By Topic

Asian Green Electronics, 2004. AGEC. Proceedings of 2004 International IEEE Conference on the

Date 2004

Filter Results

Displaying Results 1 - 25 of 66
  • Reliability of ACF joint using bumpless chip after reflow process

    Publication Year: 2004 , Page(s): 235 - 239
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1455 KB) |  | HTML iconHTML  

    The influence of the reflow process on the reliability of anisotropic conductive film (ACF) joints using bumpless chips was investigated. The contact resistance of the ACF joint was found to increase as the peak reflow temperature increased. The results also indicated bump height was not the controlling factor for the ACF joint reliability. During reliability test, bumpless chips proved to be unreliable owing to the inherent behavior of aluminum under a wet environment (corrosion-degradation). The moisture ingression into the ACF can lead to unstable reliability of the joint. Moreover, the ACF showed degradation in both chemical and physical properties, including modulus reduction, polymer hydrolysis, and surface swelling. In reflow soldering after temperature/humidity test, the ACF joint reliability was further deteriorated due to thermal-induced stress of different component CTE and hydroscopic swelling-induced stress of the epoxy. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Closing the loop of printed-wire-boards and electronic devices: experiences from automatic disassembling as an input for manufacturers

    Publication Year: 2004 , Page(s): 182 - 185
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1476 KB) |  | HTML iconHTML  

    Due to the fast pace of technological innovation, and the consequent shortening lifetimes of electronic products, particularly ICT equipment, a,flexible semi-automatic disassembling cell "Σ! 1592 - Disassembly Factory" for extracting components from printed wire boards (PWB) has been developed. Based on these disassembling experiences design criteria for a re-use optimized structure of PWBs and electronic components have been defined in order to maximize the benefit for economy and environment. If industry becomes aware of the elaborated design criteria and uses these investigations, number of reusable components can be achieved and enhanced significantly hand in hand with the improved quality and positive feedback regarding landfill volume and depletion of primary materials. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Properties and reliability of SnZn-Based lead-free solder alloys

    Publication Year: 2004 , Page(s): 38 - 41
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1447 KB) |  | HTML iconHTML  

    In green electronics, e.g. hybrids and MEMS (micro electromechanical systems) tin-lead-solder materials are substituted by lead-free solder materials. Several alloys could be used, for example SnCu, SnCuAg, or SnBi alloys, depending on the product and the working temperature. range between 205-216 °C. Using tin-zinc solder materials the needed heat is smaller, electronic components will not be overheated and a high compatibility of all manufacturing processes could be assumed. On the other hand early reports in the literature indicate a sensitivity to intercrystalline corrosion. This work deals with the handling and the reliability of the eutectic Sn91Zn9 and the Sn89Zn8Bi3 alloy. The pad metallization of the substrate was Cu/Ni/Au or Cu and the metallization of the used electronic components was Sn, NiPd and Sn96.5Ag3.5. Shear tests before and after thermal cycling, creep tests at high homologous temperatures, metallographic investigations and migration tests were done after soldering to determine the reliability of these solder joints. A Sn60Pb40 solder alloy was used as a reference. The used solder profiles of a vapour-phase and a convective reflow soldering lead to good wettability of the liquid solder The solder joints show a higher shear force than the tin-lead alloy and the decrease of the shear force due to thermal cycles was lower than the tin-lead solder joints. The tin-zinc-alloy shows a higher creep resistance and a lower migration behaviour than the tin-lead alloy. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Scalable distributed architecture of the terabit router

    Publication Year: 2004 , Page(s): 186 - 189
    Cited by:  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1470 KB) |  | HTML iconHTML  

