2007 8th International Conference on Electronic Packaging Technology最新文献

{"title":"The Application of a Type of Electric Pastern in the Bonding Technique of the Microcircuit Board","authors":"Zhiping Zhao, L. Cao","doi":"10.1109/ICEPT.2007.4441463","DOIUrl":"https://doi.org/10.1109/ICEPT.2007.4441463","url":null,"abstract":"The authors have performed experiments in the felting of electric pasterns upon the samples of aluminum alloy boards, gold-plating boards and glass strips, the method of which is to first felt 2 microcircuit boards with electric pastern and fix them with some mechanical devices, then keep them in the drying blast oven for 4 hours with a constant temperature of 150plusmn2degC and finally, cool them naturally to the ambient temperature. The series of experiments made include the testing of the extension and cutting intensity of the electric pastern, the testing of the volume resistivity of the electric pastern and the experiment of the concussion given to the electric pastern at relatively high or low temperatures, the purpose of which is to test the reliability of its felting quality and further to study the application of the electric pastern in the bonding technique of the microcircuit board. Obtained from the testing of extension intensity carried out with the relevant testing machine according to GB7124- 86, the testing value of aluminum alloy board is between 5.5M Pa and 6.99 M pa, the testing value of the gold-plating board is from 2.45M Pa to 3.07M Pa, which clearly mean that the joining intensity of electric pastern to aluminum alloy board is better than that to the gold-plating board. However, both intensities have met our demands and are acceptable. We also have tested the volume resistivity of the glass strips connected to it. Since for the bonding technique of the microcircuit board, it is usually acceptable if the resistivity of the electric pastern is less than 9.0 X10\"4 Q.cm, our testing data have shown that the quality of this type of electric pastern is satisfactory. Having fulfilled the concussion test for the microcircuit board at relatively high or low temperatures, we have tested the reliability of the bonding points. The finding shows that the change of the resistivity of the microcircuit board is within very small scale, and if assigned to every felting point, the change can simply be ignored, thus cannot affect the felting quality at all. To sum up, the series of experiments have given the proof that this type of electric pastern meets the requirements of the bonding technique of the microcircuit board connected by gold threads or gold bands.","PeriodicalId":325619,"journal":{"name":"2007 8th International Conference on Electronic Packaging Technology","volume":"18 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129713970","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":"Oxidation Behavior and Intermetallic Compounds Growth of Sn-Ag-Bi-Cr Lead-free Solder","authors":"Huang Wang, A. Hu, Cheng Li, D. Mao","doi":"10.1109/ICEPT.2007.4441468","DOIUrl":"https://doi.org/10.1109/ICEPT.2007.4441468","url":null,"abstract":"Concentrations of 0.1. 0.3. and 0.5 wt.% of Cr were added to Sn-3Ag-3Bi alloy to produce Sn-Ag-Bi-Cr alloys. The microstmcture is refined with Cr additions, while significantly improves the oxidation resistance. There is no change in the wettability and liquidus temperature after Cr additions. In addition, the effect of Cr addition on the intermetallic compounds was discussed.","PeriodicalId":325619,"journal":{"name":"2007 8th International Conference on Electronic Packaging Technology","volume":"19 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129788936","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":"Sagging Phenomenon of Micro-Solder Joints Fabricated by Laser Reflow Process","authors":"Wei Liu, Chunqing Wang, Yanhong Tian, Lingchao Kong","doi":"10.1109/ICEPT.2007.4441450","DOIUrl":"https://doi.org/10.1109/ICEPT.2007.4441450","url":null,"abstract":"Au surface finish is very common used as a protection layer on pad. In the traditional reflow process, Au is dissolved into solder, and AuSn4 intermetallic components (IMCs) forms. However, for the solder joints fabricated by laser soldering, the morphology and distribution of the AuSnx IMC are quite different from that in solder joints fabricated by traditional reflow methods. This paper reports a 'sagging phenomenon' that has been observed from a study in the right-angled solder interconnections fabricated by laser reflow process. The solder was Sn-3.5Ag-0.7Cu and Sn-2.0Ag-0.75Cu-3Bi alloys (120 mum in diameter). On the laser reflowed solder joint, sink steps were found near the interface of solder and the edge of pad, which was made up of Cu