Solderability Challenges in Emerging BGA Packages

2014 ◽  
Vol 2014 (DPC) ◽  
pp. 000913-000929
Author(s):  
Maria Durham ◽  
Yan Liu ◽  
Andy Mackie
Keyword(s):  
Value Added ◽  
Bga Packages ◽  
One Step ◽  
Process Cost

The final step of reflowing solder spheres to solderable pads on the bottom of substrates in FCBGA, CSP, and WLCSP packages is often considered to be a trivial step. However, with the increasing complexity and number of assembly processes taken prior to this final soldering step, the formation of a reliable final joint is far from certain. In order to eliminate this problem, many OSATs and ODMs are adopting the non-value-added process of prefluxing, reflowing, cleaning, and drying substrates immediately prior to the final ball-attach process. This paper details the sequence of processes seen in typical BGA assembly, and examines the effects of each set of prior processes on the solderability of the final pad. It also details investigations of the solderable surface and metallurgy of the substrate pad. The introduction of a “one-step” pin-transfer ball-attach flux is shown to be a means of reducing both process cost and time, and also reducing the risk of significant warpage in the finished package.

Emerging Flux Challenges for BGA Packages

2016 ◽  
Vol 2016 (DPC) ◽  
pp. 001359-001390
Author(s):  
Maria Durham ◽  
Andy Mackie ◽  
Jason Chou
Keyword(s):  
Solder Joint ◽  
Failure Modes ◽  
Value Added ◽  
Ball Grid Array ◽  
Deposition Process ◽  
Testing Methods ◽  
Bga Packages ◽  
Bga Package ◽  
One Step ◽  
Process Cost

The formation of a Ball Grid Array (BGA) solder joint is critical for a BGA package where typically a flux deposition process is used. Reflowing solder spheres to solderable pads on the bottom of substrates in standard BGA, FCBGA, CSP, and similar packages is considered to be a trivial step: a specialized BGA flux is usually pin-transferred onto the pads, followed by balldrop onto the substrate. However, with the increasing complexity and number of assembly processes taken prior to this final step, the formation of a reliable final joint is far from certain. In order to eliminate variability, many OSATs and ODMs use the so-called “two step” (double fluxing) approach, which is comprised of the non-value-added extra processes of prefluxing, reflowing, cleaning, and drying substrates immediately prior to the final flux-based ball-attach process. This paper details the sequence of processes seen in typical FCBGA assembly, and examines the effects of each set of prior processes on the solderability of the final pad. The introduction of a “one-step” pin-transfer ball-attach flux is shown to be a means of reducing both process cost and time, and also reducing the risk of increased warpage in the finished package. The paper also investigates the solderable surface and metallurgy of the substrate pad. The variety of new and emerging failure modes for the BGA process as well as the different testing methods for the materials will also be discussed.

Waldpolitischer Jahresrückblick 2010 | Annual review of swiss forest policy 2010

2011 ◽  
Vol 162 (5) ◽  
pp. 137-145 ◽  
Author(s):  
Willi Zimmermann
Keyword(s):  
Spatial Planning ◽  
Forest Conservation ◽  
Forest Policy ◽  
Value Added ◽  
Political Agenda ◽  
Annual Review ◽  
Forest Law ◽  
One Step ◽  
Climate Convention ◽  
Article 5

In 2010, there were no major forest policy issues that attracted media attention. The year 2010 was rather marked by the preparation of decisions “offstage” and by recurring administrative implementation activities. The partial revision of the forest law, which has been launched, can be regarded as special, because it is not a routine affair: the Committee for the Environment, Spatial Planning and Energy of the Council of States decided to revise particularly article 7 (compensation for deforestation) and article 10 (assessing forest status) of the forest law, and thus loosen the strict regime for forest conservation. Concerning the sectoral policies related to forest, the parliament took the law on spatial planning (RPG) one step further towards its revision. With the proposed revision of the spatial planning law's article 5 (value-added charge) a forest policy relevant article is now up for discussion. Different forest relevant topics on the international political agenda were discussed during the two international conferences on biodiversity and climate convention just as during the treatment of the alpine and the landscape convention. Next year the discussions will presumably be about the future forest conservation policy.

scholarly journals Computational and experimental investigations of one-step conversion of poly(carbonate)s into value-added poly(aryl ether sulfone)s

2016 ◽  
Vol 113 (28) ◽  
pp. 7722-7726 ◽  
Author(s):  
Gavin O. Jones ◽  
Alexander Yuen ◽  
Rudy J. Wojtecki ◽  
James L. Hedrick ◽  
Jeannette M. García
Keyword(s):  
High Performance ◽  
Density Functional ◽  
Value Added ◽  
Single Step ◽  
Nucleophilic Attack ◽  
Experimental Investigations ◽  
Aryl Ether ◽  
One Step ◽  
Poly Carbonate

