2012 IEEE 62nd Electronic Components and Technology Conference最新文献

{"title":"All-wet Cu-filled TSV process using electroless Co-alloy barrier and Cu seed","authors":"F. Inoue, T. Shimizu, H. Miyake, R. Arima, S. Shingubara","doi":"10.1109/ECTC.2012.6248926","DOIUrl":"https://doi.org/10.1109/ECTC.2012.6248926","url":null,"abstract":"We demonstrated fabrication of Cu-TSV using all-wet process, which has a high potential to apply for the via-last Cu-TSV process. A Co-W alloy diffusion barrier layer was formed on SiO2 layer by electroless plating at 60 °C with Pd nanoparticle catalyst. The barrier layer was thin and continuous throughout a 2 φ × 24 μm TSV and its adhesion strength on SiO2 was as high as that of PVD-Ta. The Co-W alloy layer has undergone an interdiffusion test, which showed a high resistance against Cu diffusion into SiO2 layer. Then, seed layer was formed by electroless Cu deposition on the Co-W alloy layer through displacement reaction. These results reveal a feasibility of all-wet fabrication in a high aspect ratio TSV process.","PeriodicalId":6384,"journal":{"name":"2012 IEEE 62nd Electronic Components and Technology Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"72598226","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":"Investigation of phosphorus impact on lead-free BGA solder joint and failure mechanism","authors":"Ming Sun, Muh-ren Lin, T. Chaudhry, R. Lutze","doi":"10.1109/ECTC.2012.6248873","DOIUrl":"https://doi.org/10.1109/ECTC.2012.6248873","url":null,"abstract":"Small amounts of phosphorus (P) are often added to lead-free solder balls in ball grid array (BGA) packages to act as an antioxidant during the packaging reflow process. This paper shows that the addition of phosphorus to lead-free solder results in early solder joint failure. Also, we developed the failure mechanism for this phenomenon, which has not previously been understood. Our study shows that the accumulation of phosphorus in the intermetallic compound (IMC) area during the reflow process results in the formation of a thin porous layer at the interface of the IMC layer and the Ni layer of the BGA ball pad. This thin porous layer adversely affects the bond strength of each solder joint. The failure mechanism was developed in terms of factors such as diffusion, deformation-induced stress, crystal structure, thermal stress, and testing environments. Such factors provide an insight into package reliability with regard to the components used in the package and in-service operating conditions (temperature, time, mechanical structure).","PeriodicalId":6384,"journal":{"name":"2012 IEEE 62nd Electronic Components and Technology Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"73432018","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 measurements in thin-film IPD and eWLB interconnections","authors":"R. Frye, Kai Liu, KyawOo Aung, M. P. Chelvam","doi":"10.1109/ECTC.2012.6249004","DOIUrl":"https://doi.org/10.1109/ECTC.2012.6249004","url":null,"abstract":"In this paper we describe measurements of electromigration failure times in the metal traces of silicon Integrated Passive Devices (IPDs) and in the redistribution layers of embedded Wafer-Level BGA (eWLB) structures, for both aluminum and copper traces, and for via connections between the two metal layers. The results of the test are used to determine the coefficients of Black's Equation, which is then used to find the extrapolated lifetimes. Maximum current density design guidelines are derived from these results to ensure device reliability in worst-case operation. Some minor differences are observed between these results and similar results for interconnections in conventional ICs. These differences probably arise from the larger conductor cross section and the softer organic dielectrics in IPDs and eWLB packages.","PeriodicalId":6384,"journal":{"name":"2012 IEEE 62nd Electronic Components and Technology Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84288255","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":"Cost-effective low-loss flexible optical engine with microlens-imprinted film for high-speed on-board optical interconnection","authors":"T. Shiraishi, T. Yagisawa, T. Ikeuchi, S. Ide, K. Tanaka","doi":"10.1109/ECTC.2012.6249035","DOIUrl":"https://doi.org/10.1109/ECTC.2012.6249035","url":null,"abstract":"There is a strong demand for optical interconnection technology to overcome bandwidth bottlenecks in high-end server systems. The interconnection speed in present systems is approaching 10 Gb/s, and higher-speed interconnections over 25 Gb/s are being discussed. To achieve such optical interconnections in commercial production, it is necessary to develop lower-cost and higher-speed optical transceiver modules. We propose a flexible printed circuit optical engine (FPC-OE) with a microlens-imprinted film and a polymer waveguide to achieve low-cost and high-speed operation. The microlens-imprinted film can be produced at low cost by using nanoimprint technology and can drastically reduce the optical loss of the FPC-OE with polymer waveguide. We successfully demonstrated error-free operation