plated with 3 mum thickness of Au, and this phenomenon was called as sagging. However, no sagging phenomenon was observed at the interface of solder and the edge of another pad finished with 0.01 mumTa/0.1 mumNi/4.0 mumAu, the material beneath the pad was thick Al2O3. In addition, Sn-Pb eutectic solder was also introduced in this study as a comparison, the sagging phenomenon in Sn-Pb eutectic solder joint was not as seriously as that in the two kinds of lead-free solder. The study results indicate that sagging phenomenon happened after the laser reflow process is related to the following factors: different cooling speed at the interfaces of solder and the pads, the Melting temperature difference between solder and IMCs, shrinkage of solder when it solidifies, and wetting performance of solder on solidified IMCs.","PeriodicalId":325619,"journal":{"name":"2007 8th International Conference on Electronic Packaging Technology","volume":"65 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"124589008","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":"University Education Curriculum and Lab Construction On Microelectronics Packaging and Assembly","authors":"Xiaosong Ma, Daoguo Yang, G.Q. Zhang","doi":"10.1109/ICEPT.2007.4441572","DOIUrl":"https://doi.org/10.1109/ICEPT.2007.4441572","url":null,"abstract":"China's electronics industry has seen a significant development in the last decades. The electronics manufacturing industry has become the country's largest industry. Many well-qualified researchers and engineers are needed to meet the demands of the microelectronics industry and research. The fast developing electronics industry challenges the conventional university education. How to innovate the education curriculum to provide qualified engineers for the electronics industry is a challenging task for universities. Education program on microelectronic packaging and assembly has been established at GUET. In this paper, the experiences of establishing the multi-level education program for the microelectronics manufacturing are briefly summarized. A focus is put on the new bachelor's degree program of Microelectronic Manufacturing Engineering. The objective, scope and curriculum structure of the education program are proposed, which is with an emphasis on the sectors of electronic packaging, assembly and test. This proposal is supported by the fact of the existing huge demands for the qualified engineers in these sectors. To achieve the goal, the core courses for the educational curriculum and educational means are proposed and discussed. Further effort to enhance the educational ability is needed.","PeriodicalId":325619,"journal":{"name":"2007 8th International Conference on Electronic Packaging Technology","volume":"57 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123468261","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":"Effect of Under Bump Metallization (UBM) Quality on Long Term Reliability","authors":"R. Rao, M. Seabock, T. Fang, R. Carew","doi":"10.1109/ICEPT.2007.4441571","DOIUrl":"https://doi.org/10.1109/ICEPT.2007.4441571","url":null,"abstract":"Ti/Cu/Ni Under Bump Metallization (UBM) structure is used for eutectic. i.e.. 63Sn37Pb. solder bump with Ti for adhesion and seal. Cu as current earning layer, and electroplated Ni as diffusion barrier. In this study, the effect of the integrity of UBM structure within a passivation via, particularly the integrity of Ni barrier layer, on the product long-term reliability has been investigated. The defective Ni plating within a passivation via is mainly due to the bumping pattern, the difficulty in monitoring Ni thickness and a non-appropriate Ni thickness specification. The reliability testing results indicate that the defective Ni plating has no effect on bump shear strength, temperature cycling and high temperature storage tests. But. it does cause a failure when an elevated temperature and current are applied such as temperature humidity with Bias Current test in tins study. Failure analysis was performed to understand the failure modes and failure mechanisms were also analyzed. The analysis results indicate that the Ni thickness, particularly at the corner of via is most critical to the reliability. In order to guarantee the long-term reliability, it is recommended that an appropriate Ni thickness specification be established based on quantitative analysis results by considering six major factors discussed in section eight.","PeriodicalId":325619,"journal":{"name":"2007 8th International Conference on Electronic Packaging Technology","volume":"26 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128094056","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":"Mixed Mode Fracture Toughness Test