ZINC NANOPARTICLES HAVING LOW MELTING POINT, AND PREPARATION METHOD THEREOF

摘要

The present invention relates to nanoparticles having a size of 1-20 nm prepared by the electrolysis of zinc, and a preparation method thereof. The nanoparticles are surface melted at 111-130 ℃. A solder ball comprising the nanoparticles can be sintered at a temperature of 180 ℃ or lower, thereby providing the following advantages: First, since the heating temperature can be lowered from 240 ℃ to 180 ℃ in the case of a reflow process, a conventional reflow apparatus consuming 74 kW can be operated with 56 kW, thereby leading to a reduction in energy by 24%. Second, since the deformation of a PCB is minimized by lowering the temperature of a reflow process and a cheap polymer material such as PET having a low glass transition temperature can be used, it is possible to create the field to which a mounting material having a low unit cost is applied. Third, if using nanoparticles having a size of 10 nm or less, the uniformity of a solder paste on a pad can be increased, and the limit of micro-patterning in a nano-solder ink can be overcome due to the small size of particles (figure 4).