at 25 Gb/s with the fabricated optical transceiver that contains an FPC-OE, microlens-imprinted film, and a polymer waveguide.","PeriodicalId":6384,"journal":{"name":"2012 IEEE 62nd Electronic Components and Technology Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84448207","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":"Preferred orientation of 30 μm fine pitch Sn2.5Ag micro-bumps studied by synchrotron polychromatic x-ray Laue microdiffraction","authors":"T. Tian, Kai Chen, Martin Kunz, Nobumichi Tamura, C. Zhan, Tao-Chih Chang, K. Tu","doi":"10.1109/ECTC.2012.6248938","DOIUrl":"https://doi.org/10.1109/ECTC.2012.6248938","url":null,"abstract":"Synchrotron radiation white beam x-ray microdiffraction was employed to study grain size and orientation of fine pitch Sn2.5Ag micro-bumps. The indexing of the Laue patterns shows that there is mostly one dominant grain orientation in each micro-bump. Moreover, a statistics study based on the characterization of 72 micro-bumps, shows that the [001] direction, which is the fast diffusion path for Ni/Cu atoms in Sn tends to be parallel to the substrate of the test vehicle. This property remains stable after repeated reflow processes.","PeriodicalId":6384,"journal":{"name":"2012 IEEE 62nd Electronic Components and Technology Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84725656","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":"Development of micro-alloying method for Cu pillar solder bump by solid liquid interaction","authors":"Wen Yin, Daquan Yu, Fengwei Dai, Chongshen Song, Zhang Bo, L. Wan, Han Yu, J. Sun","doi":"10.1109/ECTC.2012.6249068","DOIUrl":"https://doi.org/10.1109/ECTC.2012.6249068","url":null,"abstract":"Fine pitch micro bump is one of the key technology for 3D packaging since it can greatly improve the interconnect density. In this paper, we describe a new micro-alloy method for joining Cu pillars by forming solder bump alloys. The alloy composition is controlled by thin metal layer deposition and subsequent solid-liquid interactions. Four elements, e. g., Ag, Cu, Ni and Cr, were selected for micro-alloying Cu/Sn bumps and compositions of Sn-(1~2)Ag, Sn-2Ag-0.5Cu, Sn-(0.03~0.07)Ni, and Sn-(0.03~0.07)Cr were formed on Cu pillars. The microstructure of the solder bumps was studied before and after temperature cycling. The alloying process, and the effect of alloying on the interfacial microstructure and the growth of the intermetallic compounds (IMC) were investigated. The results suggest that the dissolution rate of additional metal in the molten Sn is sufficiently rapid to form solder bumps of varying compositions during a single reflow step. With Ag alloying, Ag3Sn crystals formed and were finely dispersed in the solder. With trace Ni doping, Ni was dissolved into the solder and the IMC layer thickness increases since the Cu solubility in molten Sn increases in the presence of Ni. In comparison, it is quite interesting that with trace Cr alloying, Cr2Sn3 crystals were detected in the solder and that a thinner IMC layer resulted in comparison to Ni-alloying solder and pure Sn on Cu pillars. The susceptibility to whisker growth during alloying was also investigated. No Sn whisker formation or growth was observed on the solder bumps after 1000 thermal cycles. The thickness of IMC layer became thicker after temperature cycling. In decreasing order, the thickness of the IMC layer on the Cu pillar was observed to be: Sn-0.07Ni>;Sn-2Ag>;Sn-0.07Cr>;Sn-2Ag-0.5Cu.","PeriodicalId":6384,"journal":{"name":"2012 IEEE 62nd Electronic Components and Technology Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85194022","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":"Single/few-layer boron nitride-based nanocomposites for high thermal conductivity underfills","authors":"Ziyin Lin, Yagang Yao, A. McNamara, K. Moon, C. Wong","doi":"10.1109/ECTC.2012.6249025","DOIUrl":"https://doi.org/10.1109/ECTC.2012.6249025","url":null,"abstract":"Thermal management in 3D packaging plays an important role in the device performance and reliability. The development of thermally conductive underfills is highly crucial, but still challenging. In this work, single/few-layer boron nitride (BN) was exfoliated from bulk h-BN flakes and was incorporated into epoxy resin via a solvent transfer method. [1] The structure of exfoliated BN was characterized by varieties of techniques, including scanning electron microscopy, transmission electron microscopy, electron diffraction, Raman microscopy, and UV-vis microscopy. The single/few layer boron nitride/epoxy composite was characterized by thermomechanical analysis and thermogravimetric analysis. The thermal conductivity of exfoliated BN was measured by an infrared thermal imaging method. A significant enhancement of thermal conductivity (220%) is observed at a low filler loading of 5 wt%, indicating that the single/few-layer BN is a promising filler for the development of novel underfill for 3D packaging.","PeriodicalId":6384,"journal":{"name":"2012 IEEE 62nd Electronic Components and Technology Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"85335659","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":"Metal-coated