    Aggressive research on terabit per second networks has led to dramatic improvements in network transmission speeds. One result of these improvements has been to put pressure on router technology to keep pace. There is more urgent need to research and study terabit (1012 bit) router. Traditional routes using shared-bus and central processing unit cannot do it. So how to support the terabit per second data speed is a great challenge for traditional router architecture. In this article, the recent years' new achievements in terabit routers are summarized, the new functions of terabit routers are introduced, and the distributed architecture of new generation super high speed terabit router are analyzed, which put emphasis on the multi-dimensional switching architecture. At last, The prospect of terabit router plays the final role for the paper. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Worldwide trends impacting green electronic products

    Publication Year: 2004 , Page(s): 9 - 11
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1357 KB)  

    First Page of the Article
    View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • A fluxless flip chip bonding for VCSEL arrays using silver coated indium solder bumps

    Publication Year: 2004 , Page(s): 110 - 116
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1683 KB) |  | HTML iconHTML  

    Alloys of lead-tin system are the most common solder alloys used today. However, there are environmental and health issues concerning the toxicity of lead present in these lead-tin solder alloys. Also the flux residue removal is mandatory and leads to environment threats. More important, the use of flux may contaminate the optically active surface by organic residue leftover, and a conventional cleaning method may not be effective for optoelectronic assemblies. Therefore, it is necessary to look for fluxless soldering processes for soldering optoelectronic systems. In the present study, we have conducted low-temperature flip-chip bonding of vertical-cavity surface-emitting laser (VCSEL) arrays on a glass substrate that provides propagation paths of laser beams and also supports a polymeric waveguide. Using indium solder bumps, an optimum condition of flip-chip bonding is determined as a heating temperature of 150°C and a pressure of 500gf. The fracture occurs between the indium solder bump and the VCSEL chip pad during the die shear test. It is inferred that both the low bonding temperature and the oxide layer which is formed on the surface of the indium solder prevented the bump from interacting with the chip pad. To decrease the melting temperature of the indium solder and protect it from oxidation without using flux, we try also coating of a thin silver layer onto the indium surface. An eutectic reaction occurs at 97 wt.% of In with eutectic point of 144°C and the outer silver layer interacts with indium to form a AgIn2 compound layer due to the high interdiffusion coefficient. As a result, the thin silver layer coated on the solder bump is very effective to enhance the adhesion strength between the indium bump and the VCSEL chip pads by decreasing the melting temperature of the indium solder bump locally. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Environmental management in semiconductor and printed circuit board industry in India. Part I: Survey results and case studies

    Publication Year: 2004 , Page(s): 139 - 149
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1906 KB) |  | HTML iconHTML  

    During the 1990s electronics has assumed the role of providing a forceful leverage to the socio-economic and technological growth of developing society. The initial thinking that the IT & electronics manufacturing activities, involving high technologies would be clean and free from pollution problems, is no more valid today. As the electronics industry rapidly expanded it became evident that the diversity of the industry and its products could cause considerable environmental damage if not properly managed. The major impacts include pollution from manufacturing, waste disposal and use of toxic materials and chemicals that can cause damage to water, soil and air eventually polluting our Oceans and our Planet. In order to ameliorate the environmental impact from the hazardous processes and products, the IT & electronics sector has to adopt increased environmental safety standards. A systematic and integrated approach to environmental management is thus inescapable in the long run. Department of Information Technology in collaboration with United Nationals Development Programme (UNDP) has drawn up a National Programme on "Environmental Management in Semiconductor and Printed Circuit Board Industry in India" to foster environmental management and pollution prevention in Indian Electronics and IT industry. The implementation of this programme has been supported by National and International partners, such as Fraunhofer IZM, Germany, by training and consultancy, US EPA and industry in USA & Europe in providing the information about cleaner production technologies being practiced. The topic will be presented with two papers: Part I describes the Indian initiative on cleaner production technologies in communication, information and electronics sector, objectives and scope of the DIT project. The results of phase I activities of the DIT project cover the survey findings according to the general framework of electronics manufacturing in India and the role of domestic electronics industry in global supply chains. The technological status of electronics manufacturing and the main environmental aspects to be addressed are specified. Best available technologies and practices in Indian context are analyzed in detail. Best practice case studies presented in the paper cove- r examples from PCB and semiconductor industry. The case studies comprise material flow analysis for these specific technologies and environmental assessment. The part I paper concludes with an outlook on phase II activities of the DIT project. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Roadmap to green supply chain electronics: design for manufacturing implementation and management

