- document
-
Luo, Runding (author), Hu, D. (author), Qian, Cheng (author), Liu, Xu (author), Fan, Xuejun (author), Zhang, Kouchi (author), Fan, J. (author)Nano-metal materials have received considerable attention because of their promising performance in wide bandgap semiconductor packaging. In this study, molecular dynamics (MD) simulation was performed to simulate the nano-Cu sintering mechanism and the subsequent mechanical behaviors. Hybrid sintering, comprising nanosphere (NS) and...journal article 2024
- document
-
Liu, Minne (author), Li, Wenyu (author), Chen, Wei (author), Ibrahim, Mesfin S. (author), Xiong, Jingkang (author), Zhang, Kouchi (author), Fan, Jiajie (author)During the operation of an LED array, its thermal and optical performances are always not equal to the superposition of the individual LED's characteristics because of a significant thermal coupling effect between the arrays. Based on this, this paper proposes an electrical–photo-thermal model, with considering both junction temperature and...journal article 2024
- document
-
Chen, Wei (author), Liu, Xu (author), Hu, D. (author), Liu, X. (author), Zhu, Xi (author), Fan, Xuejun (author), Zhang, Kouchi (author), Fan, J. (author)During operation in environments containing hydrogen sulfide (H<sub>2</sub>S), such as in offshore and coastal environments, sintered nanoCu in power electronics is susceptible to degradation caused by corrosion. In this study, experimental and molecular dynamics (MD) simulation analyses were conducted to investigate the evolution and...journal article 2024
- document
-
Chen, Wei (author), Liu, Xu (author), Yang, Zhoudong (author), Liu, X. (author), Hu, D. (author), Zhu, Xi (author), Fan, X. (author), Zhang, Kouchi (author), Fan, J. (author)The power semiconductor joining technology through sintering of copper nanoparticles is well-suited for die attachment in wide bandgap (WBG) semiconductors, offering high electrical, thermal, and mechanical performances. However, sintered nanocopper will be prone to degradation resulting from corrosion in sulfur-containing corrosive...journal article 2024
- document
-
Liu, Xu (author), Hu, D. (author), Li, Z. (author), Fan, Xuejun (author), Zhang, Kouchi (author), Fan, J. (author)The nano-copper particles are widely used in the sintering processes of packaging wide bandgap semiconductors. Despite the significant success in the industry, the mechanism bridging the sintering process to the mechanical properties of sintered nano-copper is not yet well-modeled. In this paper, the impacts of different sintering temperatures...conference paper 2024
- document
-
Hu, D. (author), Qian, Cheng (author), Liu, X. (author), Du, L. (author), Sun, Zhongchao (author), Fan, X. (author), Zhang, Kouchi (author), Fan, J. (author)As a promising technology for high-power and high-temperature power electronics packaging, nanocopper (nanoCu) paste sintering has recently received increasing attention as a die-attachment. The high-temperature deformation of sintered nanoCu paste and its underlying mechanisms challenge the reliability of high-power electronics packaging. In...journal article 2023
- document
-
Wang, Xinyue (author), Yang, Zhoudong (author), Wang, Boya (author), Chen, Wei (author), Zhang, Kouchi (author), Zhang, Jing (author), Fan, J. (author), Liu, P. (author)Power modules applied in offshore applications are facing risks of corrosion failures on die-attach materials due to high humidity and H<sub>2</sub>S exposure. To investigate such corrosion behavior for sintered die-attach materials, we conducted a study with four groups of samples fabricated using copper and silver metal particles under...journal article 2023
- document
-
Liu, Minne (author), Ibrahim, Mesfin S. (author), Wen, Minzhen (author), Li, Sheng (author), Wang, An (author), Zhang, Kouchi (author), Fan, J. (author)Spectral power distribution (SPD) is the radiation power intensity at different wavelengths, containing the most basic photometric and colorimetric performance of the illuminant, which is able to predict the lifetime of LEDs. This paper proposes an SPD model assisted by machine learning algorithms to detect the early failure of white LEDs. The...conference paper 2023
- document
-
Qian, Cheng (author), Hu, D. (author), Liu, Xu (author), Fan, Xuejun (author), Zhang, Kouchi (author), Fan, J. (author)Nano-metal materials sintering has received increasing attention in recent years for its promising performance in the wide bandgap semiconductor packaging. In this paper, molecular dynamics (MD) simulation method were applied to simulate the nano-Cu sintering mechanism and the subsequent mechanical behavior. Hybrid sintering, comprising...conference paper 2023
- document
-
Li, Shizhen (author), Liu, Yang (author), Ye, H. (author), Liu, X. (author), Sun, Fenglian (author), Fan, Xuejun (author), Zhang, Kouchi (author)This paper studied the behaviors of sintering between Ag nanoparticle (NP) and nanoflake (NF) in the same size by molecular dynamics simulation. Before the sintering simulation, the melting simulation of NF was carried out to calculate the melting points of NFs and investigate the thermostability of NF. The Lindemann index and potential...journal article 2022
- document
