▎ 摘　　要

NOVELTY - A high-thermal-conductivity nano-sintered silver paste comprises 55-65 parts mass silver powder, 0.5-10 parts mass graphene oxide, 45-65 parts mass epoxy resin, 5-20 parts mass activator, 1-3 parts mass initiator and 5-15 parts mass organic solvent. The graphene oxide is modified before the preparation of the high-thermal-conductivity nano-sintered silver paste. The modification method involves mixing and stirring carbon powder, nano titanium dioxide and cyanate ester resin to obtain modified cyanate ester resin, mixing with graphene oxide, carrying out electron radiation treatment, and drying. USE - High-thermal-conductivity nano-sintered silver paste used as interface material for high-speed computer chips, power semiconductor devices and high-brightness LEDs. ADVANTAGE - The nano-sintered silver paste has excellent electrical conductivity, thermal conductivity and stability by activating the silver powder, and mixing and stirring with graphene oxide and epoxy resin. The preparation method is simple and economical, reduces the silver paste sintering temperature, and improves the compatibility between the graphene material and epoxy resin, so that the graphene material exerts the excellent electric conducting and heat conducting performance. The silver powder is activated using activator, so that a trace oxide layer on the silver powder surface is removed, and prevents from oxidation and agglomeration, thus increasing the conductivity of the silver paste. DETAILED DESCRIPTION - An INDEPENDENT CLAIM is included for preparation of high-thermal-conductivity nano-sintered silver paste, which involves (s1) activating the silver powder using the activator, (s2) mixing the activated silver powder with the modified graphene oxide, and ball-milling to obtain mixed powder, (s3) adding the epoxy resin, initiator and organic solvent into the mixed powder, stirring, and dispersing the stirred mixture to obtain dispersed silver paste, and (s4) defoaming the dispersed silver paste at room temperature for 5 minutes in vacuum.