Please wait, while we are loading the content...
Please wait, while we are loading the content...
| Content Provider | The American Society of Mechanical Engineers (ASME) Digital Collection |
|---|---|
| Author | Nakoshi, Yutaro Miura, Hideo |
| Copyright Year | 2018 |
| Abstract | Electroplated gold thin films have been used for micro bumps in flip chip packing structures. However, it has been reported that physical properties and micro texture of the electroplated thin films vary drastically comparing with those of conventional bulk material, depending on their electroplating process. In addition, since one bump is going to consist of a few grains or a single grain due to the miniaturization of the 3D structures, it shows strong anisotropic mechanical properties because a face-centered cubic crystal essentially has strong anisotropy of physical properties. Therefore, there should be the wide distribution of characteristics of the micro bumps depending on their micro structure and the variation of the crystallinity of grains and grain boundaries enlarges the width of the distributions of various properties. Particularly, it was found that the long-term reliability of micro bumps and interconnections is degraded drastically by porous grain boundaries with a lot of defects because of the acceleration of atomic diffusion along the porous grain boundaries under the application of high current density (electromigration) and high mechanical stress (stress-induced migration). In this study, the effect of crystallinity, in other words, the order of atom arrangement of grain boundaries in electroplated gold thin films on the EM resistance was investigated experimentally. The crystallinity of the gold thin films was varied drastically by changing the under-layer material used for electroplating; such as Cr (30 nm) / Pt (50 nm)/ Au (200 nm) and Ti (50 nm) / Au (100 nm). The mechanical properties of the electroplated gold thin films were measured by using a nano-indentation test. Also, the micro textures such as crystallinity and crystallographic orientation of gold thin films were investigated by EBSD (Electron Back-Scatter Diffraction) and XRD (X-Ray Diffraction). It was clarified that the crystallinity of the electroplated gold thin films changed drastically depending on the crystallinity of the under-layer materials and heat treatment conditions after electroplating. This variation of the crystallinity should have caused the wide variation of mechanical properties of the electroplated gold films. Therefore, it is very important to control the crystallinity of the under layer used for electroplating in order to control the mechanical properties and reliability of the electroplated gold thin films. |
| File Format | |
| ISBN | 9780791852170 |
| DOI | 10.1115/IMECE2018-87278 |
| Volume Number | Volume 12: Materials: Genetics to Structures |
| Conference Proceedings | ASME 2018 International Mechanical Engineering Congress and Exposition |
| Language | English |
| Publisher Date | 2018-11-09 |
| Publisher Place | Pittsburgh, Pennsylvania, USA |
| Access Restriction | Subscribed |
| Subject Keyword | Grain boundaries Bulk solids Electron backscatter diffraction Packing (shipments) Packings (cushioning) Crystals Flip-chip Nanoindentation Mechanical properties Atoms X-ray diffraction Texture (materials) Electroplating Diffusion (physics) Stress Thin films Anisotropy Electrodiffusion Reliability Flip-chip devices Current density Heat treating (metalworking) |
| Content Type | Text |
| Resource Type | Article |
National Digital Library of India (NDLI) is a virtual repository of learning resources which is not just a repository with search/browse facilities but provides a host of services for the learner community. It is sponsored and mentored by Ministry of Education, Government of India, through its National Mission on Education through Information and Communication Technology (NMEICT). Filtered and federated searching is employed to facilitate focused searching so that learners can find the right resource with least effort and in minimum time. NDLI provides user group-specific services such as Examination Preparatory for School and College students and job aspirants. Services for Researchers and general learners are also provided. NDLI is designed to hold content of any language and provides interface support for 10 most widely used Indian languages. It is built to provide support for all academic levels including researchers and life-long learners, all disciplines, all popular forms of access devices and differently-abled learners. It is designed to enable people to learn and prepare from best practices from all over the world and to facilitate researchers to perform inter-linked exploration from multiple sources. It is developed, operated and maintained from Indian Institute of Technology Kharagpur.
Learn more about this project from here.
NDLI is a conglomeration of freely available or institutionally contributed or donated or publisher managed contents. Almost all these contents are hosted and accessed from respective sources. The responsibility for authenticity, relevance, completeness, accuracy, reliability and suitability of these contents rests with the respective organization and NDLI has no responsibility or liability for these. Every effort is made to keep the NDLI portal up and running smoothly unless there are some unavoidable technical issues.
Ministry of Education, through its National Mission on Education through Information and Communication Technology (NMEICT), has sponsored and funded the National Digital Library of India (NDLI) project.
| Sl. | Authority | Responsibilities | Communication Details |
|---|---|---|---|
| 1 | Ministry of Education (GoI), Department of Higher Education |
Sanctioning Authority | https://www.education.gov.in/ict-initiatives |
| 2 | Indian Institute of Technology Kharagpur | Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project | https://www.iitkgp.ac.in |
| 3 | National Digital Library of India Office, Indian Institute of Technology Kharagpur | The administrative and infrastructural headquarters of the project | Dr. B. Sutradhar bsutra@ndl.gov.in |
| 4 | Project PI / Joint PI | Principal Investigator and Joint Principal Investigators of the project |
Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon |
| 5 | Website/Portal (Helpdesk) | Queries regarding NDLI and its services | support@ndl.gov.in |
| 6 | Contents and Copyright Issues | Queries related to content curation and copyright issues | content@ndl.gov.in |
| 7 | National Digital Library of India Club (NDLI Club) | Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach | clubsupport@ndl.gov.in |
| 8 | Digital Preservation Centre (DPC) | Assistance with digitizing and archiving copyright-free printed books | dpc@ndl.gov.in |
| 9 | IDR Setup or Support | Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops | idr@ndl.gov.in |
|
Loading...
|