Multi-size nanoparticle hybrid metal film and preparation method thereof

Abstract

The invention provides a multi-size nanoparticle hybrid metal film and a preparation method thereof. The multi-size nanoparticle hybrid metal film comprises an organic medium material which forms an organic coating layer, wherein the organic medium material is configured with nano-metal particles with at least two sizes; the small-size nano-metal particles are driven into gaps of the large-size nano-metal particles by means of physical impact so as to realize gap filling of the large-size nano-copper particles, and the nano-metal particles preferably use a nano-copper material, thereby avoiding the problems such as high porosity, low thermal conductivity, high cost, thermal mismatch with Si, SiC-based chips and high electric mobility of the existing composite silver films, and improving the overall reliability of power devices. Meanwhile, the multi-size nanoparticle hybrid metal film has the characteristic of easy assembly and can effectively reduce the cost.

Description

technical field [0001] The invention relates to the field of chip packaging and interconnection, in particular to a metal film for sintering and its preparation technology. Background technique [0002] In the field of power semiconductor packaging, it is an urgent problem to seek low-temperature technology, high-temperature service, matching thermal expansion coefficient, high thermal conductivity, and low-cost interconnection materials. The traditional material technology of welding and wire bonding has low melting point, high temperature creep failure, wire winding, parasitic parameters and other unsolvable problems. New interconnect materials are developing from welding to sintering technology. By reducing the size of sintered particles and lowering the sintering temperature, nano-metal particle sintering technology has become the most promising technology among new interconnect materials for power semiconductor devices. [0003] At present, the advanced technology repr...

AI Technical Summary

Problems solved by technology

However, the patents, materials, processes and equipment of nano-silver sintering are mainly controlled by foreign manufacturers, and the domestic development is greatly restricted.

At the same time, nano-silver sintering technology also has shortcomings: 1) The price of silver material itself is relatively high, which limits its widespread use

2) The thermal expansion coefficients of silver and SiC chip backside materials are different, and other intermediate metal layers need to be added to improve interconnection performance, thereby increasing process complexity and cost

3) There is electromigration in the silver layer, which is not conducive to the long-term reliable application of power devices

Yet the nano-silver sintered material of multi-layer silver film of the problem of this prior art has many deficiencies: 1) the price of silver material itself is higher, limits it and can not be widely used

2) The thermal expansion coefficients of silver and SiC chip backside materials are different, and other intermediate metal layers need to be added to improve interconnection performance, thereby increasing process complexity and cost

3) There is electromigration in the silver layer, which is not conducive to the long-term reliable application of power devices

However, on the one hand, the materials described in this document are mixed before ink preparation, and there is a risk of agglomeration of nanoparticles during subsequent storage.

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