Versatile Lead-Free Solder Electroplating Products for Advanced Bumping Technologies

2014 ◽  
Vol 2014 (DPC) ◽  
pp. 001603-001621
Author(s):  
Inho Lee ◽  
Regina Cho ◽  
Lou Grippo ◽  
Yen-Lin Taylor ◽  
Wayne Baldelli ◽  
...  

Lead-free SnAg solder bumps deposited by electroplating are used extensively in high volume production lines for a number of new bumping technologies including C4 bumps, Cu pillars capped with SnAg solder and 3D microbumps. New bumping technologies present their challenging requirements such as tightly controlled thickness uniformity, alloy composition uniformity and avoidance of reflow voids to create high yields and low defects. To meet these requirements, SnAg plating chemistry must deliver strong performance over a wide range of applications. Traditional device manufacturers, wafer foundry companies and Outsourced Assembly and Test (OSAT) companies are manufacturing a number of different types of bumped wafers in their production lines; a diverse range of die design and pattern densities, thin and thick resist film wafers, mushroom and in-via plating, and wide range of plating rate. The variety and complexity of bumping wafers have challenged SnAg plating chemistries to meet tight requirements in terms of running cost saving and high production yield. Hence, development of versatile and robust chemistries for electroplating is critical to overcome these challenges In view of all these challenges and unmet needs in the market, Dow focused its efforts on developing a brand-new additive system for SnAg plating. On the one hand, we tapped into our know-how on solder plating to establish correlations between various types of end-user requirements and experiences to fundamental electrochemistry response. On the other hand, 300mm in-house plating and process tools are leveraged to speed up the feedback process and provide pilot run data. At the end, this highly iterative approach enabled us to optimize the performance of the chemistry without sacrifice on design space. In this paper, we will discuss next generation of SnAg electroplating products capable of achieving versatile performance requirements over a wide range of applications. The bump height WID co-planarity% ((hmax-hmin)/2havg ×100) was achieved less than ±5% over the wide range of current density from 4 ASD to 12 ASD. Smooth surface morphology, narrow Ag alloy composition distribution less than ±0.2% across the 300mm wafers, and reflow void free were observed. An optimized formulation of the next generation SnAg products was successfully demonstrated plating capability on various bumping technologies such as C4 bumping, Cu pillars capped SnAg solders and micro bumps meeting plating requirements.

Polymers ◽  
2021 ◽  
Vol 13 (10) ◽  
pp. 1566
Author(s):  
Oliver J. Pemble ◽  
Maria Bardosova ◽  
Ian M. Povey ◽  
Martyn E. Pemble

Chitosan-based films have a diverse range of potential applications but are currently limited in terms of commercial use due to a lack of methods specifically designed to produce thin films in high volumes. To address this limitation directly, hydrogels prepared from chitosan, chitosan-tetraethoxy silane, also known as tetraethyl orthosilicate (TEOS) and chitosan-glutaraldehyde have been used to prepare continuous thin films using a slot-die technique which is described in detail. By way of preliminary analysis of the resulting films for comparison purposes with films made by other methods, the mechanical strength of the films produced was assessed. It was found that as expected, the hybrid films made with TEOS and glutaraldehyde both show a higher yield strength than the films made with chitosan alone. In all cases, the mechanical properties of the films were found to compare very favorably with similar measurements reported in the literature. In order to assess the possible influence of the direction in which the hydrogel passes through the slot-die on the mechanical properties of the films, testing was performed on plain chitosan samples cut in a direction parallel to the direction of travel and perpendicular to this direction. It was found that there was no evidence of any mechanical anisotropy induced by the slot die process. The examples presented here serve to illustrate how the slot-die approach may be used to create high-volume, high-area chitosan-based films cheaply and rapidly. It is suggested that an approach of the type described here may facilitate the use of chitosan-based films for a wide range of important applications.