It is estimated that ∼2.7 million tons poly(carbonate)s (PCs) are produced annually worldwide. In 2008, retailers pulled products from store shelves after reports of bisphenol A (BPA) leaching from baby bottles, reusable drink bottles, and other retail products. Since PCs are not typically recycled, a need for the repurposing of the PC waste has arisen. We report the one-step synthesis of poly(aryl ether sulfone)s (PSUs) from the depolymerization of PCs and in situ polycondensation with bis(aryl fluorides) in the presence of carbonate salts. PSUs are high-performance engineering thermoplastics that are commonly used for reverse osmosis and water purification membranes, medical equipment, as well as high temperature applications. PSUs generated through this cascade approach were isolated in high purity and yield with the expected thermal properties and represent a procedure for direct conversion of one class of polymer to another in a single step. Computational investigations performed with density functional theory predict that the carbonate salt plays two important catalytic roles in this reaction: it decomposes the PCs by nucleophilic attack, and in the subsequent polyether formation process, it promotes the reaction of phenolate dimers formed in situ with the aryl fluorides present. We envision repurposing poly(BPA carbonate) for the production of value-added polymers.

Extraction and value-added utilization of alumina from coal fly ash via one-step hydrothermal process followed by carbonation

2021 ◽  
Vol 323 ◽  
pp. 129174
Author(s):  
Pengxu Cao ◽  
Guanghui Li ◽  
Hao Jiang ◽  
Xin Zhang ◽  
Jun Luo ◽  
...  
Keyword(s):  
Fly Ash ◽  
Coal Fly Ash ◽  
Hydrothermal Process ◽  
Value Added ◽  
One Step

scholarly journals A Three Methods Proactive Improvement Model for Buildings Construction Processes

2020 ◽  
Vol 12 (10) ◽  
pp. 4335
Author(s):  
Abdul-Aziz Banawi ◽  
Alia Besné ◽  
David Fonseca ◽  
Jose Ferrandiz
Keyword(s):  
Environmental Impact ◽  
Six Sigma ◽  
Environmental Performance ◽  
Value Added ◽  
Process Performance ◽  
Measuring Process ◽  
Lean Principles ◽  
One Step ◽  
Overall Performance

This paper proposes a proactive model to improve the overall performance of construction processes. The main advantage is that potential waste and associate impacts could be identified in the early stages of a project before the construction phase. To accomplish that, the model combines three methods; Lean-to identify waste, Green to assess environmental impact, and Six-Sigma to measure and improve process performance (LG6). The LG6 model helps in evaluating processes one step at a time, identifying consumed resources, analyzing the environmental performance of all steps as well as highlighting generated impacts, applying improving alternatives if needed, and measuring process performance for evaluation. The functionality of LG6 is illustrated through a case study of woodpiles installation. In this case study, the LG6 model identified four steps out of eight that are considered potential waste or (non-value-added steps) according to the Lean principles. As a result, the LG6 model helped in reducing impact by 9% and expenses by 1%. The LG6 model can help to improve the performance of construction processes and reduces unnecessary waste.

scholarly journals Highly efficient single-step pretreatment to remove lignin and hemicellulose from softwood

BioResources ◽  
2019 ◽  
Vol 14 (2) ◽  
pp. 3567-3577
Author(s):  
Irma Bernal-Lugo ◽  
Carmen Jacinto-Hernandez ◽  
Miquel Gimeno ◽  
C. Carmina Montiel ◽  
Fausto Rivero-Cruz ◽  
...  
Keyword(s):  
Value Added ◽  
Enzymatic Digestion ◽  
Single Step ◽  
Glucose Yield ◽  
Highly Efficient ◽  
First Case ◽  
Hemicellulose Removal ◽  
One Step ◽  
Low Glucose ◽  
Hydrolysis Of

The use of lignocellulosic softwood residues as feedstock for the production of bioethanol and other value-added chemical products has been limited by its high recalcitrance. Alkaline or organosolvent pretreatments have been used to remove recalcitrance in softwoods. Although these methods partially remove lignin and hemicellulose, they also result in low glucose recovery. In the first case, there is low cellulose hydrolizability, and in the second, there is a loss of cellulose. This study evaluated both methods combined into one step: alkaline hydrolysis of the biomass in the presence of an organosolvent. Different conditions of temperature and residence times were assayed. The efficiency of these conditions was quantified as the percentage of lignin and hemicellulose removed from the biomass without loss of cellulose. The substrate produced with the most efficient conditions removed 91% of the lignin and 89.1% of the hemicellulose with no loss of cellulose. Enzymatic hydrolysis of this biomass was 90% to 95%, with a substrate concentration of 3% and with five filter paper units per gram of cellulose (FPU/g cellulose). These results indicated that this one-step alkaline-organsolvent process, applied as a pretreatment to softwood, allows highly efficient lignin and hemicellulose removal. 100% of cellulose was recovered, and there was between 90 and 95% glucose yield after enzymatic digestion.

scholarly journals Process-cost analysis of productivity and wages in agro-industrial processing organizations

