48 Result(s)
within
Young-Ho Kim
Characterization and Evaluation of Materials
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Article
Electrical Characteristics of a Ga-free T2SL Mid-wave Infrared nBn Detector Based on an InAs/AlAsSb/InAsSb Barrier
Ga-free InAs/InAsSb type-II superlattice (T2SL) has been used as an absorption layer of a high-operating-temperature mid-wavelength infrared nBn detector because it has a long Shockley–Read–Hall limited minori...
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Article
Plasma Treatment for Surface Stabilization in InAs/GaSb Type-II Superlattice LWIR and VLWIR Photodetectors
An InAs/GaSb nBn structure was investigated as a replacement for mercury cadmium telluride (MCT) in long-wavelength infrared (LWIR) and very long-wavelength infrared (VLWIR) detectors, which is advantageous fo...
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Article
Microstructure and shear strength of Au-20wt%Sn solder joints fabricated by thermo-compression bonding for LED packages
Solder joints of Au-20wt%Sn (Au-20Sn) between real light-emitting diode Si chips and AlN substrates were fabricated using thermo-compression (TC) bonding. We investigated the microstructure of TC-bonded solder...
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Article
Growth of intermetallic compounds and brittle fracture behavior of Sn-Ag-Cu/ENIG joint with columnar Ni-P layer
A growth of intermetallic compounds (IMCs) at the interface between electroless Ni/immersion Au (ENIG) and Sn-3.0Ag-0.5Cu (SAC305) solder and related brittle fracture behavior of solder joint with microstructu...
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Article
Open AccessQuality control and evaluation of Inonotus obliquus using HPLC method with novel marker compounds
Current quality control of Inonotus obliquus requires chromogen complex content limit of 10% in accordance with the State Pharmacopoeia of the Union of Soviet Socialist Republics. However, this causes ambiguous r...
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Article
Effect of soybean oil as a carbon source on the electrochemical property of LiNi1/3Co1/3Mn1/3O2 cathode material for lithium ion battery
In this study, soybean oil, which is used in a large variety of processed foods, is used as a carbon source. Soybean oil is successfully coated onto the surface of LiNi1/3Co1/3Mn1/3O2 (NCM) by a simple method. Th...
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Article
Epoxy/silane pre-synthesis improving thermal properties and adhesion strength of silica-filled non-conductive adhesive for fine-pitch thermocompression bonding
We modified an epoxy with silane to improve the bondability and thermal properties of a non-conductive adhesive (NCA) for fine-pitch thermocompression (TC) bonding. The main objectives of this modification wer...
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Article
Void fraction of a Sn–Ag–Cu solder joint underneath a chip resistor and its effect on joint strength and thermomechanical reliability
The void fraction in the solder joint of a chip resistor and its effect on the solder joint strength and reliability were investigated. The solder joint of a chip resistor has two regions: solder beneath the c...
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Article
Shear strength between Sn–3.0Ag–0.5Cu solders and Cu substrate after two solid-state aging processes for fan-out package process applications
Shear strength between Sn–3.0Ag–0.5Cu (SAC) solders and Cu/Ti in under bump metallization (UBM) samples aged using two solid-state aging processes was investigated. One method aged the samples at 200 °C for up...
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Article
Electromigration reliability of Sn–3.0Ag–0.5Cu/Cu–Zn solder joints
The electromigration reliability and failure modes of Sn–3.0Ag–0.5Cu (SAC)/Cu–Zn solder joints were investigated at 146 °C and a current density of 1.1 × 104 A/cm2. After aging at 146 °C for 150 h without electri...
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Article
Effects of Solder Volume and Reflow Conditions on Self-Alignment Accuracy for Fan-Out Package Applications
The effects of solder volume and reaction time between molten solder and a metal pad at the peak temperature of reflow on the self-alignment effect have been investigated in flip chip bonding. A glass die with...
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Article
Effect of Ni-P Plating Temperature on Growth of Interfacial Intermetallic Compound in Electroless Nickel Immersion Gold/Sn-Ag-Cu Solder Joints
The growth of interfacial intermetallic compound and the brittle fracture behavior of Sn-3.0Ag-0.5-Cu solder (SAC305) joints on electroless nickel immersion gold (ENIG) surface finish have been investigated us...
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Article
The effect of solder wetting on nonconductive adhesive (NCA) trap** in NCA applied flip-chip bonding
Flip-chip bonding using a nonconductive adhesive (NCA) and the effect of solder wetting on NCA trap** were studied. Three different solder materials with different melting point were used for the bonding pro...
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Article
Effect of Zn concentration on the interfacial reactions between Sn–3.0Ag–0.5Cu solder and electroplated Cu–xZn wetting layers (x = 0–43 wt%)
Cu–xZn wetting layers (x = 0, 20, 30, and 43 wt%) were electroplated in a non-cyanide solution and the interfacial reaction with Sn–3.0Ag–0.5Cu (SAC) solder was investigated after reflow and isothermal aging. Aft...
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Article
Low temperature chip on film bonding technology for 20 µm pitch applications
We developed a low temperature and low cost chip on film (COF) bonding technology using Sn/Cu bumps and nonconductive adhesives (NCAs) for 20 µm pitch applications. 20 µm pitch Sn/Cu bumps were formed by elect...
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Article
Improved drop reliability of Sn–Ag–Cu solder joints by Zn addition to a Cu wetting layer
Cu–20 wt% Zn solder wetting layers were fabricated by electroplating in cyanide and non-cyanide solutions, and board-level drop impact reliability was evaluated for Sn–Ag–Cu (SAC) solder joints formed on Cu–Zn...
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Article
Synthesis of dual nanoparticles embedded in polyimide and their optical properties
We investigated the formation of Cu or ZnO nanoparticles and mixture of Cu and ZnO nanoparticles dispersed in polyimide (PI) films using Cu(NO3)2 and Zn(NO3)2 salts. Each metal salt or the mixture of Cu(NO3)2 and...
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Article
Chip to Chip Bonding Using Cu Bumps Capped with Thin Sn Layers and the Effect of Microstructure on the Shear Strength of Joints
Chip to chip bonding techniques using Cu bumps capped with thin solder layers have been frequently applied to 3D chip stacking technology. We studied the effect of joint microstructure on shear strength. Joint...
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Article
Effects of chloride and crevice on corrosion resistance of stainless steels buried in soil within Seoul Metropolitan
Field and laboratory tests were conducted to find the factors affecting corrosion of stainless steels in soil. During one-year exposure, corrosion occurred within a joint and on the surface of type 304 pipe wi...
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Article
The effects of solder deformation on the wetting characteristics and interfacial reaction of Sn–3.5Ag solders on Cu substrates in fluxless soldering
The effects of solder deformation on the wetting characteristics during fluxless soldering were studied when deformed Sn–3.5Ag solder balls were reacted with Cu or oxidized Cu substrates. The Cu surfaces were ...
