Influences of Heat Treatment on Microstructures and Electrical Properties of Core-Shell Copper-Silver Composite Material

論文翻譯標題: 熱處理對核殼結構銅銀複合材料之微結構與電性之影響
  • 余 義傑

學生論文: Master's Thesis


In technology of manufacturing the electrically conductive paste the electrically conductive metallic powder is the key For the electrically conductive paste in addition to gold and silver powder that is often applied as the electrically conductive powder other metallic powder with lower price like copper nickel or aluminum powder play a secondary role Among those metals silver is applied most extensively In recent years since the price of the precious metals soars the cost of the electrically conductive pastes raises as well Therefore it has become a trend to replace the electrical paste made of the precious metals by the low-cost electrically conductive metallic powder in the future This paper discussed one of the low-cost replaceable material core-shell silver-copper composite material or core-shell copper-silver study the influences of heat treatment on its sintering behavior and electrical properties The core-shell copper-silver powder to be discussed in this paper is prepared by using Gal Tiffany displacement reaction The prepared powder is then make into pastes and sintering by different temperature and atmosphere The sintered pastes then be analyzed in order to obtain its optimal sintering condition and lowest resistivity This research divided into two main parts which included low and high temperature sintering For low temperature sintering the temperature is set at range from 250℃ to 550℃ with interval 50℃ And for high temperature sintering the studied temperature range is from 600℃ to 800℃ with interval of 100℃ in order to study the sintering behavior microstructure electrical properties and thermal characteristic By experiment and analysis the melting temperature of nanoscale silver particles is obtained to be around 150℃(2 5?m) and 118°C(1 5?m) The nanoscale silver melted and form a reticular to hold the copper particles In low temperature sintering system the optimal sintering temperature is dropped at 350℃ for 2 5?m AgCu and 250°C for 1 5?m AgCu which gives the lowest resistivity of 2 11×10-5 Ω cm (2 5?m) and 6 95×10-5 Ω cm (1 5?m) By microstructure analysis the core copper of 2 5?m AgCu is found out to start oxidize at around 250℃ and follow by the increased of temperature the oxidize become worse and worse At around 350℃ the sintered paste appeared with best densification When the sintering temperature reached 550℃ almost all the copper particles are oxidized For 1 5?m AgCu the core copper was fully oxidized at 350°C In high temperature sintering system the lowest resistivity is 9 93×10-7 Ω cm which sintered under nitrogen atmosphere
獎項日期2016 八月 24
監督員Wen-Shi Lee (Supervisor)