Tailoring the Crystallographic Texture and Electrical Properties of Inkjet-printed Interconnects for Use in Microelectronics

International audienceIn this paper, silver nanoparticles with a mean diameter of 40 nm are studied for future applications in microelectronic devices. The enhanced diffusivity of nanoparticles is exploited to fabricate electrical interconnects at low temperature. Sintering condition has been tuned to tailor the grain size so that electrical resistivity can be lowered down to 3.4 µOhm∙cm. In this study, a {111}-textured gold thin film has been used to increase diffusion routes. The combined effects of the substrate crystalline orientation and the sintering condition have been demonstrated to have a significant impact on microstructures. In particular, a {111} fiber texture is developed above 300°C in printed silver only if the underlying film exhibits a preferential orientation. This condition appeared as essential for the efficiency of the gold wire-bonding process step. Thus, inkjet-printed interconnects show a prospective potential compared to conventional subtractive technique and offers new opportunities for low cost metallization in electronics packaging

Impact of variable frequency microwave and rapid thermal sintering on microstructure of inkjet-printed silver nanoparticles

International audienceThe effect of thermal profile on microstructure is studied in the frame of thin films deposited by inkjet-printing technology. The role of sintering temperature and thermal ramp is particularly investigated. Fast heating ramps exhibit coarse grains and pores, especially when a hybrid microwave curing is performed. This enhanced growth is attributed to the quick activation of densifying sintering regimes without undergoing thermal energy loss at low temperature. Microstructural evolution of various sintered inkjet-printed films is correlated with electrical resistivity and with the Young's modulus determined by nanoindentation. A strong link between those three parameters is highlighted during experiments giving credit to either a surface or a fully volumetric sintering, according to the process. Sintering is then mainly triggered by surface mass transfer or by grain boundary diffusion respectively. Silver thin-films with an electrical resistivity 4 to 5 times higher than the bulk has been reached in a few minutes and with a Young's modulus of 38 GPa

Chip integration using inkjet-printed silver conductive tracks reinforced by electroless plating for flexible board packages

International audienceInkjet-printing of interconnects is a maskless technology that has attracted great interest for printed electronics and packaging applications. Gemalto is expecting by motivated and developing skills and knowledge in this area to be at the forefront of European Security innovation and to answer to a continuous market pressure for higher security, lower cost and more secure complex systems. With an increasing need for flexible and mass deliveries of advanced secure personal devices such as: electronic passports, ID cards, driver licenses, other smartcards, e-documents and tokens. EMSE is seeing in these new developments an exciting brand new area of research situated between material science and electronics. In this frame, deposit and pattern creation for chip interconnection require specific behaviors which have to be scientifically understood to pursue industrial harmonious implementation. Both groups collaborated on inkjet-printed electronic routing from deposition to sintering and characterization, using collaborative means provided on Micro-PackS platform

World Heart Federation consensus on transthyretin amyloidosis cardiomyopathy (ATTR-CM)

COPYRIGHT: © 2023 The Author(s). This is an open-access article distributed under the terms of the Creative Commons Attribution 4.0 International License (CC-BY 4.0), which permits unrestricted use, distribution, and reproduction in any medium, provided the original author and source are credited. See http://creativecommons.org/ licenses/by/4.0/.Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive and fatal condition that requires early diagnosis, management, and specific treatment. The availability of new disease-modifying therapies has made successful treatment a reality. Transthyretin amyloid cardiomyopathy can be either age-related (wild-type form) or caused by mutations in the TTR gene (genetic, hereditary forms). It is a systemic disease, and while the genetic forms may exhibit a variety of symptoms, a predominant cardiac phenotype is often present. This document aims to provide an overview of ATTR-CM amyloidosis focusing on cardiac involvement, which is the most critical factor for prognosis. It will discuss the available tools for early diagnosis and patient management, given that specific treatments are more effective in the early stages of the disease, and will highlight the importance of a multidisciplinary approach and of specialized amyloidosis centres. To accomplish these goals, the World Heart Federation assembled a panel of 18 expert clinicians specialized in TTR amyloidosis from 13 countries, along with a representative from the Amyloidosis Alliance, a patient advocacy group. This document is based on a review of published literature, expert opinions, registries data, patients' perspectives, treatment options, and ongoing developments, as well as the progress made possible via the existence of centres of excellence. From the patients' perspective, increasing disease awareness is crucial to achieving an early and accurate diagnosis. Patients also seek to receive care at specialized amyloidosis centres and be fully informed about their treatment and prognosis.info:eu-repo/semantics/publishedVersio

World Heart Federation Consensus on Transthyretin Amyloidosis Cardiomyopathy (ATTR-CM)

Transthyretin amyloid cardiomyopathy (ATTR-CM) is a progressive and fatal condition that requires early diagnosis, management, and specific treatment. The availability of new disease-modifying therapies has made successful treatment a reality. Transthyretin amyloid cardiomyopathy can be either age-related (wild-type form) or caused by mutations in the TTR gene (genetic, hereditary forms). It is a systemic disease, and while the genetic forms may exhibit a variety of symptoms, a predominant cardiac phenotype is often present. This document aims to provide an overview of ATTR-CM amyloidosis focusing on cardiac involvement, which is the most critical factor for prognosis. It will discuss the available tools for early diagnosis and patient management, given that specific treatments are more effective in the early stages of the disease, and will highlight the importance of a multidisciplinary approach and of specialized amyloidosis centres. To accomplish these goals, the World Heart Federation assembled a panel of 18 expert clinicians specialized in TTR amyloidosis from 13 countries, along with a representative from the Amyloidosis Alliance, a patient advocacy group. This document is based on a review of published literature, expert opinions, registries data, patients’ perspectives, treatment options, and ongoing developments, as well as the progress made possible via the existence of centres of excellence. From the patients’ perspective, increasing disease awareness is crucial to achieving an early and accurate diagnosis. Patients also seek to receive care at specialized amyloidosis centres and be fully informed about their treatment and prognosis