    Publication Year: 2004 , Page(s): 169 - 173
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1475 KB) |  | HTML iconHTML  

    The green environment or environmental friendly has high important in today electronics business. The intense forces of customer, competitors as well as the government induced the electronics manufacturing rapidly implement the green process in their organization. In green manufacturing implementation, various factors must be prepared and well controlled in order to ensure the effectiveness. In this paper, we proposed the 6 basic requirements of preparation that can be grouped into product factors and environment factor. The result of research shows that the 5 factors of material, process, packaging, working environment and waste system are directly impact to the green management implementation. We also propose the green supply chain if the manufacturing promotes the same "Green Manufacturing System (GMS) to the lower tier supplier. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Environment-friendly PVD Al-plug process for submicron multilayer interconnection

    Publication Year: 2004 , Page(s): 92 - 95
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1398 KB) |  | HTML iconHTML  

    IC industries are now under heavy pressure to develop electronics that lessen the environmental pressure. Green electronics calls for more environment-friendly manufacturing processes. An aluminum reflow process for metallization simply employing a PVD cluster tool, instead of CVD-tungsten fixtures, was successfully applied to fabricate IC wafers of narrow line width. Compared with tungsten, aluminum plugs can be formed in vias and contacts by PVD method which contributes to no precursor and little by-products. It also benefits the environment by saving process steps and equipment. Moreover, unlike refractory metals, aluminum is among the selected materials for electronic products for its recyclability after disposal. This paper will show how this green process can realize multilayer interconnection in submicron scope that used to be achieved only by tungsten. Voids in contacts and vias are eliminated by the thermal diffusion of aluminum atoms. Different conditions including two-step process are used to treat device wafers. The step coverages of contacts are tested to investigate both temperature and power dependence of the ability of aluminum to diffuse into the void during reflow steps. The mechanism of reflow is demonstrated theoretically and experimentally. The optimal processing condition is. also obtained through the experiments. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Thermal and mechanical analysis of recycled glass filled PET for printer part

    Publication Year: 2004 , Page(s): 50 - 55
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1546 KB) |  | HTML iconHTML  

    Continuous and rapid technological advancement has dramatically improved the way we live. It also means that electronic products are being discarded faster than ever before. The increasing amount of electronic trash is definitely a growing pollution problem as more electronics join the league of waste stream in coming years. With every printing products sold, many more ink cartridges are produced. Ink cartridges are one of Hewlett Packard's key products. Because its large scale volume the impact that the product has on the environment requires attention. Product take back of used cartridges is necessary to provide our customers with an environmentally responsible end-of-life solution and also enables us to reduce our plastic waste. This paper presents the results on recycled glass reinforced Polyethylene Terephthalate (PET) usage in printer part. The recycled glass filled PET is compounded by Lavergne Group, Montreal, Canada. The stream of recycled PET feedstock is from 75% purified water bottle flake grade and 25% purified used ink cartridges from Hewlett Packard. Both are reprocessed to use on HP's printer model. Experimental studies were carried out to investigate the mechanical and thermal properties of the recycled glass-filled material. The experimental data obtained is then measured against comparable industrial data available on glass-filled PET product. Printer parts were subsequently molded and undergone product functional qualifications. Thermal analysis technique was applied to understand the findings from the qualification. The obtained thermograms from Differential Scanning Calorimetry provided quantitative and qualitative information about the physical and phase changes that involve endothermic or exothermic processes. These data will be extensively discussed in this paper. This study is a concerted industrial effort from several parties working on waste reduction opportunities. Not only will produce certain cost savings, it will also reflect our environmental pursuit towards the successful marriage of waste reduction without compromising quality and functionality. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Solder and adhesive free chip assembly using elastic chip sockets: concept, manufacture and preliminary investigations