What did it mean to be a man in Scotland over the past nine centuries? Scotland, with its stereotypes of the kilted warrior and the industrial ‘hard man’, has long been characterised in masculine terms, but there has been little historical exploration of masculinity in a wider context. This interdisciplinary collection examines a diverse range of the multiple and changing forms of masculinities from the late eleventh to the late twentieth century, exploring the ways in which Scottish society through the ages defined expectations for men and their behaviour. How men reacted to those expectations is examined through sources such as documentary materials, medieval seals, romances, poetry, begging letters, police reports and court records, charity records, oral histories and personal correspondence. Focusing upon the wide range of activities and roles undertaken by men – work, fatherhood and play, violence and war, sex and commerce – the book also illustrates the range of masculinities that affected or were internalised by men. Together, the chapters illustrate some of the ways Scotland’s gender expectations have changed over the centuries and how, more generally, masculinities have informed the path of Scottish history


This book opens a cross-regional dialogue and shifts the Eurocentric discussion on diversity and integration to a more inclusive engagement with South America in private international law issues. It promotes a contemporary vision of private international law as a discipline enabling legal interconnectivity, with the potential to transcend its disciplinary boundaries to further promote the reality of cross-border integration, with its focus on the ever-increasing cross-border mobility of individuals. Private international law embraces legal diversity and pluralism. Different legal traditions continue to meet, interact and integrate in different forms, at the national, regional and international levels. Different systems of substantive law couple with divergent systems of private international law (designed to accommodate the former in cross-border situations). This complex legal landscape impacts individuals and families in cross-border scenarios, and international commerce broadly conceived. Private international law methodologies and techniques offer means for the coordination of this constellation of legal orders and value systems in cross-border situations. Bringing together world-renowned academics and experienced private international lawyers from a wide range of jurisdictions in Europe and South America, this edited collection focuses on the connective capabilities of private international law in bridging and balancing legal diversity as a corollary for the development of integration. The book provides in-depth analysis of the role of private international law in dealing with legal diversity across a diverse range of topics and jurisdictions.


2020 ◽  
Author(s):  
Aleksandra Balliu ◽  
Aaltje Roelofje Femmigje Strijker ◽  
Michael Oschmann ◽  
Monireh Pourghasemi Lati ◽  
Oscar Verho

<p>In this preprint, we present our initial results concerning a stereospecific Pd-catalyzed protocol for the C3 alkenylation and alkynylation of a proline derivative carrying the well utilized 8‑aminoquinoline directing group. Efficient C–H alkenylation was achieved with a wide range of vinyl iodides bearing different aliphatic, aromatic and heteroaromatic substituents, to furnish the corresponding C3 alkenylated products in good to high yields. In addition, we were able show that this protocol can also be used to install an alkynyl group into the pyrrolidine scaffold, when a TIPS-protected alkynyl bromide was used as the reaction partner. Furthermore, two different methods for the removal of the 8-aminoquinoline auxiliary are reported, which can enable access to both <i>cis</i>- and <i>trans</i>-configured carboxylic acid building blocks from the C–H alkenylation products.</p>


2019 ◽  
Author(s):  
Andrew Romine ◽  
Kin Yang ◽  
Malkanthi Karunananda ◽  
Jason Chen ◽  
Keary Engle

A weakly coordinating monodentate heteroaryl thioether directing group has been developed for use in Pd(II) catalysis to orchestrate key elementary steps in the catalytic cycle that require conformational flexibility in a manner that is difficult to accomplish with traditional strongly coordinating directing groups. This benzothiazole thioether, (BT)S, directing group can be used to promote oxidative Heck reactivity of internal alkenes providing a wide range of products in moderate to high yields. To demonstrate the broad applicability of this directing group, arene C–H olefination was also successfully developed. Reaction progress kinetic analysis provides insights into the role of the directing group in each reaction, which is supplemented with computational data for the oxidative Heck reaction. Furthermore, this (BT)S directing group can be transformed into a number of synthetically useful functional groups, including a sulfone for Julia olefination, allowing it to serve as a “masked olefin” directing group in synthetic planning. In order to demonstrate this synthetic utility, natural products (+)-salvianolic acid A and salvianolic acid F are formally synthesized using the (BT)S directed C–H olefination as the key step.


