Browsing by Author "Lin, Wan-Hsuan"

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Failure mechanism of Cu/SnAg/Ni microbumps in three-dimensional integral circuits under electromigration
(2014)
Lin, Wan-Hsuan
;
Chao, Shu-Han
;
Zhan, Chau-Jie
;
Huang, Yu-wei
;
Chen, Chih
In this study, we use the Cu/SnAgiNi/Cu joint with a thickness of 7 mu m/8 mu m/2 mu m /5 mu m and 7 mu m/16 mu m/2 mu m /5 mu m. The diameter of the solder joint is about 30 mu m and the UBM opening is 18 mu m in diameter with 60 pm pitches. In order to measure the resistance changes, it was fabricated which constitute four probes. By using this method we can measure the resistance changes in microbump excluding the resistance changes in the wiring trace to make it more sensitive to subtle microstructure changes. We investigated the mechanisms of electromigration in microbumps with different stages when resistance increased 20%, 50% and 100% of the initial resistance. Solder joints were stressed with 0.56 A on 150 degrees C hot plate. The average current density is 8 x 10(4) A/cm(2), calculated based on the UBM opening. We ground the samples with 1000, 2000, and 4000 sand paper and then polished them with 1 mu m, 0.3 mu m, and 0.05 mu m Al2O3. We observed their morphologies with SEM and measured their component with EDX. In the bump with electron flow upward, we observed that microbumps were transformed into Cu6Sn5 IMCs and Cu3Sn IMCs joints. In addition, voids were formed at the interface between nickel and solder. We found that both void formation and UBM dissolution were occurred. In the bump with electron flow downward; microbumps were transformed into IMC joints without void formation. To sum up, this study provides a better understanding on the relationship between the behavior of resistance curve and the morphology changes in microbumps.
Hand-powered centrifugal microfluidic disc with magnetic chitosan bead-based ELISA for antibody quantitation
(2020-08-01)
Lin, Chia-Tung
;
Kuo, Shao-Hsuan
;
Lin, Pei-Heng
;
Chiang, Pei-Huan
;
Lin, Wan-Hsuan
Extreme point-of-care testing (POCT) is a medical test performed at or near patients at a resource-limited condition. POCT technology has advantages over traditional medical lab tests for molecular detection and infection diagnosis, such as being simple, portable, low-cost, and user-friendly. However, some POCT devices might rely on bulky equipment, and some might be easily influenced by components in biofluid, which might result in higher prices and lower accuracy. In this paper, we demonstrated a low-cost method for detecting bacterial infection in the early stage. We designed a hand-powered centrifugal microfluidic (CMF) disc with magnetic chitosan beads (MCBs) to detect specific circulating antibodies in human whole blood. Nine identical units was used for calibration curve plotting and sample testing. The MCBs, generated with another microfluidic chip and coated with MBL proteins (biomarker of drug-resistant Streptococcus pneumoniae, DRSP, taken as an example for bacterial infection), were served as the substrate of sandwich-structured enzyme-linked immunosorbent assays (ELISA) and as the micro stirring sphere at the same time. The limit of detection (LOD) in PBS and human whole blood were 22.67 ng/mL and 24.83 ng/mL, respectively. The comparison between calibration curves from the antibody spiked in human whole blood and that in PBS was shown to prove the high compatibility and low interference of biofluid, and the recovery rate was 92 %. In conclusion, since our low-cost, time-saving, and user-friendly hand-powered CMF device with minimally consumed electricity detected the target antibody precisely, we believe that other similar assays would be feasible as well. Therefore, we are firmly convinced that this alternative POCT device may lead to the development of next-generation healthcare diagnoses.
On Common Profile Matching among Multiparty Users in Mobile D2D Social Networks
(2014)
Chen, Yan-Ann
;
Lin, Wan-Hsuan
;
Tseng, Yu-Chee
;
資訊工程學系
;
Department of Computer Science
Recently, mobile social networks (MSNs) have been widely discussed due to the rapid growth of smart mobile devices. This work focuses on mobile D2D social networks (MDSNs), where users in an MSN are physical neighbors. An important social application of MDSNs is common profile matching (CPM), which refers to the scenario where a group of smartphone users meet in a small region (such as a ball room) and these users are interested in identifying the common attributes among them from their personal profiles efficiently via short-range (such as D2D) communications. For example, a group of strangers may want to find common hobbies, friends, or countries they visited before, and a group of students may want to know the common courses they have ever taken. Assuming that users in an MDSN form a fully connected network, we formulate three versions, namely all common, beta-common, and top-gamma-popular, of the CPM problem. The first problem is an extension of an earlier work, while the latter two problems are newly defined. We present solutions based on the basic and the iterative Bloom filters. Evaluation results show that our mechanisms are quite communication-efficient.