{"title":"Sn2.5Ag0.5Cu lead free solder balls with \"Ge\" and \"Ni\"","authors":"R. Lee, Wha Soo Sin, J. K. Jeon, Heui Seog Kim","doi":"10.1109/ISAPM.2005.1432060","DOIUrl":"https://doi.org/10.1109/ISAPM.2005.1432060","url":null,"abstract":"Recently, environmental-friendly products have significantly increased the development of lead free solder material. Some products are already in production and most of semiconductors will be released lead-freely. Among the various lead-free solders, the SnAgCu family of solders has been known as one of the leading candidates for high volume mass-production. However, SnAgCu still has a discoloration issue during ir-reflow and burn-in test, and the market requires stronger solder joint for fatigue bending and impact test due to the mobile electronics. In this paper, the countermeasure with adding \"Ge\" and \"Ni\" to prevent SnAgCu solder balls from discoloration is investigated and the optimization(3.0 /spl rarr/ 2.5%) of the weight ratio of \"Ag\" contents to enhance solder joint for fatigue bending and impact test is studied and reliability test for the optimized Sn2.5Ag0.5Cu composition is investigated.","PeriodicalId":181674,"journal":{"name":"Proceedings. International Symposium on Advanced Packaging Materials: Processes, Properties and Interfaces, 2005.","volume":"333 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"122848307","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Improvement of electrical performance of anisotropically conductive adhesives","authors":"Yi Li, K. Moon, C. Wong","doi":"10.1109/ISAPM.2005.1432079","DOIUrl":"https://doi.org/10.1109/ISAPM.2005.1432079","url":null,"abstract":"To improve the electrical properties of the anisotropically conductive adhesive (ACA) joints with the potential for fine pitch interconnect, self-assembled monolayer (SAM) compounds are introduced to treat nano silver (Ag) fillers. Thermogravimetric analyzer (TGA), differential scanning calorimeter (DSC), contact angle and photoacoustic Fourier transfer infrared (FTIR) results indicated the SAMs were well coated on the nano Ag particles. Furthermore, these SAM-treated ACAs were thermally stable at processing temperatures of the ACA samples. By introducing the novel SAM materials into the interfaces between nano metal fillers and the substrate bond pads, the conductivity and current carrying capability of ACAs were improved significantly due to the stronger bonding between nano fillers and SAM and consequently the improved interface properties of the high performance ACA. The improved electrical performance of nano Ag filled ACAs was accompanied with the higher thermal conductivity as well.","PeriodicalId":181674,"journal":{"name":"Proceedings. International Symposium on Advanced Packaging Materials: Processes, Properties and Interfaces, 2005.","volume":"13 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124055427","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"High frequency design and characterization of SU-8 based conductor backed coplanar waveguide transmission lines","authors":"Felix D. Mbairi, H. Hesselbom","doi":"10.1109/ISAPM.2005.1432083","DOIUrl":"https://doi.org/10.1109/ISAPM.2005.1432083","url":null,"abstract":"The epoxy-based negative photoresist SU8 is widely, used within the MEMS (microelectromechanical systems) community, and is well known for its ability to form thick layers with high aspect ratios and for its chemical resistance. However, only a few papers have investigated the electrical properties of this material and mostly within the MEMS area or at lower frequency ranges. This paper presents the design and characterization of conductor-backed coplanar waveguide (CBCPW) transmission lines using SU-8 dielectric material. The coplanar transmission lines are carefully designed using EDA tools, and fabricated on a metallized glass substrate coated with SU-8 material. S-parameter measurements are performed from 45 MHz to 50 GHz using a vector network analyzer and a probe station. From these measurements, transmission line parameters such as characteristic impedance, attenuation constant, effective dielectric constant, loss tangent, etc, are determined. The design procedure, fabrication process and measurement results are described in this paper. To our knowledge, this is the first time the SU-8 material is characterized in microelectronics using CBCPW transmission lines.","PeriodicalId":181674,"journal":{"name":"Proceedings. International Symposium on Advanced Packaging Materials: Processes, Properties and Interfaces, 2005.","volume":"25 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126354452","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Electromigration in eutectic tin-lead solder lines at the device temperature","authors":"R. Agarwal, K. Tu","doi":"10.1109/ISAPM.2005.1432069","DOIUrl":"https://doi.org/10.1109/ISAPM.2005.1432069","url":null,"abstract":"Electromigration in eutectic SnPb has been studied at the device temperature i.e. 100/spl deg/C and at three different current densities viz. 5/spl times/10/sup 3/ A/cm/sup 2/, 5/spl times/10/sup 4/ A/cm/sup 2/ and 5/spl times/10/sup 4/ A/cm/sup 2/. The test samples are prepared by reflowing solder into V-grooves etched on [001] Si wafer. The accumulation of a large lump of solder is observed at the anode for 5/spl times/10/sup 3/ A/cm/sup 2/ and 5/spl times/10/sup 4/ A/cm/sup 2/ current densities. The dominant diffusing species is found to be Pb in both cases. At 5/spl times/10/sup 3/ A/cm/sup 2/, the electromigration doesn't occur. The effects of current stressing on microstructure of eutectic SnPb solder have also been reported. Grain coarsening is observed, which becomes very significant with increasing current density.","PeriodicalId":181674,"journal":{"name":"Proceedings. International Symposium on Advanced Packaging Materials: Processes, Properties and Interfaces, 2005.","volume":"184 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131717939","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