2019 ◽  
Author(s):  
Keren Gueta ◽  
Yossi Harel-Fisch ◽  
Sophie D. Walsh

BACKGROUND Despite the low utilization rates of substance use and related disorders services, and the ability of internet-based interventions for substance use and related disorders (IBIS) to address challenges related to service engagement, limited attention has been placed on the processes for the accommodation of these interventions to diverse cultural settings. OBJECTIVE The purpose of this study was to develop a conceptual framework for the cultural accommodation of IBIS across populations, settings, and countries. METHODS A pilot study of cultural accommodation of an existing internet intervention for alcohol use (Down Your Drink (DYD)), focus groups and daily online surveys of prospective consumers (N=24) and interviews with experts (N=7) in the substance abuse treatment field were conducted. RESULTS Thematic analysis revealed a wide range of themes identified as needing to be addressed in the process of DYD accommodation. It also emphasized that accommodation needs to incorporate both technical and contents themes, shaped by both the general Israeli cultural as well as by the specific Israeli drinking subculture. A combined mixed emic–etic theoretical approach incorporating the pilot findings together with a scoping literature review was employed to develop a framework for cultural accommodation of IBIS. A comprehensive framework for cultural accommodation of IBIS is introduced consisting of five chronological stages of IBIS accommodation and four dimensions of accommodation. CONCLUSIONS The proposed framework can serve as a guide for the cultural accommodation of existing IBIS across a diverse range of cultural and geographical settings thus augmenting the ecological validity of IBIS and reducing health disparities worldwide.


2006 ◽  
Vol 519-521 ◽  
pp. 795-802 ◽  
Author(s):  
Dominique Daniel ◽  
Gilles Guiglionda ◽  
Pierre Litalien ◽  
Ravi Shahani

Cost-efficient designs of aluminum autobody structures consist mainly of stampings using conventional technology. Progress in metallurgy and forming processes has enabled aluminum body panels to achieve significant market share, particularly for hoods. Fast bake hardening alloys with better hemming performance were developed for improved outer panel sheet products. Specific guidelines for handling and press working were established to form aluminum panels using similar schedules and production lines as steel parts. Stamping productivity was improved by optimization of the trimming process to reduce sliver/particle generation and resulting end-of-line manual rework. Both hemming formability and trimming quality not only depend on tooling setup but also on microstructural features, which govern intrinsic alloy ductility. Targets for the next high volume aluminum car body applications, such as roof panels and doors, require higher strength and/or better formability. The challenges of complex stampings can be met with optimized alloys and lubricants, with improved numerical simulation to fine-tune stamping process parameters, and with the introduction of new technologies. Warm forming was examined as a potential breakthrough technology for high volume stamping of complex geometries.


2021 ◽  
Author(s):  
Qiu-Hong Huang ◽  
Qian-Yi Zhou ◽  
Chen Yang ◽  
Li Chen ◽  
Jin-Pei Cheng ◽  
...  

A highly efficient desymmetrizing asymmetric bromination of bisphenol phosphine oxides was developed, providing a wide range of chiral bisphenol phosphine oxides and bisphenol phosphinates with high yields and enantioselectivities.


Studies of the chemistry of metal cluster complexes and, in particular, their reactions with small organic molecules, have been confined to relatively few systems. Among the reasons for this are: (i) not many clusters are easily synthesized in high yields; (ii) their reactions often give a multitude of products that are difficult to separate and characterize; (iii) the conditions required to bring about reactions often lead to fragmentation of the cluster into lower nuclearity (often mononuclear) species. One cluster whose chemistry has been extensively studied is [Os 3 H 2 (CO) 10 ]. This can be synthesized in high yields from [Os 3 (CO) 12 ] + H 2 (Knox et al. 1975) and reacts readily under mild conditions with a wide range of electron-donor molecules by virtue of its coordinative unsaturation (Shapley et al. 1975; Deeming & Hasso 1976; Adams & Golembeski 1979). Formally, one may consider that a metal—metal double bond is present, which is reduced to a single bond on coordination of an additional two-electron donor ligand such as an organophosphine. The presence of metal—hydrogen bonds in this cluster and the cluster’s ability to coordinate organic substrates enable it to undergo a wide variety of insertion reactions, leading to products that may be regarded as intermediates in the reduction of organic molecules by clusters (Deeming & Hasso 1975; Keister & Shapley 1975).


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