mono-sized polymer core particles for fine pitch flip-chip interconnects","authors":"M. Sugden, Changqing Liu, D. Hutt, D. Whalley, H. Kristiansen","doi":"10.1109/ECTC.2012.6248831","DOIUrl":"https://doi.org/10.1109/ECTC.2012.6248831","url":null,"abstract":"The increasing demand for fine pitch flip-chip interconnection has led to significant interest in alternatives to the widely used solder joints. The use of mono-sized metal coated polymer based micro-spheres is emerging as a method to achieve more robust and reliable interconnects for ball grid arrays and chip scale packages. This paper presents results from a collaborative research project investigating whether polymer cored interconnects are a viable replacement for such ultra-fine pitch solder joints. The focus of this work centres on the selective deposition of these polymer microspheres onto fine pitch bond pads. An important advantage of using such microspheres is that their mechanical properties can be tailored to suit the needs of the application, in addition to the relatively low usage of metals. Initial trials have been carried out using 9.8 μm diameter polymer particles which have been coated with electroless nickel and then an immersion gold surface layer. In order to selectively deposit these particles on to the bond pads of an ASIC device they were required to be charged. The particles were immersed in an aqueous acid solution and after rinsing in deionised water they were then transferred to a suitable solvent. This process resulted in a net positive charge on the particle surface which allowed the particles to be deposited using electrophoretic techniques i.e. an electric field was applied to the particle suspension to drive the particles to deposit on the substrate. The effect of this immersion in the aqueous acid solution on the surface metal layer of the particles has been studied using electron microscopy. The rate of electrophoretic deposition of the particles onto a homogeneous gold coated silicon substrate was studied to determine how the length of chemical treatment affects the particle deposition. Following from this the same technique was then used to deposit the particles directly on to the bond pads of an ASIC device. Using the ASIC as the cathode in the electrophoretic setup the particles were able to be selectively deposited onto bond pads with a pitch of 170 μm.","PeriodicalId":6384,"journal":{"name":"2012 IEEE 62nd Electronic Components and Technology Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"82212146","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":"Flexible system for real-time plasma decapsulation of copper wire bonded IC packages","authors":"J. Tang, J. Schelen, C. Beenakker","doi":"10.1109/ECTC.2012.6249076","DOIUrl":"https://doi.org/10.1109/ECTC.2012.6249076","url":null,"abstract":"Improvements of the Microwave Induced Plasma system especially designed for decapsulation of copper wire bonded integrated circuit (IC) packages are described. The system integrates a programmable XYZ-stage and a Charge-Coupled Device (CCD) camera allowing computer controlled process and real-time imaging on the details of the IC package during plasma etching. Parameters that affect the etching profile are investigated. Decapsulation of a plastic small outline package SO32 with 38 um copper wire bonds is conducted by three consecutive etching cycles using plasma beam scanning. The scan route and speed in relation to the plasma recipe and the package structure are discussed in detail. Causes of potential damage on the die and the wire bonds due to plasma etching are explained. Measures to improve the etching uniformity and to avoid potential overetching and oxidization damage are addressed.","PeriodicalId":6384,"journal":{"name":"2012 IEEE 62nd Electronic Components and Technology Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"84135447","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 measurements of TSV failures","authors":"Joohee Kim, D. Jung, Jonghyun Cho, J. Pak, J. Yook, J. C. Kim, Joungho Kim","doi":"10.1109/ECTC.2012.6248845","DOIUrl":"https://doi.org/10.1109/ECTC.2012.6248845","url":null,"abstract":"Due to a lot of thermal and mechanical loads during TSV process or post TSV process such as metallization and die stacking, disconnection failure can occur which results in 3D IC yield loss. Thus, a non-destructive diagnostic method by using one point probing for TSV failures is proposed to detect and differentiate TSV failure types and locations. With the fabricated test vehicles with disconnection failures, high-frequency measurements are conducted to verify the proposed diagnostic method, and full and partial disconnection failure is analyzed based on the high-frequency measurement results.","PeriodicalId":6384,"journal":{"name":"2012 IEEE 62nd Electronic Components and Technology Conference","volume":null,"pages":null},"PeriodicalIF":0.0,"publicationDate":"2012-07-30","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"83768464","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}