Atotech (Germany)

As IC substrate technology advances towards fine lines and higher circuit densities, there is an increasing demand for copper (Cu) surface preparation to ensure reliable adhesion with lamination materials and resistance to external stress conditions. At the same time, it is essential to ensure process efficiency and support signal integrity. Conventional approaches often rely on multi-step roughening techniques to maintain adhesion in the presence of thermal, humid and chemical stresses between Cu and the dielectric. However, these techniques compromise the integrity of the Cu surface and are incompatible with the requirement for ultra-smooth conductors.This study presents an innovative, self-synthesized, organo-silane-based adhesion promoter designed to form strong chemical bonds between dissimilar materials such as various dielectric laminates and Cu surfaces (including electrolytically plated Cu). Unlike traditional roughening-based systems, our non-etch solution enables a streamlined two-step process that simplifies manufacturing, reduces costs, and maintains the high bond strength required for next-generation packaging, eliminating the need for aggressive copper etching, our non-etch solution allows for the creation of narrower lines and spaces, which are essential for advanced IC substrate designs.The system also demonstrates excellent chemical resistance to desmear process, which is necessary to clean blind microvias (BMVs) after laser drilling and prepare them for subsequent Cu filling. Smooth Cu surfaces typically struggle in these harsh conditions, but post-desmear testing of structured designs confirmed the integrity of the sidewalls and minimal wedge formation at the BMV interfaces. Roughness measurements show that our process does not alter the original surface topography. Extended IR Reflow and high-temperature accelerated stress testing (HAST) provide further validation of the durability of the interface. The effectiveness of the promoter in maintaining strong Cu-dielectric bonding under harsh stress conditions is demonstrated by FESEM and FIB analysis.As a global leader in laser, desmear chemistry and surface treatment, our understanding of interfacial processes extends beyond adhesion alone. This allows us to support customers with fully integrated bonding solutions, combining advanced materials, process integration and application expertise to meet the evolving demands of IC substrate manufacturing.

Tunnel oxide passivated contact (TOPCon) solar cells will likely become the most produced crystalline silicon photovoltaic architecture within the next five years. The technology relies on multiple thin films to improve cell efficiency by further reducing electron-hole recombination at metal-semiconductor interfaces. Lasers are used to remove the anti-reflection thin film layer to prepare regions of the cells for electrical contact formation (“metallization”). This process—laser contact opening or LCO—is challenging in that the underlying thin films must suffer minimal damage. TOPCon is an ideal architecture for implementing electrochemical plating metallization, which has certain advantages over conventional methods. In this work we report on the use of ultraviolet (UV) wavelength ultrashort pulse lasers for TOPCon LCO processing in concert with electrochemical plating metallization. Laser parameters selection is reviewed, and processing results are analyzed with optical and scanning electron microscopy. Complete solar cells are fabricated and performance metrics are discussed.

The rapid expansion of the artificial intelligence (AI) market has created an urgent demand for innovative and efficient solutions in the manufacturing of integrated circuit (IC) substrates. A critical aspect of IC-substrate production is electrolytic copper plating, essential for ensuring electrical conductivity, reliability, and overall performance of the circuits. Traditional copper plating techniques often face challenges in achieving uniform deposition and adequate copper thickness in through-holes, which are crucial for high-performance AI applications. This paper explores recent advancements in electrolytic copper plating technologies, focusing on the application of pulse plating in vertical conveyorized equipment to address these challenges and deliver superior results.