    Publication Year: 2004 , Page(s): 12 - 17
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1568 KB) |  | HTML iconHTML  

    Flip Chip connections enormously reduces the amount of solder as compared to mounting packaged devices, apart from also offering superior high frequency properties and placement density. However, when assembling chips to substrates having different thermal expansion coefficient, the solder balls are exposed to strain, the more so the denser the connections (and consequently smaller balls), and the higher the power densities, resulting in wider temperature cycles. This will usually result in loss of contact reliability. Using other materials than solder or using underfills may partially improve the situation, but causes other problems. In order to test another concept maintaining or exceeding the excellent HF and density properties of conventional Flip Chip, while practically eliminating the thermal mismatch problems and providing effortless chip replacement, the Elastic Chip Socket was developed. Silicone elastomer was molded in a precision mold made using anisotropic etching of Si. These structures were subsequently metallized and the metal patterned using electro plated resist. So far functional chip sockets with pin densities of 45 000 pins per cm2 (22 500 simultaneously functional connections to a 7 x 7 mm die) and more have been achieved which endure multiple repeated matings and quick temperature cycling between -40 °C and +90 °C. The following is a summary of the group's achievement this far, Oct. 2003. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Lead free solder paste containing SnAgBiIn alloy: a preliminary study

    Publication Year: 2004 , Page(s): 123 - 126
    Cited by:  Papers (2)  |  Patents (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1484 KB) |  | HTML iconHTML  

    In this report, a preliminary investigation has been conducted on some lead free solder pastes containing Sn88Ag3.5Bi0.5In8 alloy. The wetting performances of these solder pastes on different substrates were studied under various reflow profiles. The test results of solder ball, slump and printing properties indicate that with a proper paste flux vehicle, lead free solder paste using Sn88Ag3.5Bi0.5In8 alloy may achieve a good performance. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Laser induced writing of conductive copper lines for electronic devices

    Publication Year: 2004 , Page(s): 174 - 176
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1416 KB) |  | HTML iconHTML  

    The direct writing of conductive copper lines on alumina substrates by means of a Nd/YAG-laser was investigated as an alternative to established thick-film and thin-film hybrid technology. Copper powder in the low micrometer range was sprayed as an aqueous dispersion on the surface of alumina substrates normally used for thick-film hybrids. With proper setting of the laser parameters, conductor lines with good adhesion and a relatively smooth surface were achieved. After removal of the excessive copper powder, the remaining copper particles acted as seeds for a subsequent electroless copper plating thus providing an electrical conductivity sufficient for electronic devices. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Business benefits from applied EcoDesign

    Publication Year: 2004 , Page(s): 200 - 205
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1584 KB) |  | HTML iconHTML  

    This paper describes the application of EcoDesign (environmentally conscious design) within the electronics manufacturing company Philips. How the process has matured from a case-by-case basis driven by single persons to becoming a standard part of the product creation process of most of the Philips' business units. Since it was first introduced, the EcoDesign process has gone through many changes, not only to deal with influences from the outside world such as regulation and voluntary industrial agreements but more importantly, to allow alignment with existing business procedures and business direction. The scope of the process has widened beyond the product to now include also the supply chain, the end of life and consumer behavior. This also means a much closer cooperation with stakeholders beyond the product developer; it also involves the purchasing department, market research and dialogue with recycling industry. One of the key processes supporting the EcoDesign process is environmental product benchmarking, comparing the Philips product with its direct commercial competitors. As the EcoDesign process, also this activity has matured over time, allowing more product benchmarks over time and at the same time improving the quality of the results. The results are now visible in examples of green marketing and communication as the Philips Consumer Electronics Internet site now displays examples of Green Flagship products. Furthermore, the benchmarking activity is now also used to provide valuable information on OEM products, and monitoring how competition is backing up claims related to their products' environmental performance. It is not surprising that in its recently revealed new environmental program, Philips again shows commitment to keep a focus on applying EcoDesign and more environmental product benchmarking. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Towards printed organic electronics

