2012 14th International Conference on Electronic Materials and Packaging (EMAP)最新文献

{"title":"Optical module for healthcare electronics","authors":"Lydia Leung, Sunny L. H. Chu, Luis Ng, Raymond To, Enboa Wu","doi":"10.1109/EMAP.2012.6507842","DOIUrl":"https://doi.org/10.1109/EMAP.2012.6507842","url":null,"abstract":"Optical module composed of light emitting diodes and photo-detector is the key component in measuring health information. We have developed a thin optical module with built-in EMI shield for measuring reflective blood oxygen saturation, pulse rate and breathing rate. With proper design in the shape of the encapsulation on the optical module, cross-coupling can be minimized. Also, with the new packaging design, the optical module can be easily modified for measuring blood oxygen saturation at different parts of the body. Reliability tests have been conducted on the optical module to investigate and evaluate its robustness including the shift in peak wavelength and emission power which will affect the accuracy of the pulse oximeter.","PeriodicalId":182576,"journal":{"name":"2012 14th International Conference on Electronic Materials and Packaging (EMAP)","volume":"333 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"134075081","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 the reliability of thin-film interconnections based on the control of the crystallinity of the thin films","authors":"O. Asai, Naokazu Murata, Ken Suzuki, H. Miura","doi":"10.1115/IPACK2013-73149","DOIUrl":"https://doi.org/10.1115/IPACK2013-73149","url":null,"abstract":"In this study, the degradation mechanism of electronic performance of electroplated copper interconnections was investigated by considering their crystallinity of grain boundaries. The crystallinity of the interconnections was evaluated quantitatively by applying an EBSD (Electron Back-scattered Diffraction) method. It was found that the crystallinity of the interconnections varied drastically depending on the seed layer material for electroplating. A new design guideline for highly reliable electroplated copper thin film interconnections was proposed based on the measured results.","PeriodicalId":182576,"journal":{"name":"2012 14th International Conference on Electronic Materials and Packaging (EMAP)","volume":"61 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"128851617","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":"Impact from IMC thickness on the reliability of wire bonding","authors":"J. Xiao, J. Huang, J. Liao, Y. Lin","doi":"10.1109/EMAP.2012.6507876","DOIUrl":"https://doi.org/10.1109/EMAP.2012.6507876","url":null,"abstract":"Materials to replace gold wires in wire bonding devices have been pursued for years in industries for cost reduction. The most important factors, besides the price and electric and thermal performance of the material itself, is the growth rate of the intermetallic compound (IMC) at the interface, which would severely affect the reliability of the devices. In this paper, we studied and analyzed the IMC growth for Au, Cu and Ag wires with Al pads. High temperature storage (HTS) aging experiments were employed for accelerated test. Scanning Electron Microscopy (SEM) and Energy Dispersive X-ray Spectrometer (EDS) were adopted to investigate the IMC at the interface of the wires and the pads. IMC growth including Kirkendall holes and cracks were examined and compared. It is found that in the samples with gold wires, Kirkendall holes and cracks formed at the interface, which led to a high increase of electrical resistance and possible ball lift. When using copper wires instead of Au wires, although the IMC growth rate reduced, the limitation of Cu wires is due to the high hardness and yield strength at a high temperature. On the other hand, the surface of copper is easy to produce a thick oxide layer, sometimes leading to earlier failures than using Au wires. Compared with copper wires, silver wires are softer. And it is found that IMC growth rate of samples with silver wires is lower than those with gold wires. Correlations between the IMC and the reliability will be discussed.","PeriodicalId":182576,"journal":{"name":"2012 14th International Conference on Electronic Materials and Packaging (EMAP)","volume":"15 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123382578","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":"Potential-assisted assembly of thiol-based materials for reliable copper-epoxy interface","authors":"Stephen C. T. Kwok, M. Yuen","doi":"10.1109/EMAP.2012.6507832","DOIUrl":"https://doi.org/10.1109/EMAP.2012.6507832","url":null,"abstract":"Despite the fact that copper has continuously