Nanoparticle interconnecting material with core-shell structure and preparation method thereof

Abstract

The invention provides a preparation method of a nanoparticle interconnecting material with a core-shell structure. The preparation method of the nanoparticle interconnecting material with the core-shell structure comprises the steps of (A) mixing nano-copper particles and a protection agent, and obtaining a nano-copper solution; (B) mixing a shell layer precursor and the nano-copper solution, reacting, and centrifugally washing to obtain core-shell dual-metal nanoparticles; and (C) dispersing the core-shell dual-metal nanoparticles into a solvent, and defoaming to obtain the nanoparticle interconnecting material with the core-shell structure. The shell layer prepared through the invention is compact in metal form, uniform and controllable in size, and easy to generate atomic diffusion ata lower temperature, and is connected with the nano-copper particles to form a three-dimensional interconnecting system, so that not only are the inoxidizability and the stability of the core layer nano-copper particles improved, but also an interconnecting temperature and an interconnecting condition are greatly reduced. A chip and a substrate can be interconnected under a low-temperature non-pressure condition, and a semiconductor device is connected and packaged, so that the nanoparticle interconnecting material with the core-shell structure can be better applied to the fields of semiconductor device manufacturing and microelectronic packaging, power electronics packaging and the like.

Description

technical field [0001] The invention relates to the technical field of electronic packaging, in particular to a nanoparticle interconnect material with a core-shell structure and a preparation method thereof. Background technique [0002] In recent years, microelectronic systems have developed towards high power, high-density integration, miniaturization, and multi-functionalization, which put forward higher requirements for the performance and thermal management of electronic packaging and interconnection materials, such as realizing high temperature resistance and interconnection. Connecting (greater than 200°C) or multi-level packaging requires pre-level interconnection with low temperature connection and high temperature resistance, etc. High interconnection temperature has a great negative impact on the reliability of microelectronic products. [0003] At present, the interconnection materials used in the field of microelectronic packaging are mainly alloy solder paste ...

AI Technical Summary

Problems solved by technology

Both nano-silver and nano-copper have high electrical and thermal conductivity, and low interconnection welding temperature, but silver is a noble metal, the material cost is expensive, and there are problems of electromigration and particle migration

Although the cost of nano-copper is low, it has the defect that it is easy to be oxidized, especially for some conductive copper pastes that need to be sintered at low temperature. The oxidation of copper will increase the melting point and cause sintering failure. Therefore, a protective atmosphere is often required during the sintering process. It is dangerous and the process is more complicated

Or use a protective agent such as PVP to protect the nano-copper from oxidation, but this has a great impact on the conductivity of the sintered material