Nano conductive adhesive and preparation method thereof

Abstract

The invention provides a nano conductive adhesive. The conductive adhesive is a uniform mixture of one of or two, three or four of micron-grade silver powder, submicron-grade silver powder, nano silver powder or a nano silver wire, and a high molecular material, solvent and a curing agent. The invention also provides a preparation method of the nano conductive adhesive, which comprises the following steps: 1. preparing the micron-grade silver powder, the submicron-grade silver powder, the nano silver powder and the nano silver wire by a microwave method; and 2. mixing the components in different proportions with the high molecular material, the solvent and the curing agent. The invention has the advantages of even diameter of a conductive silver particle obtained by the microwave method and simple preparation. The conductive adhesive performance can be improved by the optimal design of the particle proportion. The conductive adhesive with high conductive performance is prepared by three silver powder particles and one nano silver wire in certain size selection and proportion. The prepared conductive adhesive has stable performance and high rheological property.

Description

technical field [0001] The invention describes a nano-conductive adhesive and a preparation method thereof. The conductive particles are synthesized by a microwave method, and the conductive adhesive with excellent performance is obtained by selecting specific micron to nano-scale silver powder and silver wire particle sizes and proportions. Background technique [0002] The rapid development of electronic technology has put forward higher and higher requirements for the connection of electronic chips and devices. Lead-free use of green electronics has become mainstream in recent years as lead-containing solder paste materials have been banned in Europe and elsewhere. However, lead-free solder paste materials require high-temperature reflow (reflow) at 250-260°C, which consumes a lot of energy; conductive adhesives can be cured at lower temperatures, so they are widely used in many fields, such as conductive bonding of ICs, light-emitting diodes Bonding and heat conduction,...

AI Technical Summary

Problems solved by technology

These techniques have complex reaction conditions, long reaction time (generally need several hours to several days), and shortcomings such as low yield (milligram level)

These technologies are still in the stage of scientific research, so far, there is no technology that can realize the rapid and large-scale preparation of submicron and nano silver particles.

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