-
Li, Mingliang (author), Ren, S. (author), Liu, X. (author), Wu, Zhe (author), Zhang, Haopeng (author), Fan, Weiyu (author), Lin, P. (author), Xu, Jian (author)This study aims to comprehensively investigate the rejuvenation efficiency of various self-developed compound rejuvenators on the physical, mechanical, and aging properties of aged bitumen, asphalt mortar, and mixture. The results revealed that the restoration capacity of vacuum distilled-oil rejuvenators on high-and-low temperature performance...journal article 2022
- document
-
Fan, Jiajie (author), Jiang, Dawei (author), Zhang, Hao (author), Hu, D. (author), Liu, X. (author), Fan, Xuejun (author), Zhang, Kouchi (author)Nano-copper sintering is one of new die-attachment and interconnection solutions to realize the wide bandgap semiconductor power electronics packaging with benefits on high temperature, low inductance, low thermal resistance and low cost. Aiming to assess the high-temperature reliability of sintered nano-copper die-attachment and...journal article 2022
- document
-
Hou, F. (author), Zhang, Hengyun (author), Huang, Dezhu (author), Fan, J. (author), Liu, Fengman (author), Lin, Tingyu (author), Cao, Liqiang (author), Fan, Xuejun (author), Ferreira, Braham (author), Zhang, Kouchi (author)In this article, a microchannel thermal management system (MTMS) with the two-phase flow using the refrigerant R1234yf with low global warming potential is presented. The thermal test vehicles (TTVs) were made of either single or multiple thermal test chips embedded in the substrates, which were then attached to the MTMS. The system included...journal article 2020
- document
-
Fan, B. (author), Zhang, K. (author), Liu, Q. (author), Eelkema, R. (author)Introduction of dynamic thiol-alkynone double addition cross-links in a polymer network enable the formation of a self-healing injectable polymer hydrogel. A four-arm polyethylene glycol (PEG) tetra-thiol star polymer is cross-linked by a small molecule alkynone via the thiol-alkynone double adduct to generate a hydrogel network under ambient...journal article 2020
- document
-
Zhang, H. (author), Liu, Y. (author), Wang, Lingen (author), Sun, Fenglian (author), Fan, Xuejun (author), Zhang, Kouchi (author)The nanoindentation test was conducted in this paper to investigate the indentation hardness, plasticity and initial creep properties of pressure sintered nanosilver joint at various test temperatures. The effects of strain rate on the indentation hardness were first investigated. Then yield stress of nanosilver sintered joint was studied in...journal article 2019
- document
-
Zhang, H. (author), Liu, Y. (author), Wang, Lingen (author), Sun, Fenglian (author), Fan, Jiajie (author), Placette, Mark D. (author), Fan, Xuejun (author), Zhang, Kouchi (author)Modern power electronics has the increased demands in current density and high-temperature reliability. However, these performance factors are limited due to the die attach materials used to affix power dies microchips to electric circuitry. Although several die attach materials and methods exist, nanosilver sintering technology has received...journal article 2019
- document
-
Liu, Y. (author), Zhang, H. (author), Wang, Lingen (author), Fan, Xuejun (author), Zhang, Kouchi (author), Sun, Fenglian (author)Purpose: Crack and stress distribution on dies are key issues for the pressure-assisted sintering bonding of power modules. The purpose of this research is to build a relationship among stress distributions, sintering sequences and sintering pressures during the sintering processes. Design/methodology/approach: Three sintering sequences, S(a)...journal article 2019
- document
-
Yang, Ning (author), Yang, Daoguo (author), Zhang, Kouchi (author), Chen, Liangbiao (author), Liu, Dongjing (author), Cai, Miao (author), Fan, Xuejun (author)The effects of graphene stacking are investigated by comparing the results of methane adsorption energy, electronic performance, and the doping feasibility of five dopants (i.e., B, N, Al, Si, and P) via first-principles theory. Both zigzag and armchair graphenes are considered. It is found that the zigzag graphene with Bernal stacking has...journal article 2018
- document
-
Liu, Yang (author), Zhang, H. (author), Wang, Lingen (author), Fan, Xuejun (author), Zhang, Kouchi (author), Sun, Fenglian (author)The microstructure, thickness, porosity, and shear performance of the silver (Ag) sintering layers under different sintering pressures were investigated. Experimental results demonstrated that the thickness and the porosity of the sintering layer decreased when the sintering pressure varied from 5 MPa to 30 MPa. This densification phenomenon...journal article 2018
- document
-
Zhang, H. (author), Liu, Yang (author), Wang, Lingen (author), Fan, Jiajie (author), Fan, Xuejun (author), Sun, Fenglian (author), Zhang, Kouchi (author)High reliable packaging materials are needed for electronics when they work at harsh environments. Among which, the nanosilver material has been widely studied and applied in power electronics due to its low processing temperature and high reliability. This paper investigates the bonding properties of nanosilver sintered hermetic cavity. There...journal article 2018