A5067986643- Electronic Packaging and Soldering Technologies
- Antenna Design and Analysis
- Microwave Engineering and Waveguides
- 3D IC and TSV technologies
- Copper Interconnects and Reliability
- Aluminum Alloys Composites Properties
- Advanced Antenna and Metasurface Technologies
- Antenna Design and Optimization
- Microstructure and mechanical properties
- Electrodeposition and Electroless Coatings
- Metal and Thin Film Mechanics
- Advanced Welding Techniques Analysis
- Advanced ceramic materials synthesis
- Semiconductor materials and devices
- Nanofabrication and Lithography Techniques
- Ultra-Wideband Communications Technology
- Advanced Surface Polishing Techniques
- Bluetooth and Wireless Communication Technologies
- Advanced materials and composites
- Advanced Sensor and Energy Harvesting Materials
- Geophysical Methods and Applications
- Force Microscopy Techniques and Applications
- Millimeter-Wave Propagation and Modeling
- Intermetallics and Advanced Alloy Properties
- Thin-Film Transistor Technologies
National Yang Ming Chiao Tung University
2021-2024
National Central University
2015-2018
Delft University of Technology
2002-2016
California State University, Fullerton
2012
The design of a planar dual-band wide-scan phased array is presented. uses novel comb-slot-loaded patch elements supporting two separate bands with frequency ratio 1.4:1. antenna maintains consistent radiation patterns and incorporates feeding configuration providing good bandwidths in both bands. has been experimentally validated an X-band 9 × array. supports wide-angle scanning up to maximum 60 <sup xmlns:mml="http://www.w3.org/1998/Math/MathML"...
We adopted (111)-oriented Cu with high surface diffusivity to achieve low-temperature and low-pressure Cu/SiO2 hybrid bonding. Electroplating was employed fabricate arrays of vias 78% (111) grains. The bonding temperature can be lowered 200 °C, the pressure is as low 1.06 MPa. process accomplished by a 12-inch wafer-to-wafer scheme. measured specific contact resistance 1.2 × 10-9 Ω·cm2, which lowest value reported in related literature for Cu-Cu joints bonded below 300 °C. possess excellent...
The objective of this study is to investigate the effect long-term static bending on conductive characteristics indium tin oxide (ITO) thin film in flexible optoelectronics. Two types substrate are considered, namely ITO polyethylene naphthalate (ITO/PEN) and terephthalate (ITO/PET). Electrical properties ITO/PEN ITO/PET sheets measured situ under at various radii curvature. Experimental results indicate that no significant change electrical resistance found for compressive after 1000 h a...
Rotary electroplating was employed to fabricate high-strength nanotwinned copper (nt-Cu) foils serving as a current collector for high energy-density lithium ion batteries (LIBs). The effect of Cu concentration on the microstructural and mechanical properties nt-Cu then investigated. Formation nano-scaled grains found at bottom. Its size gradually increases toward top surface form mixture gradient columnar in upper region. Experimental results show that elongation increase with increasing...
The failure mechanisms of Cu-Cu bumps under thermal cycling test (TCT) were investigated. resistance change in chip corners was less than 20% after 1000 cycles. Many cracks found at the center bonding interface, assumed to be a result weak grain boundaries. Finite element analysis (FEA) performed simulate stress distribution cycling. results show that maximum located close Cu redistribution lines (RDLs). With TiW adhesion layer between and RDLs, strength strong enough sustain stress....
In this study, we designed and electroplated various regular nanotwinned copper (nt-Cu) lines. These Cu lines were then covered with a polyimide (PI) layer heat-treated to some extents prior electromigration (EM) testing. The results show that the EM lifetime of nt-Cu is approximately 4.7 times longer than ones. We found has been enhanced by 273% using heat treatment. improvement attributed heat-treatment-led elimination nt–Cu transition (nanoscale grain region). diffusion paths atoms at...
In this study, the effect of intermetallic compound (IMC) bridging on cracking resistance microbumps with two different under bump metallization (UBM) systems, Cu/solder/Cu and Cu/solder/Ni, a thermal cycling test (TCT) is investigated. The height Sn2.3Ag solders was ~10 µm, which resembles that most commonly used microbumps. We adjusted reflow time to control IMC level. samples levels were tested TCT (−55–125 °C). After 1000 2000 cycles (30 min/cycle), then polished characterized using...
Highly (111)-oriented nanotwinned copper (nt-Cu) and non-conductive paste (NCP) were employed to fabricate hybrid Cu–Cu bonding. We tailored correlated the fracture modes, bonding strengths, microstructures of joints. A non-flow underfilling process was performed, low temperature achieved in a single heat treatment at 180 °C for 120 min without vacuum. found that under post-annealing treatment, recrystallization grain growth occurred. The interfaces partially removed joints further...
Copper-to-copper (Cu-to-Cu) direct bonding is a promising approach to replace traditional solder joints in three-dimensional integrated circuits (3D ICs) packaging. It has been commonly conducted at temperature over 300 °C, which detrimental electronic devices. In this study, highly (111)-oriented nanotwinned (nt) Cu films were fabricated and polished using chemical mechanical planarization (CMP) electropolishing. We successfully bonded remained columnar nt-Cu microstructure low of 150 °C...
Copper joints have replaced solder interconnects in integrated circuits due to their great electrical properties and lower-temperature processing. To isolate Cu from oxidizing during bonding processes, a (111)-oriented nanotwinned Ag (NT-Ag) thin layer was electroless-deposited on NT-Cu film. Such method outperforms the sputtering approach terms of expenditure, environmental impact, deposition rate. The microstructures films were then analyzed. Results show that columnar NT-Ag grains...
We report here an approach to inhibit Cu–Sn intermetallic compounds (IMCs) in flip chip solder joints under thermal-gradient annealing. reflowed two types of solders joints, Cu/SnAg/Cu and Cu/SnAg/Ni, oven (isothermal) on a hot plate (with thermal-gradient) at 260 °C. During the isothermal reflow, IMC growth rates top bottom sides joint were ∼4.0 × 10−2 8.9 μm/min, respectively. However, rate increased 7.8 10−1, 7.9 10−1 μm/min cold ends with low, medium, high thermal gradients, Yet,...
The effects of the sintering duration and powder fraction (Ag-coated Cu/SnAgCu) on microstructure reliability transient liquid phase sintered (TLPS) joints are investigated. results show that two main intermetallic compounds (IMCs, Cu6Sn5 Cu3Sn) formed in joints. ratio generally decreased with increasing time, Cu fraction, thermal treatment. void high-Cu-fraction increased stressing durations, respectively, whereas low-Cu-fraction counterparts were stable. We also found shear strength...
Polyimide (PI) has been adopted to protect the Cu from oxidation in packaging industry. Electromigration (EM) of redistribution layers (RDLs) capped with PI was investigated at 160 °C under 1.0 × 106 A/cm2. The results indicated that failure fine-pitched (2-µm) is different 10-µm RDLs, which void formation. 2-µm RDLs mainly caused by severe during EM. To analyze EM pitches, area nanotwinned copper (nt-Cu) and regular compared. We propose an equation estimate resistance increase various widths.