of Bimaterial Interface in Different Humidity Conditions","authors":"Anlin Ye, L. Qin","doi":"10.1109/ICEPT.2007.4441531","DOIUrl":"https://doi.org/10.1109/ICEPT.2007.4441531","url":null,"abstract":"The strength of an interface is subjected to temperature, humidity and different global mixed mode loading conditions. This paper describes the measurement of the interface fracture toughness as a function of relative humidity using a compact mixed mode (CMM) specimen in Instron 5567 testing system machine. In the test, The conditions of specimen are parting dry condition and moisture preconditioning (85degC /85% RH/168h and 85degC /60 %RH/168h), measuring fracture critical value of specimen with different global mixed mode loading conditions, the fracture critical value of specimen is the average failure value of 2 specimens at each loading angle of global mixed mode, the fracture critical value shows that the interface fracture toughness is decreased when relative humidity increased. Then, finite element analysis modeling for an interface crack in the CMM specimen provides the necessary stress intensity factor calculation. The results show that the mode II fracture toughness generally display a larger value than the mode I toughness in the same humidity condition. Moreover, fracture toughness is decreased when humidity increased at the same mixed mode loading. The Failure criterion based on a failure analysis diagram or effective critical stress intensity factors are proposed for interface cracks loaded under different mixed-mode and humidity fracture conditions. This method of the test for data and the finite element simulation for evaluation of interfacial fracture toughness.","PeriodicalId":325619,"journal":{"name":"2007 8th International Conference on Electronic Packaging Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"129995759","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":"Effect of Post-Mold Curing of Epoxy Molding Compound on Wirebond Reliability in a MOSFET","authors":"R.T. Nayak, T. Ahmed, A. Krishna, K. Hollis","doi":"10.1109/ICEPT.2007.4441432","DOIUrl":"https://doi.org/10.1109/ICEPT.2007.4441432","url":null,"abstract":"Automotive microelectronic packages experience severe thermal stresses that occasionally cause components and electrical interconnection damage. In tins field of application high reliability is of decisive importance, especially for aluminum wire bonds with diameters of the order of 125 mum, connecting the silicon device with the output pins. Silica filled epoxy resins as encapsulation in chip packages play a major influence on reliability and functionality of microelectronic devices. The paper intends to help understand the reliability of Aluminum wirebonds inside a leaded electronic package like Power MOSFET (metal oxide silicon field effect transistor) under the influence of post-mold curing (PMC) on thermo-mechanical properties of the mold material, like glass transition temperature (Tg), coefficients of thermal expansion (CTE) and flexural moduli. Experimental validation indicates an electrical open gate in the specimen caused due to delamination of gate bond wire (SAT and SEM images) near the leadframe bonding post under power thermal cycling from -40C to 125C. Finite element modeling is used to simulate the stresses the package goes through during reliability tests. The FE model consists of the entire MOSFET package including the lead frame, over mold, chip, substrate. Al wire loops and corresponding bond pads. The simulation considering thermal mismatch predicts high in-plane shear forces at the heel of the wire bond supported by the empirical test results. Optimum values of thermo-mechanical properties having a combination of low CTE and high E value at a higher Tg (obtained by increased PMC duration), recommended to ensure reliability of wire bond. Further, results show evidence of higher variation of in-plane shear force on the wire bond with change in CTE as compared to E. Results derived from numerical simulation and experimental data is used to serve as a guideline in the selection of suitable molding compound.","PeriodicalId":325619,"journal":{"name":"2007 8th International Conference on Electronic Packaging Technology","volume":"45 6 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134371571","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 Determinations of Pb, Cd, Hg, Cr6+, PBBs/PBDEs to Comply with RoHS Directive","authors":"L. Hua, Y.P. Wu, B. An, Y. Chan, B.Y. Wu, F.S. Wu","doi":"10.1109/ICEPT.2007.4441478","DOIUrl":"https://doi.org/10.1109/ICEPT.2007.4441478","url":null,"abstract":"For RoHS compliance, a method coupled inductively coupled plasma-optical emission spectrometry (ICP-OES), gas chromatography-mass