| 1. |
- Lu, Xiuzhen, et al.
(författare)
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The influence of sintering process on thermal properties of nano-silver paste
- 2018
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Ingår i: 2018 19TH INTERNATIONAL CONFERENCE ON ELECTRONIC PACKAGING TECHNOLOGY (ICEPT). - 9781538663868 - 9781538663868 ; , s. 1157-1160
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Konferensbidrag (refereegranskat)abstract
- Nano-silver paste with low sintering temperature and high operation temperature was introduced to the application of bonding materials for GaN and SiC devices. Thermal properties are critical issues for die attach materials due to the heat dissipation requirements of high power devices. The influence of sintering process parameters for nano-silver paste on the thermal properties was investigated. The thermal conductivity of sintered nano-silver paste increased with the increase of sintering temperature and sintering time because of the dense structure due to high temperature and long sintering time. To improve the thermal property, Ag coated micro-SiC particles were used as an alternative to partly replace pure nano-Ag particles. The results demonstrate that the SiC particles can reduce the voids and improve the density of the sintered silver structure. Moreover, the addition of SiC particles can also contribute to the increase of thermal diffusivity. As a result, the thermal conductivity of sintered silver paste with 1.5 wt.% Ag coated SiC particles was two times as compared to that without SiC particles with the same Ag concentration.
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| 2. |
- Wang, Nan, et al.
(författare)
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Highly Thermally Conductive and Light Weight Copper/Graphene Film Laminated composites for Cooling Applications
- 2018
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Ingår i: 2018 19TH INTERNATIONAL CONFERENCE ON ELECTRONIC PACKAGING TECHNOLOGY (ICEPT). - 9781538663868 - 9781538663868 ; , s. 1588-1592
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Konferensbidrag (refereegranskat)abstract
- A light-weight, robust and highly thermal conductive copper/graphene film laminated structure was developed as novel heat spreading materials for thermal management applications. The advantages of the copper/graphene film laminated structure lie in its ability to combine both good mechanical properties of metals and excellent thermal properties of graphene film. Graphene films (GFs) were fabricated via self-assembly of graphene oxide (GO) sheets and post-treated by high temperature graphitization and mechanical pressing. The resulted GFs show excellent flexibility and greatly improved tensile strength which is over 3 times higher than commercial PGS. The successful lamination between copper and GFs was realized by indium bonding. Thin indium layers can provide complete physical contact between copper and GFs, and thereby, minimize the contact resistance induced by surface roughness. The measured contact thermal resistance between copper and GFs bonded by indium is in the range of 2-5 Kmm(2)/W for a working temperature between 20 degrees C to 100 degrees C. This value is orders magnitude lower than other bonding methods, including direct hot pressing of copper and GFs, tape bonding and thermal conductive adhesive (TCA) bonding. By tailoring the thickness of GFs, desirable laminated composites with optimized thermal conductivity can be obtained, which offers an efficient heat dissipation solution for power driven systems.
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| 3. |
- Zhang, Yan, et al.
(författare)
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MDS Investigation on the Melting and Solidification of Silver Nanoparticles
- 2018
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Ingår i: 2018 19th International Conference on Electronic Packaging Technology (ICEPT). - 9781538663868 - 9781538663868 ; , s. 5-9
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Konferensbidrag (refereegranskat)abstract
- Nano-silver pastes have been widely used in electronic packaging because of its outstanding characteristics in the electrical, thermal and mechanical aspects. The sintering process of silver nanoparticles has a great impact on the material features, performances and reliabilities. In the present paper, molecular dynamics (MD) simulations have been carried out, and the melting and solidification process of silver nanoparticles are studied. The phase transformation processes of nanoparticles were analyzed, and various temperature ranges has been considered. The relationship between the temperature and the system energy reflects the melting process, and the atom distributions at characteristic temperature points were observed. The structural development during the sintering of nanoparticles was studied, and there appears the coexistence of different structures in the crystallization.
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