Hongjin Jiang, K. Moon, Lingbo Zhu, Jiongxin Lu, C. Wong
{"title":"The role of self-assembled monolayer (SAM) on Ag nanoparticles for conductive nanocomposite","authors":"Hongjin Jiang, K. Moon, Lingbo Zhu, Jiongxin Lu, C. Wong","doi":"10.1109/ISAPM.2005.1432087","DOIUrl":"https://doi.org/10.1109/ISAPM.2005.1432087","url":null,"abstract":"To improve the electrical property of the isotropic conductive adhesives (ICA), self-assembled monolayer (SAM) compounds were used to help the dispersion of silver nanoparticles in epoxy resin. Silver nanoparticles were first treated by the SAM in order to increase the filler loading of nanoparticles in epoxy resin. The bonding and thermal debonding behavior between silver and SAM was investigated by differential scanning calorimeter (DSC). The amount of SAM coated on Ag nanoparticles was tested by thermogravimetric analysis (TGA). Scanning electron microscopy (SEM) was used to study the morphologies of SAM treated Ag nanoparticles before and after the heat treatment. Several kinds of epoxy formulation were prepared by using SAM-treated Ag nanoparticles as conductive fillers and the resistivities were studied.","PeriodicalId":181674,"journal":{"name":"Proceedings. International Symposium on Advanced Packaging Materials: Processes, Properties and Interfaces, 2005.","volume":"171 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"132310281","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Substrate effects on the creep properties of pure Sn solder joints","authors":"Kyu-Oh Lee, J. Morris, F. Hua","doi":"10.1109/ISAPM.2005.1432038","DOIUrl":"https://doi.org/10.1109/ISAPM.2005.1432038","url":null,"abstract":"This study investigated the influence of substrate metallization on the microstructure and creep behavior of the pure tin solder joints. Both symmetric (Cu:Cu) and the asymmetric (Cu:Au/Ni) metallizations were tested. The solder joints with asymmetric substrates had lower creep rates than those with symmetric (Cu:Cu) substrates. (Cu-Ni)/sup 6/Sn/sup 5/ intermetallics formed on all substrates. However, a dramatic and anomalous intermetallic growth was observed on the Ni-side of the asymmetric joints; after typical reflow the intermetallic reached almost one third of the solder joint thickness. It appears that the abnormally thick intermetallic inhibits creep in the asymmetric joint and is the primary cause of the lower creep rates.","PeriodicalId":181674,"journal":{"name":"Proceedings. International Symposium on Advanced Packaging Materials: Processes, Properties and Interfaces, 2005.","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127912786","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
F. Ren, J. Nah, J. Suh, K. Tu, B. Xiong, L.H. Xu, J. Pang
{"title":"Effect of electromigration on mechanical behavior of solder joints","authors":"F. Ren, J. Nah, J. Suh, K. Tu, B. Xiong, L.H. Xu, J. Pang","doi":"10.1109/ISAPM.2005.1432048","DOIUrl":"https://doi.org/10.1109/ISAPM.2005.1432048","url":null,"abstract":"The combination of electromigration effect and stress effect was investigated in lead free solder joints with a diameter of 300/spl mu/m. One dimensional structures, metal (wire)-solder (ball)-metal (wire) was developed. Mechanical force and current could be applied serially or simultaneously. The current density of electromigration was 1/spl sim/5/spl times/10/sup 3/ A/cm/sup 2/. The working temperature was 100-150/spl deg/C. Tensile test and shear test were taken before and after electromigration to make the comparison. The tensile strain rate was 3/spl mu/m/min. The experiment results show that, the samples broke at the middle of solder without applying current. However, after applying current of electromigration for 1 day, 2 days or longer, the failure always occurred at cathode interface. And the tensile strength was lower with longer electromigration time or higher current density. Shear test also illustrates the electromigration effect on mechanical property in composite solder joints.","PeriodicalId":181674,"journal":{"name":"Proceedings. International Symposium on Advanced Packaging Materials: Processes, Properties and Interfaces, 2005.","volume":"2014 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128016200","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"The metallic nickel inserted p/sup -//p/sup +/ Si substrate used for RF crosstalk reduction in mixed signal ICs","authors":"Xi Zhang, K. Chong, Yahong Xie, K. Tu","doi":"10.1109/ISAPM.2005.1432075","DOIUrl":"https://doi.org/10.1109/ISAPM.2005.1432075","url":null,"abstract":"A novel approach for 3-dimensional substrate impedance engineering of p/sup -//p/sup +/ Si substrate was studied