    Publication Year: 2004
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1251 KB) |  | HTML iconHTML  

    Summary form only given. Silicon integrated circuits (ICs) are wonderful for numerous microelectronic applications. But for large-area devices and low-cost microelectronic applications where high computer powers or switching speeds are not needed, they become unjustifiably and prohibitively expensive. Plastic ICs composed of organic transistors and components are attractive alternatives for these applications as they can potentially be manufactured at low cost by solution processes such as coating, stamping, printing, etc. No capital-intensive photolithographic clean-room setups are required. Fabricating ICs via jet printing is particularly efficient and environmentally friendly as it is a direct-write process, and is amenable to the productive reel-to-reel manufacturing protocols. Organic transistors are also compatible with flexible substrates, thus enabling fabrication of compact, lightweight, flexible, and structurally inspiring microelectronic products. The ability to directly integrate ICs with other electronic components via printing may also contribute to lowered manufacturing cost as some of the costly packaging processes can be eliminated. Organic semiconductor polymers are appealing active materials for low-cost thin film transistor designs. For low-cost manufacturing, both the solution processability of materials and their ability to be processed at ambient without detrimental effects are of paramount importance. However, most of the current semiconductor polymers are not stable enough to permit processing and device fabrication in ambient conditions to achieve the required functionalities. We describe here our work on the semiconductor polymer design, their synthesis and processing that have led to the fabrication of polymer thin film transistors in ambient conditions with excellent field-effect transistor properties. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • The impact of lead-free legislation exemptions on the electronics industry

    Publication Year: 2004 , Page(s): 26 - 37
    Cited by:  Papers (1)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (2072 KB) |  | HTML iconHTML  

    The European Parliament's Waste Electrical and Electronic Equipment legislation requires manufacturers to bear responsibility for the mandatory collection, reuse and recycling of electronics products. The Restriction of the use of Hazardous Substances in electrical and electronic equipment legislation mandates the substitution of lead and other hazardous substances in electronics products by July 2006. The lead-free legislation contains a number of exemptions. The impact of the lead-free legislation exemptions varies across different industry sectors and product categories. In this paper, we have outlined the underlying basis of the exemptions and analyzed the relevance and significance of these exemptions to the electronics industry. We then examined how various sectors of the electronics industry will be able to respond to the exemptions in their product development. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Novel epoxy/BaTiO3 composite embedded capacitor films embedded in organic substrates

    Publication Year: 2004 , Page(s): 68 - 73
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1516 KB) |  | HTML iconHTML  

    Embedded passive technology is an essential technology for further miniaturization and higher performance of electronic package systems. Polymer/ceramic composites have been of great interest as embedded capacitor materials, because they did combine not only the processability of polymers with high dielectric constant of ceramics but also good compatibility with printed circuit boards (PCBs). Novel embedded capacitor films (ECFs) were newly designed for low tolerance embedded capacitor fabrication for organic substrates. In terms of material formulation, ECFs are composed of specially formulated epoxy resin and latent curing agent. And in terms of coating process, a comma roll coating method is used for uniform film thickness in large area. In this paper, it is demonstrated that low tolerance (less than 5%) capacitor can be fabricated using ECFs, and properties of epoxy/BaTiO3 composite ECFs are reported. Fabrication process and various properties of ECFs such as dielectric constant, leakage current, adhesion strength, thereto-mechanical characteristics, reliability, and high frequency behavior up to 3 GHz will be presented. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Facilitating DfE in enterprises: the Taiwan Green Design Network