Printed Ag nanoparticles on Evaporated Au System: Impact of Microstructure on Mechanical and Electrical Properties

Nanoparticles have attracted tremendous interest for their thermodynamic size effect which is particularly valuable to reduce their sintering temperature. This asset is exploited for the fabrication of flexible electronic devices using printing technologies, especially interconnection features. Those printed interconnections require both a low electrical resistivity and high mechanical properties which are largely correlated with microstructure. In this paper, the combined effects of the substrate crystalline orientation and the sintering condition have been demonstrated to have a significant impact on microstructures. Silver nanoparticles with a mean diameter of 30 nm were inkjet-printed on {100} silicon substrates coated with either amorphous Si3N4 or with strongly textured {111} Ti/Au. The crystallographic texture and grain size of those printed films have been investigated after being sintered up to 500°C at 50°C/s using Electron Back-Scattered Diffraction. The results shows that a {111} fiber texture is developed above 300°C only on oriented films through out-of-plane diffusion. Electrical resistivity shows no dependency on texture since it is mainly affected by grain size. An optimal value of 3.4 μΩ.cm is achieved at 300°C using a fast sintering ramp of 10°C/s. Regarding the Young's modulus of nanofilms, nanoindentation measurements exhibited an oscillation between 38 GPa for smaller crystallites to 81 GPa for the biggest, which is compatible with wire bonding process

Optimal sintering technologies applied to inkjet-printed silver nanoparticles for microelectronics applications

As an alternative technology to replace lithographic process, direct printing of conductive nanofluids can thus be used to fabricate high resolution patterns, such as antennas and conductive redistribution lines. In the past few years, the use of metallic nanoparticles has undergone major development in microelectronics thanks to sintering achievements. To preserve electronic components functionalities, thermal budget need to be carefully considered, and thus a limited sintering temperature below 300°C should be used when printing nanoparticles. Nonetheless, the absence of any compacting step requires an exploration of novel sintering approaches to achieve a sufficient coalescence. In this frame, several sintering processes (thermal oven, rapid thermal annealing, selective microwave and laser curing) have been investigated to optimize the annealing of those thin films. The aim of this work is to analyze the induced microstructure of the above-mentioned sintering processes, and to determine how electrical and mechanical characteristics are consequently impacted. According the sintering technique and process parameters, an average grain size up to one micron can been achieved from initial mean particle size of 40nm, without exceeding a temperature range of 300°C. The microstructure characterization has been performed using electron backscatter diffraction (EBSD) in a field emission gun scanning electron microscope. Microstructural evolution of various sintered inkjet-printed films has thus been correlated with electrical resistivity and with the Young's modulus determined by nanoindentation. A strong link between those three parameters was highlighted during experiments giving credit to either a surface or a fully volumetric sintering, according the process. Sintering is then mainly triggered respectively by surface mass transfer or by grain boundary diffusion. Particular interests are shown for selective sintering especially when using microwaves and laser. Silver thin-films with an electrical resistivity three times higher than the bulk can be reached in a few minutes for a Young's modulus of about 50 GPa. In the meantime, the convective rapid thermal processing exhibits a various electrical resistivity and grain size. A Young's modulus even close to the bulk can be obtained when using a fast temperature ramp at 150 °C/sec for 15 minutes. This microstructural tailoring of printed silver nanoparticles were successfully implemented in the post-process step to achieve 600 nm thick films with very low resistivity and improved mechanical stiffness

Wire-bonding on inkjet-printed silver pads reinforced by electroless plating for chip on flexible board packages

International audienceThe nanoporous nature of the inkjet printed silver nanoparticles entail low hardness and surface effective contact area for being compatible with pads that are suitable for wire-bonding in electronic packaging. Electroless nickel plating is a selective metal deposition technique which can brings the required thickness and hardness for further pads processing. Here, a 1.7 μm thick nickel layer is deposited on top of 600 nm thick printed and sintered silver nanoparticles using Kapton polyimide as substrate. Prior to plating, a special attention was put on tuning microstructures of printed silver pads by sintering nanoparticles at various temperature ramps (0.1, 10 and 50°C/s) up to 200°C. Results show that fast sintering exhibits the lowest electrical resistivity which is suitable in printed interconnects. However, wire-bonding on nickel pads is best achieved when low sintering ramp is used. This slow sintering presents the highest adhesion strength at the nickel/silver interface since the pores dimensions were restricted to the nanoscale. The validation of the optimized bonding process came from the low electrical contact resistance between plated nickel and the bonded gold wire, and from the wire-pull test which is in accordance with the MIL-STD 883 standard. The actual results show that a compromise has to be found when emphasis is on patterning low resistive interconnects or stiff pads for wire-bonding applications. This compromise is tailored by the sintering engineering