Individually Dispersed Nanoparticles formed by Gas Evaporation Method and their Applications

Abstract

Individually dispersed Au, Ag, Cu and ITO nanoparticle ink are formed by using the industrial scale modified gas evaporation method where formed particles are covered with an organic surfactant just after their formation. The average diameters of these particles are less than 10 nm. These nanoparticle inks are called Nanometalink and suitable for ink-jet printing. Ink-jet printing using Nanometalinks are expected to substitute a patterning process using sputtering and photolithography. The inner structures of the cured films are much dependent on curing conditions such as a curing temperature, a temperature profile and a curing atmosphere which affect the resistivities and the mechanical strengths of the films. An Ag Nanometalink film low temperature curing type which is heat treated at 150°C and 180°C, 200°C for 60min with a thickness of 1 μm has a resistivity of 15μΩ·cm, 4 μΩ·cm, and 3μΩ·cm respectively. The adhesion strengths are improved by adding Cu nanoparticles to Ag Nanometalink in the case of high temperature (over 350 C) curing process and by coating resins on a substrate in the case of low temperature curing process.The ITO film which is heat treated at 230°C for 60 min with a thickness of 240 nm has a specific electric resistance of 0.0055Ω·cm and transparency of 95% at 550nm. Other inks properties and application examples are also going to be presented.