    Publication Year: 2004 , Page(s): 164 - 166
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1387 KB) |  | HTML iconHTML  

    Taiwan has been experiencing good economic growth in the last few decades and electronic industry contributes significantly to the export in recent years. The European and Japanese requirements on electronic products, electrical products and automobile production will put a lot of restrictions on the export items in these areas in the next few years to come. Taiwan government has recognized the need and understood that green products will be able to meet future requirements and compete for global market. Since three years ago, seminar, workshop and international conference have been held to promote green design in Taiwan, especially in the key industries. At the same time, technical publications were produced and relevant design tools were developed to help industries to go for green design or design for environment, design for recycling and so on. The Green Design Network, sponsored by the government, is developed as an information platform to provide information on tools, local and international activities, relevant regulations, design case studies, reference and web sites, promoting organizations and definitions, etc to facilitate the industries to perform green design. The launching of the network is a pilot in Asia and may be expanded in future to regional and international level. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Recent advances of interconnection technologies using anisotropic conductive films

    Publication Year: 2004 , Page(s): 229 - 234
    Cited by:  Papers (4)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1546 KB) |  | HTML iconHTML  

    Anisotropic conductive films(ACFs) consists of conducting particles and adhesive resins and have been widely used for packaging technologies in FPDs(Flat panel displays) such as LCDs(Liquid crystal displays) for last decades. So far various packaging technologies such as TCP(Tape carrier package) on LCD panel or PWB(Printed wiring board), COF(Chip on flex) on LCD panel or PWB and COG(Chip on Glass) using ACFs have been realized to meet the requirement of fine pitch capability and make the flat panel displays smaller, lighter and thinner. In order to meet the requirement of finer pitch interconnection of outer lead of TCP in LCD packaging technologies, the influence of conducting particles on contact resistance of ACF joints was investigated. It was found that the 50 micron pitch of outer lead interconnection of TCP is realized by optimizing the hardness of conducting particles. In addition, to meet fine pitch capability smaller than 50 micron pitch, the improvement of the adhesion characteristics against COF has been demonstrated in outer lead interconnection. It was confirmed that making conducting particles smaller is advantageous for the driver IC with small bump size and space in COG. Low temperature curable ACF using new curing system which cross-links at 140 degrees C in 10 sec bonding has been demonstrated in TCP/PWB interconnection. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Philips our experience in the introduction of leadfree soldering

    Publication Year: 2004 , Page(s): 18 - 25
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1525 KB)  

    First Page of the Article
    View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Effects of heating factors on the geometry size of unrestricted lead-free joints

    Publication Year: 2004 , Page(s): 81 - 85
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1555 KB) |  | HTML iconHTML  

    In this paper, the effects of heating factor on the geometry size of unrestricted lead-free joints were investigated. The morphologies of IMC formed in the joint were studied in detail by using SEM and EDX. When the Sn3.5Ag0.5Cu solder joint was formed in unrestricted condition, the width of the joint and the mean thickness of interfacial IMC increased with the increase of heating factor. The volume of the joint was larger than the volume of the Sn3.5Ag0.5Cu solder, but the effects of heating factor on the change of volume were undulate. The morphologies of the interfacial IMC were needle-like when heating factor was small, and then, grew, coarsened when heating factor increased. The tensile fractography of the joint indicated that the morphologies of IMC at fracture surface were various. Some of IMCs shaped like pyramid, and some of IMCs shaped like needle. And part of the fracture surface located in the solder, and part of the fracture surface located at the interface between the interfacial IMC and solder. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Manufacturability and reliability of lead-free package

    Publication Year: 2004 , Page(s): 105 - 109
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1478 KB) |  | HTML iconHTML  