2020 ◽  
Vol 217 ◽  
pp. 09002
Author(s):  
Oksana Pirogova ◽  
Roman Nuzhdin ◽  
Nadezhda Kondrashova ◽  
Oksana Lukina
Keyword(s):  
Cost Analysis ◽  
Labor Productivity ◽  
Value Added ◽  
Industrial Complex ◽  
Industrial Processing ◽  
Key Stakeholders ◽  
Process Cost ◽  
Processing Organizations ◽  
Assessment Procedures ◽  
Dynamic Ratio

Process-cost analysis involves the implementation of appraisal procedures at each stage of adding value, which is considered as the main source of achieving the interests of personnel, owners and the state. The main goal of this study is to verify the existing methodological approaches to assessing the labor productivity of personnel in processing organizations of the agro-industrial complex, to assess the dynamic ratio of productivity and wages, based on methodologically justified assessment procedures that ensure the implementation of the advantages of process-cost analysis and eliminate the disadvantages of traditional methods. In order to improve the analytical suitability of the results of the process-cost analysis of labor results, three areas of key stakeholders’ interest are identified, for each of which corrective operations are provided that provide not only the possibility of a retrospective analysis, but also predicting the possibility of parity of interests. Based on the results obtained, it was concluded that the share of value added in total revenues is low, the level of wages is unreasonable and, consequently, significant disparities in the distribution of value added. The inconsistency of the criterial assessment of the dynamic ratio of labor productivity and its payment in modern conditions has been proved.

scholarly journals Curación de contenidos científicos en tiempos de fake science y Covid-19: una aproximación entre las ciencias de la información y la comunicación

2020 ◽  
pp. 281-289
Author(s):  
Alexandre López-Borrull ◽  
Candela Ollé
Keyword(s):  
Peer Review ◽  
Scientific Information ◽  
Value Added ◽  
Interdisciplinary Approach ◽  
Redes Sociales ◽  
Health Crisis ◽  
One Step ◽  
The Media ◽  
False News ◽  
The Impact

Content curation as a method of tackling misinformation offers some obvious advantages when generating value-added content that can help to reduce the impact and damage that false news can cause. If this takes place with specialized, e.g., scientific, information, it has even greater value. In these times of infodemic as defined by the WHO as part of the health crisis, the need for accurate and timely information may be more important than ever. Research is presented on the type of processes and which actors can help in the verification and filtering of unwanted information. The role that the media, verifiers, and social networks have in this process has been studied. The results point to the need for an interdisciplinary approach to scientific disinformation. Likewise, it is considered appropriate to work not only with a verification viewpoint (which could be more or less covered by peer review), but also to understand that to reverse false content it is necessary to go one step further by selecting and creating high-quality content and trying to counter false information. Resumen La curación de contenidos como método de trabajo ante la desinformación presenta algunas ventajas evidentes cuando se generan contenidos de valor añadido que pueden ayudar a remitir el impacto y daño que una noticia falsa puede llevar a cabo. Si ello tiene lugar con una información especializada como la científica tiene un mayor valor. En estos momentos de infodemia como define la OMS parte de la crisis sanitaria, la necesidad de información veraz y oportunamente divulgada puede ser más importante que nunca. Se presenta la investigación sobre qué tipo de procesos y qué actores pueden ayudar en los procesos de verificación y filtro de información no deseada. Se ha estudiado el papel que los medios de comunicación, los verificadores y las redes sociales tienen en este proceso. Los resultados apuntan a que se vislumbra la necesidad de una aproximación interdisciplinar a la desinformación científica. Asimismo, se estima oportuno trabajar no solamente con una visión de verificación (que podría estar más o menos cubierta por el peer-review), sino por entender que para revertir contenido falso es necesario dar un paso más, seleccionar y crear contenidos de calidad y intentar contrarrestar la información falsa.

Catalytic Sulfone Upgrading Reaction with Alcohols via Ru(II)

2019 ◽  
Author(s):  
Tomas Vojkovsky ◽  
Shubham Deolka ◽  
Saiyyna P. Stepanova ◽  
Michael C. Roy ◽  
Eugene Khaskin
Keyword(s):  
Functional Groups ◽  
Secondary Alcohol ◽  
Value Added ◽  
Catalytic Dehydrogenation ◽  
Reaction Conditions ◽  
Stoichiometric Amount ◽  
Reaction Proceeds ◽  
One Step ◽  
Value Added Products

<a>Sulfones and sulfonamides with an α-CH bond can be easily alkylated by aliphatic alcohols to add the carbon skeleton of the alcohol via a one-step, Ru(II) catalyzed redox neutral reaction. The reaction requires a sub-stoichiometric amount of base and produces only water as a byproduct. A number of pharmaceutically relevant functional groups such as piperidine, morpholine, etc. are well tolerated under the reaction conditions to give higher value-added products in one step from widely available substrates. The reaction proceeds through a sulfone carbanion addition to an in-situ generated aldehyde formed via catalytic dehydrogenation and subsequent catalyst mediated replacement of the secondary alcohol by hydrogen.</a>

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