spectrometry (GC-MS), and UV-visible spectrophotometry with microwave technology was developed to determine trace Cd, Hg, Pb, Cr6+, PBBs/PBDEs in electronic and electrical products (EEP). Elements were screened by Energy dispersion X-ray fluorescence spectrometry (EDXRF). In order to achieve good performance, other methods such as colorific test, inter-element correction (IEC) and standard addition techniques etc. were performed. By this study, it showed that analyses of Hg, Cd, Pb by ICP-OES and Cr6+ by UV-visible spectrophotometry had a RSD <5%, and a RSD <1% for PBBs/PBDEs by GC-MS analyzer. UV-visible spectrophotometry offered a good alternative for Cr6+ determination with alkali digestion, the inferences from Fe3+, Pb2+ etc. were eliminated by K2HPO4 buffer. The ramifications from monoBB/BDE to DecaBB/BDE were distinctly separated and successfully determined in the optimized condition. Furthermore, microwave system did an excellent job of consistently putting solid samples into solutions and had a moderate compatibility with spectrometric analyzer due to good recoveries. Though RSD of XRF screening was larger than 10%, it proved to be an easier, cheaper, faster technique. Because of the combination of multiple methodologies, the restricted substances can be determined with good precision and high reliability. It provides a prominent project for EE industries to comply with RoHS compliance.","PeriodicalId":325619,"journal":{"name":"2007 8th International Conference on Electronic Packaging Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131020353","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":"Properties and Reliability of Sn-Pb and Lead-free Mixed Soldering","authors":"Huang Wang, A. Hu, Lihong Wang, P. Zhu, Chengkang Chang, Ming Li","doi":"10.1109/ICEPT.2007.4441544","DOIUrl":"https://doi.org/10.1109/ICEPT.2007.4441544","url":null,"abstract":"During the transition from Sn-Pb solder to lead-free solder, it is inevitable to encounter the reliability difficulties when lead-free and Sn-Pb materials were used within the same mounting process. To solve the problem in the mixed soldering, two methods were adopted that is improving the soldering temperature and electroplating Sn-Pb on the surface of the devices then soldering in a lower temperature. Mechanical strength of the solder joint, fracture morphology and the intermetallic compound (IMC) at the interface between solder and board materials were investigated. The experimental results showed the inclination of pores evolving when improving the solder temperature reduces the reliability. However, symmetrical solder joint with high reliability was obtained in the second method.","PeriodicalId":325619,"journal":{"name":"2007 8th International Conference on Electronic Packaging Technology","volume":"1246 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"133442796","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":"Effect of Solder Volume on Shear Strength between Sn-3.0Ag-0.5Cu Solder and Cu Metallization","authors":"Yang Shihua, Lin Pengrong, Tian Yanhong, Wang Chunqing, Liang Le, W. Qian","doi":"10.1109/ICEPT.2007.4441532","DOIUrl":"https://doi.org/10.1109/ICEPT.2007.4441532","url":null,"abstract":"Shear behavior of Sn-3.0Ag-0.5Cu solder joints on ball grid array substrates was investigated with different solder volumes and shear speeds to study the solder volume effect on shear properties. Both solder volume and shear speed were found to have strong effect on the shear strength. The shear force decreases obviously with the decrease of the solder volume due to the significant decrease of loaded area, while the shear strength has reverse trend. The shear strength increases sharply with the decrease of solder volume as a result of the discrepancy of interfacial reaction and microstructure. And the shear strength increases rapidly with the increase in shear speed due to the limited grain boundaries or interphase boundaries sliding and dislocation movement. After the shear test, fracture surfaces were investigated by canning electron microscopy equipped with energy dispersed x ray and it was found that the fracture mode of as-reflowed solder joints was primary ball cut within the bulk solder near the interface with a ductile rupture. The results suggest that even if the solder shear tests showed the same fracture mechanism, solder volume still has great effect on the shear properties at different shear speeds.","PeriodicalId":325619,"journal":{"name":"2007 8th International Conference on Electronic Packaging Technology","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2007-08-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"127411542","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}