ABSTRACT In the field of printed circuit board (PCB) manufacturing, surface finishes play a crucial role, serving both as a protective layer and as a facilitator for various interconnecting techniques. Among the commonly used high-end processes Ni/Au, Ni/Pd/Au, and Pd/Au gold deposition is employed. Different types of gold electrolytes are available in the market, catering to varying target thicknesses. These electrolytes exhibit different plating mechanisms, ranging from fully immersion reaction types to mixed reaction types. Mixed reaction type gold electrolytes employ a combination of immersion and autocatalytic deposition behavior. The latest generation of mixed reaction gold electrolytes, characterized by a heightened level of autocatalytic reaction, offer significant technical advantages by enabling the deposition of thick gold layers onto nickel and palladium surfaces without compromising the integrity of the nickel layer during plating. However, due to their increased autocatalytic properties, these electrolytes necessitate continuous dosing of stabilizer components, typically based on potassium cyanide, to maintain stability. Therefore, the plating mechanism of the gold electrolyte was thoroughly examined, elucidating the roles of cyanide and the reducing components. Given the associated health risks with handling potassium cyanide, alternative stabilizer components were explored and identified to effectively stabilize the gold in the plating electrolyte. As a result, in this paper a novel gold electrolyte with autocatalytic properties is introduced. It is capable of depositing high layer thicknesses and defect-free ENIG (Electroless Nickel Immersion Gold) deposits. The stabilizer used in this electrolyte is non-toxic and does not contain free cyanide, ensuring an environmentally friendly approach. Extensive testing was conducted for Ni/Au, Ni/Pd/Au, and Pd/Au deposits, comparing the new electrolyte's performance results with the current industry-standard processes. The evaluation focused on solder joint reliability, nickel layer corrosion, thickness distribution, and characterization of the gold deposit. An easy, safe, and stable processing, with bath lifetimes up to 20 MTO at a gold concentration of 0.6 g/l could be proven with this new electrolyte.

Cytokine-mediated systemic inflammation after open thoracoabdominal aortic aneurysm (TAAA) repairs plays a pivotal role in disrupting circulatory homeostasis, potentially leading to organ dysfunction. The bioactive form of adrenomedullin (bio-ADM) is a peptide hormone with immunomodulatory and vasomotor effects, making it a potential diagnostic agent in these cases. This retrospective, bicentric study, conducted between January 2019 and December 2022, recruited 36 elective open TAAA repair patients in two German centres. Serum and plasma samples were collected at multiple time points to measure bio-ADM levels. The primary objective was to evaluate the association of bio-ADM levels with the onset of acute respiratory distress syndrome (ARDS), with secondary endpoints focusing on mortality and SIRS-related morbidity. Results showed a significant association between postoperative bio-ADM levels (12–48 h after surgery) and the onset of ARDS (p < .001), prolonged ventilation (p = .015 at 12h after surgery), atrial fibrillation (p < .001), and mortality (p = .05 at 24h). The biomarker was also strongly associated with sepsis (p = .01 at 12 h) and multi-organ dysfunction syndrome (MODS) (p = .02 at 24 h after surgery). The study underscores the potential utility of bio-ADM as a diagnostic tool for identifying patients at risk of postoperative complications following open TAAA repairs.

Abstract A detailled study of the impact of stereoelectronic effects of olefins in the Matsuda‐Heck‐reaction was addressed by kinetic studies. In addition to the stereoelectronic effects of the olefins used, their influence on the formation of the catalytic Pd colloids was also investigated. Depending on the olefin used, different particle size distributions were obtained on the one hand and, on the other hand, inhibition effects due to adsorption of the olefins on the Pd colloids were observed. Based on these findings, it was possible to optimize reaction conditions for the respective olefins. The presented kinetic data were supplemented by STEM‐measurements.

&lt;p&gt;Was zeichnet ein harmonisches Notenbild aus, wie sind die Gr&ouml;&szlig;enverh&auml;ltnisse einzelner Symbole im Druck? Wir haben tausende Seiten von Musikdrucken gescannt und sie mit unserer selbstentwickelten OMR-Software analysiert. So sind wir in der Lage sehr pr&auml;zise Aussagen &uuml;ber Gr&ouml;&szlig;en und Gr&ouml;&szlig;enverh&auml;ltnisse einzelner Symbole zu treffen. Ersten Ergebnisse sollen auf einem Poster pr&auml;sentiert werden und uns bei der digitalen Transformation des klassischen Notensatzes helfen ein ansprechenderes Layout zu erzielen.&lt;/p&gt; &lt;p&gt;Ein Beitrag zur 8. Tagung des Verbands &quot;Digital Humanities im deutschsprachigen Raum&quot; - DHd 2022 Kulturen des digitalen Ged&auml;chtnisses.&lt;/p&gt;