for mixed-signal integrated circuit applications. For enhanced radio frequency (RF) crosstalk isolation, a highly conductive region analogous to a moat was inserted in the substrate between the noise producing and noise sensitive circuits to serve as grounded shields. Electroless plating was used to metallize the macroporous silicon moat etched beforehand within the p/sup -//p/sup +/ substrate to isolate electromagnetic interference and provide \"true ground\" contacts. The electroless plating was conducted in a concentrated aqueous solution containing Ni/sup 2+/ and NH/sup 4/F. Metallic Ni was rapidly deposited without using a reducing agent or any activation treatment at a slightly elevated temperature. After certain immersion duration, the initially single crystalline Si sidewall of the pores was completely modified by the polycrystalline metallic Ni while the original one-dimensional straight pore structure was still maintained. Thus a highly conductive porous structure was obtained in the substrate and RF crosstalk was reduced to the level limited by that across the air gap between the measurement probes. This technique offers further improvement with regard to RF crosstalk via substrate on the isolation effect achieved by high impedance through-the-wafer porous Si.","PeriodicalId":181674,"journal":{"name":"Proceedings. International Symposium on Advanced Packaging Materials: Processes, Properties and Interfaces, 2005.","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114174855","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
{"title":"Electromigration study on Cu-Sn interconnections","authors":"Taeyeop Lee, F. Hua, J. Morris","doi":"10.1109/ISAPM.2005.1432046","DOIUrl":"https://doi.org/10.1109/ISAPM.2005.1432046","url":null,"abstract":"This research concerns the influence of electron current on the diffusion of Sn and Cu in simple Cu-Sn and Cu-Sn-Cu diffusion couples. The diffusion couples are designed to permit in situ studies of the progress of diffusion. Initial tests were done in 60/spl deg/C air with a current density of 1 /spl times/ 10/sup 4/A/cm/sup 2/. The results showed Cu movement into Sn in the direction of the electron current. With accompanying grain boundary sliding of the Sn grains. There is also evidence for Sn flow in the direction opposite the electron current.","PeriodicalId":181674,"journal":{"name":"Proceedings. International Symposium on Advanced Packaging Materials: Processes, Properties and Interfaces, 2005.","volume":"3 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125137921","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}
H. Zhong, S. Rubinsztajn, A. Gowda, D. Esler, D. Gibson, D. Buckley, J. Osaheni, S. Tonapi
{"title":"Utilization of carbon fibers in thermal management of microelectronics","authors":"H. Zhong, S. Rubinsztajn, A. Gowda, D. Esler, D. Gibson, D. Buckley, J. Osaheni, S. Tonapi","doi":"10.1109/ISAPM.2005.1432086","DOIUrl":"https://doi.org/10.1109/ISAPM.2005.1432086","url":null,"abstract":"Power dissipation is expected to increase exponentially to 150-250 W per chip over the next decade. To manage this large heat output, it is necessary to minimize the thermal resistance between the chip and a heat dissipation unit that the device is attached to. It is therefore important to further improve the thermal performance of thermal interface materials (TIMs), which can be achieved through 1) improvement of the bulk thermal conductivity of TIMs; and/or 2) reduction of interfacial thermal resistances between the TIM and the device and/or TIM and the heat dissipation unit. The latter improvement may be obtained by enhanced physical properties of TIMs (e.g., viscosity or wetting ability) and/or surface modification of the heat dissipation unit or the inactive side of the device. Researchers have tried to take advantage of the high 1D thermal conductivities of graphite fibers, and more recently of carbon nanotubes (CNT), to reduce the thermal resistance between the chip and the heat dissipation unit. The efforts can be classified into three categories: 1) Forming pre-aligned graphite fiber or CNT films that have high bulk thermal conductivities in the heat transport direction, and applying such films as TIMs; 2) incorporating randomly oriented graphite fibers or CNT into silicone or epoxy matrices in the presence or absence of a second filler to improve bulk thermal conductivities, and applying the thus-formed blend as thermal greases, or adhesives or gels; and 3) growing CNT or graphite fibers from the heat sink/spreader surface and/or silicon backside and assembling them together with a TIM a to increase the bulk heat transport property and reduce the interfacial resistances, In this paper, we will present results for each of the three approaches, and discuss the challenges facing each one.","PeriodicalId":181674,"journal":{"name":"Proceedings. International Symposium on Advanced Packaging Materials: Processes, Properties and Interfaces, 2005.","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2005-03-16","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"130592880","PeriodicalName":null,"FirstCategoryId":null,"ListUrlMain":null,"RegionNum":0,"RegionCategory":"","ArticlePicture":[],"TitleCN":null,"AbstractTextCN":null,"PMCID":"","EPubDate":null,"PubModel":null,"JCR":null,"JCRName":null,"Score":null,"Total":0}