being used as leadframe materials in electronic packaging, adhesion strength between copper-epoxy joint is prone to be weaken during reliability test. In order to solve this problem, thiol-based self-assembled material (SAM) is applied as coupling agent between copper and epoxy system. A remarkable interfacial adhesion improvement was reported by different groups [1–2]. This work reports on adhesion enhancement effects of self-assembled organothiol treatment on copper/epoxy interface, as well as a significant reduction in treatment time under the influence of electric potential. The interfacial adhesion has a maximum enhancement of 20-fold through the treatment due to improved linkage between copper substrate and epoxy layer by chemisorbed organothiol molecules. The treatment time was greatly reduced by 32 times to 1800s with the proposed preparation method and maximum adhesion strength up to 97.2±6.1 Jm−2 was demonstrated. The use of potential enhances preparation efficiency with adhesion improvement comparable to passive adsorption method make up in 16hrs.","PeriodicalId":182576,"journal":{"name":"2012 14th International Conference on Electronic Materials and Packaging (EMAP)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131188922","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 chemical etching solution on Cu/Al IMC result","authors":"Wong Boh Kid, Yap Jia Lin, Eu Poh Leng, Yow Kai Yun, C. Yong","doi":"10.1109/EMAP.2012.6507929","DOIUrl":"https://doi.org/10.1109/EMAP.2012.6507929","url":null,"abstract":"To ensure a reliable Cu wire bond on Al bond pad, Freescale has learnt that good IMC plays a very important role. However, unlike Au/Al IMC measurement method which has been well established, Cu/Al IMC measurement method is still relatively new in semiconductor industry. This study was aimed to establish an effective chemical solution to etch off Cu bonded ball to check IMC coverage at the entire ball-bond-to-bond-pad interface, with consistent and reliable result. In this paper, effect of chemical etching solution on Cu/Al IMC result was studied by using different combination of Nitric Acid molar concentration. The key factors were found to be etching temperature and different combination of Nitric Acid molar concentration. The chemical etching method was carefully designed to etch away Cu wire while only retaining the Cu/Al IMC on Al bond pad. The test vehicle used was 668TePBGA-II. Samples were baked at 175C for 48hrs. Cu ball bond was then removed with different combination of Nitric Acid molar concentration. After etching, IMC was inspected under 500x microscope magnification. Images were taken and software was used to accurately calculate IMC % with reference to effective bonded ball area. SEM/EDX was used to confirm the presence of Cu/Al IMC on the surface of Al bond pad. EDX was used to analyze the phase diagram of Cu-Al system to identify the possible IMCs formed between Cu and Al. Through this study, Cu/Al IMC phases were found to be Cu9Al4 (69.2 atomic % Cu), Cu3Al2 (60.0 atomic % Cu), Cu4Al3 (57.1 atomic % Cu), CuAl (50.0 atomic % Cu) and CuAl2 (33.3 atomic % Cu). The result showed that Nitric Acid concentration from 9 to 11 mol/L yielded the most reliable and repeatable IMC result. Apart from that, other advantages of the final recipe included low price and reasonable short etching time.","PeriodicalId":182576,"journal":{"name":"2012 14th International Conference on Electronic Materials and Packaging (EMAP)","volume":"22 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"125274303","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 the lattice mismatch between copper thin-film interconnection and base material on the crystallinity of the interconnection","authors":"Chuanhong Fan, O. Asai, Ken Suzuki, H. Miura","doi":"10.1299/JSMETOHOKU.2012.48.130","DOIUrl":"https://doi.org/10.1299/JSMETOHOKU.2012.48.130","url":null,"abstract":"Electroplated copper thin films have become indispensable for the interconnections in next-generation semiconductor devices because of its low electric resistivity and high thermal conductivity. Since the electrical properties of the electroplated copper thin films vary drastically depending on their micro texture, the effect of the base layer material (a copper diffusion preventing layer and an electroplating seed layer) on the crystallinity of the electroplated copper thin films was investigated quantitatively in order to assure and improve the performance and reliability of electroplated copper thin-film interconnections.","PeriodicalId":182576,"journal":{"name":"2012 14th International Conference on Electronic Materials and Packaging (EMAP)","volume":"1 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"114975760","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 evolution of IMCs' morphologies and types in SAC and SAC+ solder bumps during thermal shock process","authors":"Ying Zhong, Chun Qing Wang, J. Caers, Xiujuan Zhao","doi":"10.1109/EMAP.2012.6507861","DOIUrl":"https://doi.org/10.1109/EMAP.2012.6507861","url":null,"abstract":"The types and morphologies evolution of IMCs affect the reliability of SAC bumps during the process of thermal shock effectively, especially when Ni element was added to manufacture SAC+ bumps. The IMCs at the interface between the solder and the Au/Ni/Cu coating as well as the ones in the solder bulk were studied. The IMCs' morphology evolution was observed by SEM both in cross-section view and top view; the types and composition transformation were tested by EDX and line scanning; the effect of Ni was researched by comparing the difference between SAC and SAC+. As a result, the IMCs in SAC solder bumps right after soldering was mainly needle like (Cu, Ni)<inf>6</inf>Sn<inf>5</inf> at the interface and uniform Ag<inf>3</inf>Sn net in the bulk; for the SAC+ solder, (Ni,Cu)<inf>3</inf>Sn<inf>4</inf> blocks and needle like (Cu, Ni)<inf>6</inf>Sn<inf>5</inf> were both found, and lots of (Ni,Cu)<inf>3</inf>Sn<inf>4</inf> particles broke the Ag<inf>3</inf>Sn net in the bulk. During thermal shock, the IMC of SAC+ is thicker than that of SAC at beginning, but its growth rate later was less. After 1500 cycles, the (Ni, Cu)<inf>3</inf>Sn<inf>4</inf> can be separated from the interface layer and then be turned into (Cu,Ni)<inf>6</inf>Sn<inf>5</inf>; at area without the cover of (Ni, Cu)<inf>3</inf>Sn<inf>4</inf>, (Cu,Ni)<inf>6</inf>Sn<inf>5</inf> can grow much faster with a new (Ni, Cu)<inf>3</inf>Sn<inf>4</inf> layer fomed under it; the thickness of the SAC+ bumps affects the thickness as well as morphology of the IMCs. Especially (Cu,Ni)<inf>6</inf>Sn<inf>5</inf> in thinner bumps is polygon but in thicker bumps was needle type.","PeriodicalId":182576,"journal":{"name":"2012 14th International Conference on Electronic Materials and Packaging (EMAP)","volume":"242 ","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"131485558","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":"Effects of moisture absorption and temperature on the adhesion strength between Die Attach Film (DAF) and silicon die","authors":"Chunhua Guan, Martin Li, Kewei Chen, Haibin Chen, Jingshen Wu","doi":"10.1109/EMAP.2012.6507837","DOIUrl":"https://doi.org/10.1109/EMAP.2012.6507837","url":null,"abstract":"Nowadays, Die Attach Film (DAF) has been commonly employed as a bonding media for thin die attach package and it has the tendency of replacing the normal die attach glues. Package miniaturization and die thickness reduction are the main drivers for DAF implementation in electronic packaging industry, especially in applications which require that the die thickness should be less than 100µm. However, there are still some potential reliability problems in the industry over the application of this new material, particularly the package crack issue which is directly related to material properties of DAF, such as the interfacial adhesion strength and the water absorption rate. In this study, die shear test is employed to determine the interfacial adhesion strength between DAF and silicon die. The samples with DAF and die were adhered on a copper leadframe with a load of 100±5g, heated to 100°C then held at 175°C for 5 hours. With this sample preparation method, the failure was found to occur at the DAF/Die interface during the die shear test, so that the adhesion strength between DAF and die can be well characterized. Measurements with different shear speeds were firstly conducted to find out the best conditions for this test. The effects of the moisture absorption and test temperature on the adhesion strength between DAF and Die were thereby studied. The results show that after being soaked at 85°C/85RH for 168 hours, the shear strength between the DAF and silicon die decrease from 110N to 21N. When the test temperature is 250°C, the shear stress is only 8% of that determined at 25°C. To understand these moisture absorption and temperature effects, the material properties of the DAF, including coefficient of thermal expansion, glass transition temperature, dynamic mechanical property, water absorption rate, were characterized. In summary, this study demonstrates the effect of moisture absorption and temperature on the adhesion strength between DAF and silicon die, which would provide useful and practical guidelines for industry for