    The European Community has been finalized to phase out on July 1,2006 for Lead(Pb) in electronic products. This cause the semiconductor industry is required to study new materials for replace the lead in its products. This paper presents the manufacturability and reliability study of the commercial lead-free alternatives to replace the currently used solder plating. This paper presents the findings of a series of experiment to evaluate various commercial lead-free plating alternatives, including tin and tin-bismuth products. The 2 different IC package types (Gull wing and J-Bend) were used in both off line and in a production environment to evaluate plating quality on solderability aspects including plating thickness, composition, ionic impurity, morphology grade, solderability (tested after a variety of thermal & humidity conditioning parameters), wettability and lead pull tests of surface mounted packages (using different reflow profiles - both NEMI and JEDEC recommended), and tin whisker growth. Since no lead-free plating standards of quality were available at the time of the study, normal solder plating standards were used as a reference. Tin and tin-bismuth plating were further investigated in production processes to attempt to eliminate the initial quality issues, and to develop, fine-tune and optimize the plating process, through a manufacturability study and reliability study. Tin plating looked the most promising material. Tin whisker growth is a major reliability problem when Pb-free deposits are implemented. This paper also presents some of the tin whisker mechanistic studies undertaken on one of the Pb-free chemistries tested. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Contact resistance and fretting corrosion of lead-free alloy coated electrical contacts

    Publication Year: 2004 , Page(s): 127 - 135
    Cited by:  Papers (2)
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1709 KB) |  | HTML iconHTML  

    As lead-free solders replace tin-lead solders in soldering, it is also expected that lead-free solder alloys will be used as contact finish materials for electrical contacts. In this study, the contact resistance and fretting corrosion of tin-silver-copper and tin-copper coatings were investigated and compared with tin-lead eutectic coating. The contact resistance before after different aging conditions, including mixed flowing gas, steam, and dry heat aging, was examined. Tin-silver-copper and tin-lead alloy coatings have similar performance on contact resistance versus contact normal force after dry heat aging and MFG aging. Severe degradation was found on tin-silver-copper coatings after steam aging. Higher contact force is suggested in the application of tin-silver-copper solder alloy coating than for eutectic tin-lead alloy coatings. Fretting corrosion on tin-silver-copper and tin-copper lead-free alloy coatings was studied and compared with tin-lead coating. Fretting corrosion experiments were conducted and compared at different temperatures and normal forces. In general, tin-silver-copper and tin-copper alloys show equal or better fretting corrosion resistance than tin-lead eutectic alloy at the experimental conditions in this study. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Integrating environmental product design into HP inkjet printing supplies

    Publication Year: 2004 , Page(s): 86 - 91
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1517 KB) |  | HTML iconHTML  

    At HP, we believe that environmentally sustainable development is not an option, but an imperative. HP works toward a sustainable future by developing programs that reduce our environmental footprint, as well as those of our customers and partners. Our vision is to develop products and solutions, and operate our company in such a way, that we are able to lead global businesses toward a sustainable future. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.
  • Formation of fine pitch solder bumps on polytetrafluoroethylene printed circuit board using dry film photoresist

    Publication Year: 2004 , Page(s): 117 - 122
    Save to Project icon | Request Permissions | Click to expandQuick Abstract | PDF file iconPDF (1529 KB) |  | HTML iconHTML  

    We demonstrated the applicability of dry film photoresists (DFR) in photolithography process for fine pitch bumping on the polytetrafluoroethylene (PTFE/Teflon®) printed circuit board (PCB). The copper lines were formed with 100μm width and 18μm thickness on the PTFE test board, and varying the gaps between two copper lines in a range of 100-200μm. The DFRs of 15μm thickness were laminated by hot roll laminator, by varying laminating temperature from 100°C to 150°C and laminating speed. We found the optimum process of DFR lamination on PTFE PCB and accomplished the formation of indium solder bumps. The optimum lamination condition was temperature of 150°C and speed of about 0.63cm/s. And the smallest size of indium solder bump was diameter of 50μm with pitch of 100μm. View full abstract»

    Full text access may be available. Click article title to sign in or learn about subscription options.