A5102758419- Semiconductor materials and devices
- Silicon and Solar Cell Technologies
- Electronic Packaging and Soldering Technologies
- Thin-Film Transistor Technologies
- Semiconductor materials and interfaces
- Advancements in Semiconductor Devices and Circuit Design
- Heat Transfer and Optimization
- Photovoltaic System Optimization Techniques
- solar cell performance optimization
- Heat Transfer and Boiling Studies
- 3D IC and TSV technologies
- Heat Transfer Mechanisms
- ZnO doping and properties
- Copper Interconnects and Reliability
- Transition Metal Oxide Nanomaterials
- Electrical and Thermal Properties of Materials
- Material Properties and Processing
- Aluminum Alloys Composites Properties
- Silicon Carbide Semiconductor Technologies
- Solar Thermal and Photovoltaic Systems
- Optimization and Packing Problems
- Aluminum Alloy Microstructure Properties
- Computational Geometry and Mesh Generation
- Advanced Welding Techniques Analysis
- Ferroelectric and Negative Capacitance Devices
Chung-Ang University
1997-2024
The University of Tokyo
2021-2024
Tokyo University of Information Sciences
2023
Kwangwoon University
2017-2020
Korea Institute of Industrial Technology
2015
Hanyang University
2012-2015
Manifold microchannel heat sinks (MMCHSs) have attracted attention for the thermal management of high-performance electronics owing to their high dissipation rate and low pressure drop compared conventional microchannels. This study used a full 3D conjugated simulation analyze effects changes in geometry operating environment on hydraulic performance MMCHS. The findings provide holistic view MMCHS design improvement. Twelve manifold geometries were designed by changing direction width outlet...
Microchannel heat sinks have been recognized as efficient cooling platforms for thermal management of miniaturized devices because their compact structure. Unlike most microfabrication processes, laser micromachining is a versatile direct writing method to rapidly produce microchannels in brittle substrates such silicon wafers. In this study, an all-laser fabrication proposed fabricate microfluidic sink devices. Lasers are used engraving on wafer, drilling inlet/outlet holes quartz glass...
Thermal management problems in high-power flexible electronics are exacerbated by the design complexity and requirement of stringent temperature control to prevent skin burns. Thus, effective heat dissipation methods applicable on polymer substrates an essential device component. Accordingly, this study investigates pool boiling transfer characteristics potential enhancements, enabled laser-induced graphene (LIG), which is both highly porous bendable. Patterned LIG with a mesh spacing 200 μm...
Abstract The sub-threshold swing (SS) of Si n-MOSFETs is experimentally and systematically evaluated in a temperature range 4–300 K with varying the substrate impurity concentration ( N sub ) from ~10 16 to 18 cm −3 , obtain physical understanding SS at cryogenic temperatures. It clarified that drain current dependencies are well represented by model composed mobile tail states localized interface states, irrespective . densities these found increase increasing A origin band studied...
Abstract We experimentally characterize sub-threshold swing ( SS ) of Si n-channel MOSFETs with a substrate boron concentration 2 × 10 16 cm −3 as function drain current I DS and temperatures from 4 to 300 K in order verify the validity physical model . The minimum are obtained at around mV dec −1 including mobile band tail states localized interface Gaussian distribution, proposed by Beckers el., is employed represent experimental K. impact each parameter included on behavior examined...
This study investigated the suppression of growth intermetallic compound (IMC) layer that forms between epoxy solder joints and substrate in electronic packaging by adding graphene nano-sheets (GNSs) to 96.5Sn⁻3.0Ag⁻0.5Cu (wt %, SAC305) whose bonding characteristics had been strengthened with a polymer. IMC was induced isothermal aging tests at 150 °C, 125 °C 85 for 504 h (21 days). Activation energies were calculated based on thickness, temperature, time. The activation energy required...
The constrained two-dimensional cutting problem involves maximising the sum of profits obtained from small rectangular pieces cut a large plate where number each type piece cannot exceed prescribed quantity. This paper proposes best-first branch-and-bound algorithm to find optimal solution problem. proposed uses an efficient method remove duplicate patterns, and it improves existing upper bounds. It also prevents construction dominated patterns introduces new bounding strategy that can prune...
In this study, the characteristics of a photovoltaic (PV) ribbon (t = 0.25 mm) joint with 60Sn40Pb and 62Sn2Ag36Pb solders were evaluated using thermal shock tests. The tests performed under three conditions: −40–65 °C, −40–85 −40–105 °C. results these analyzed electroluminescence (EL) cross-sectional images. Following testing, broken metal fingers (MFs) confirmed near solder joint. PV module degradation was attributed to finger ratio (BFR) based on quantitative analysis dark rectangular...
To analyze the reinforcement effect of adding polymer to solder paste, epoxies were mixed with two currently available Sn-3.0Ag-0.5Cu (wt.% SAC305) and Sn-59Bi (wt.%) pastes specimens prepared by bonding chip resistors a printed circuit board. The repetitive thermal stress on joints was then analyzed experimentally using shock testing (−40 °C 125 °C) over 2000 cycles. viscoplastic stress–strain curves generated in simulated finite element analysis, hysteresis loop calculated. growth...
본 연구에서는 PV(photovoltaic)모듈에서 경년에 따른 효율 저하의 원인을 분석하기 위해 셀 레벨에서의 열충격 시험을 수행하였다. 시험의 조건은 <TEX>$-40^{\circ}C$</TEX>에서 <TEX>$85^{\circ}C$</TEX>로 각각 15분씩 30분을 1사이클로 하였으며, 시험 500 사이클 동안 100 간격으로 EL분석 및 I-V분석을 감소율은 단결정 Bare Cell이 8%, Solar 9%였으며, 다결정 6%, 13%의 감소율을 보였다. 후 Cell은 표면 손상으로 인한 효율저하를 확인할 수 있었다. Cell의 경우 표면의 손상이 없었지만, 효율이 저하된 것을 이는 Fill Factor 분석에 의해 경년 시 나타나는 누설전류에 의한 소모전력 증가로 저하에 영향을 준 것으로 판단된다. 또한, Cell보다 Cell에서의 감소율이 상대적으로 높게 나타난 결과는 손상 소모 전력의 인해 Cell 효율에 큰 미치는 향후 단면 분석법 다양한 조건의 기법을...
In this study, we conducted microwave annealing (MWA) on amorphous In–Ga–Zn–O (a-IGZO) thin films deposited by the sol-gel method, and then investigated effects of ambient conditions electrical properties reliability a-IGZO thin-film transistors (TFTs) optical chemical films. On other hand, pure N2 ambient-treated TFTs exhibited poorest transfer output characteristics, but improved with increasing O2 mixing ratio. terms stability, were excellent for both positive negative gate bias stresses,...
In this study, the characteristics of growing an intermetallic compound(IMC) layer at solder joint in photovoltaic (PV) ribbon were investigated through thermal ageing test. Also, growth rate IMC joint, which depend on temperature and time, was predicted That test performed under three different conditions: 90 °C, 120 °C 150 °C. we prepare two type composition(60Sn40Pb, 62Sn2Ag36Pb) to analyze Ag addition effect forming layer. Following testing, formed Ag3Sn sintered by Sn diffusion...