applications of DAF in different packages.","PeriodicalId":182576,"journal":{"name":"2012 14th International Conference on Electronic Materials and Packaging (EMAP)","volume":"5 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"115444898","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":"Assembly analysis of Cu/Ni/SnAg microbump for stacking thin chips in a fine pitch package using a wafer-level underfill","authors":"Chang-Chun Lee, Tsung-Fu Yang, Kuo-Shu Kao, Ren-Chin Cheng, C. Zhan","doi":"10.1109/EMAP.2012.6507854","DOIUrl":"https://doi.org/10.1109/EMAP.2012.6507854","url":null,"abstract":"To enhance assembly quality and mechanical reliability of microbumps during both stacking process of multi thin chips and temperature cycling tests, a novel fabricated technique of wafer level underfill (WLUF) is proposed to resolve the foregoing concerned problem. However, the occurrence of a serious warped condition or gap reduction between stacked chips is observed through the assembly procedures of WLUF with a thermal-compression approach. This is harmful to the objective achievements of a three-dimensional integrated circuits package. In order to address this urgent issue, the research presents a process-oriented stress simulation based on finite element method to find the root cause as compared with experimental data. The analytic results indicate that the major influenced factors inducing thermo-mechanical stress within a chip-on-chip package are resulted from a huge temperature difference in WLUF process and mechanical properties of WLUF, respectively. It is found that the use of WLUF with a low coefficient of thermal expansion and a low Young's modulus is beneficial to reduce plastic strain of critical microbumps. Moreover, through the utilization of layout designs of microbumps array with the arrangements of dummy joints, the significant improvements of co-planarity in a whole packaging structure could be achieved. The simulated predictions point out that as more than three of dummy joints is put nearby the outermost microbump, a warpage variation between the packaging center and chip edge at the top surface of a package under a load of a 2.0 kg bonding force would be smaller than 70 nm. At the same time, a minimum equivalent plastic strain of ∼0.87 % generated on the critical microbump is obtained during a thermal cycling load.","PeriodicalId":182576,"journal":{"name":"2012 14th International Conference on Electronic Materials and Packaging (EMAP)","volume":"332 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"123226435","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":"Different morphologies of nano-ZnO affection on properties of transparent epoxy resin encapsulants","authors":"Chongnan Peng, Guoping Zhang, R. Sun, Ricky S. W. Lee","doi":"10.1109/EMAP.2012.6507893","DOIUrl":"https://doi.org/10.1109/EMAP.2012.6507893","url":null,"abstract":"With the development of light emitting diodes (LEDs), it puts forward higher performance requirements on encapsulants, mainly epoxy resins. So far, people have made a great deal of efforts on improving the thermal conductivity, resistance of thermal and ultra-visible light (UV) aging, visible light (Vis) transparency and refractive index. It is an effective method of introducing inorganic fillers, like zinc oxide (ZnO) and titanium oxide (TiO2), into epoxy matrix to prepare nanocomposites. In this paper, two morphologies of nano-ZnO, particles and nanorods, were prepared. Nano-ZnO particles and rods were respectively dispersed into butanone with ultrasonic technique before added into the epoxy solution. The epoxy resins were made into ultra-thin film via spin-coating method. The results show that the nano-ZnO particles/epoxy nanocomposite ultra-thin films kept high visible transparency and high UV shielding at the condition of 1wt% addition, but no improvement on thermal conductivity. Contrarily nano-ZnO rods/epoxy nanocomposite ultra-thin films did not present so well in optical properties, but better on thermal conductivity. So we mixed the two kinds of nano-ZnO to improve the thermal conductivity at the presupposition of not harming the shielding of UV and keeping the transparency of Vis of the epoxy resins.","PeriodicalId":182576,"journal":{"name":"2012 14th International Conference on Electronic Materials and Packaging (EMAP)","volume":"67 1","pages":"0"},"PeriodicalIF":0.0,"publicationDate":"2012-12-01","publicationTypes":"Journal Article","fieldsOfStudy":null,"isOpenAccess":false,"openAccessPdf":"","citationCount":null,"resultStr":null,"platform":"Semanticscholar","paperid":"126206786","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}