset Printing Another example which I liked again by a Japanese company. This time you can see the name here. And the reason I like this here is that this is a sheet to sheet offset printing process. And you can see they can print these very, very complex patterns with just 1.5 micrometer linewidth. And here, too, they're using silver nanoparticles. You can see it's a very thin line, maybe 250 nanometer just thickness cured at low temperature. So you can cure the ink at 120 to 400 degrees Celsius. But the reason I basically have it here is that this shows you that with direct printing sheet sheet on various substrates, as long as it is sheet to sheet, one can achieve 1.5 or three three micrometers. S2S Reverse Offset Process Then if you want to go below that level and achieve kind of one micrometers, then I think an interesting sort of process is the reverse is the reverse offset process. Here you can see an example by. This was, I think, published recently and showcased at our conference just in March at the TechBlick show. And you can see a kind of a desktop reverse offset printing machine. Reverse offset printing technique is very unique because you usually have a PDMS roller mold, you totally ink it, so it's totally covered with ink. Then the ink semi absorbs into the PDMS, which means that you're not dealing with a complete liquid, but because it is in a semi dried state, then you can control the wetting a little bit better and then it is brought into contact with the relief plate. Some of the patterns are removed, removed, and then the roller mold is brought into contact with the final substrate and then the ink is transferred. So you can see that in this case, they have developed a process. They have developed a process which allows them to create metal meshes with just, just one micrometer line. So I think it is a very interesting process. I mean, reverse offset is good for these kind of line widths. I would imagine that the printed lines are generally very thin. So let's say from 20 to maybe 1000 nanometers, the printed resolutions could be about 0.5 or a little less to a few micrometers. And the printing speeds could be would be, well, less than 50 millimeters per second or so, just to give you some parameters about the capabilities of this process generally so. R2R Reverse Offset Printing? Here's another, I think, interesting technology. This one is, again, by a Japanese company. Unfortunately, the source is again falling behind my picture. So this is by Asahi Kasei in Japan. So you can see they're printing very fine lines. And I didn't have a video here, but these are continuous lines with very well defined edges and just 300 micrometers wide. One of the innovations here is that they have these roller molds, which they call a seamless roller mold, and it is patterned not using just laser, but with electron beam lithography. And you can see the kind of the features they can define on this roller mold, around one micrometer wide and five micrometer pitches. And this is a very, very smooth, smooth surface. And here you can see a couple of examples of actual kind of roller roller molds. This is, I think, 250 millimeters in width and about a hundred millimetres in diameter. So what is the actual printing process here? Undisclosed. But my guess is that this is also a form of reverse offset printing process. So the previous example that I showed you was the relief plate was flat. In this case, the relief plate is actually a roll, so it's a fully roll to roll process. And here you can see an application in this demonstrator. They are printing aligned with a three micrometers. So not at the leading edge of the of the capability, but it is a transparent kind of an antenna application for transparent RF ID for for putting it on products without without taking up real estate. So the RFID would be there without occupying any real estate on the packaging. R2R Nanoimprinting So I guess we are now almost approaching the end. There are only two slides left, I believe. So. I just wanted to say that there is a whole array of technologies which are hybrid and roll to roll, and they go to very, very, very fine lines. So this example is by Panasonic. Panasonic is not the only company developing this technology and is in fact, not the first. But I think it is kind of a state of the art. From what I can gather, because the way the process works is that you have a substrate, you coat it with a resin, and then you roll to roll emboss a pattern into the resin. Actually, they do it on both sides, so it's a double sided embossing process. Then they simply fill in the grooves with silver nanoparticles. So here you can see they can achieve a two micrometer line with with a good aspect ratio. And very, very good sort of sheet resistance of two ohms per square. What is really interesting about this process, I think, is that the conductive line ends up being embedded into the substrate. And what that means is that to increase the conductivity of the line, you don't actually have to print a thicker and therefore a wider line. So this is a classical example, but you could just make the grooves a little deeper. R2R Photolithography And I want to say just a few words about the competition, which is photolithography. And here's an example of a roll to roll photolithography. This is developed, I believe, by Dai Nippon Printing. The target market is transparent displays, and you can see the kind of the line with that they've achieved. So the first generation of their products had four micrometers line with the second had two micrometers, and now they've announced on kind of smaller sizes, one micrometer line width. So here's an example and I think they can do this to serve the market of sub 40 inch displays. Just, just gives you some information about the state of the art using alternative techs. So with that, we come to the end of the end of the presentation. Again, thank you for your attention.

This is an auto-generated transcript. It has not been proof read by a person threfore they may be errors This is your Thibaut. It's a pleasure for me to talk about the new range of product that we have developed by printing silver ink. So Henkel is well known for the sale of conductive inks, especially for screen printing. But we have a nice project in China where one of our customers ask for printable inks for antennas, and basically we develop those inks, especially to meet the customer demand, but also because it really answers to product requirements, especially it combines two trends. The main trend that we see is the trend of connectivity. We have all heard for many years about Internet of Things, you know, is the 5G. We are even talking about the Internet of everything in that the objects we have to communicate together. We have also to communicate to people, but also to cloud in order to process the data, in order to enable seamless communications between everyone and everything you need high quality antennas and they. Other trend that we will see also is the one of 3D electronics, because we want to have smaller and smaller objects with even higher integral functionality also always customized. So basically you want to turn some maybe thermoplastic enclosure into smarter ones. And the best way to to make it is maybe to incoperate components on plastic surfaces or to bring or so connectivity. So we have developed by printing for those who are not familiar with pad printing. Here is a small animation tool to explain. Basically, you will have a silicone band that is going to take up an ink from a metallic plate. So you need to have the ink that has good adhesion and free transfer to the silicone pad. And then the pad is going to stamp the ink onto the 3D curves of face. And because it's fully conformable, you have a nice surface coating. If you want to increase, for example, the thickness, you can make multiple stamping. It's a nice alternative to two worlds. And especially this is it has been used for smartphone applications. So for these smartphone applications, we have developed two things. The first one is printed on the outer side of the smartphone frame in polycarbonate is called Loctite Acid. 1203 That is very good conductivity t below ten milliohms per square at 25 micron thickness and brings the antenna functionality. We also have developed another contact link that is printed on the inner side of the of the plastic frame with very good abrasion resistance. It is Loctite 1204 in order to have the contact with the main board, a main board of the smartphone, and in order, of course, to contact the outside of the antenna and the inner side contact pad we also have developed a ink not not for printing, but for dispensing to fill small holes in the plastic frame. So basically the combination of our inks and the printing technology brings many benefits to the customer applications. The inks offers a high performance, so very good conductivity, but also the low temperature curing that you need to avoid. The challenge of the smartphone frame can be cured to also have a very good reliability. And same because we are going to use inks and an additive technology, a printing one. You're going to, of course, to reduce the waste, for example, of copper plating that you will have from the LEDs process. But similarly, the inks are very good reliability, performance towards abrasion, humidity, damp heat and everything. But printing is also a well-known technique used for decades. For graphic printing, it can be easily scaled up. You just have to multiply the number of machines and also highly versatile because we have to change the cliché plate, the metallic plate, as you've seen two slides before to change the design. So also highly easy to customize. So this project has only been possible because we have the work of Chinese team at work in close collaboration with the customer, but also with part printing machine manufacturers to learn also on our side about printing. It's a nice solution as an alternative to like the direct structuring, LDS or also other types of antenna. But we are not we do not only have but printing inks for the 3D electronics or printing, and we also have a product portfolio. So if you want to learn more about it, you can either contact me directly, you have my email address, or we also have our virtual booth in room four and we will be happy to meet you there.