Solder powder, method for making the solder powder and solder paste using the solder powder

摘要

According to the present invention, the oxidation of the surface of solder particles is inhibited and the generation of solder balls in the reflow soldering process is inhibited. More specifically, the present invention protects the surface of the solder particles from oxidation during all steps, including the storage of a solder powder, formation of a paste from the solder powder, printing, transferring to a reflow oven and reflow soldering, to minimize the oxidation of the solder particles at these steps so that the generation of solder balls is minimized. In addition, the present invention provides a method for making the solder powder and a solder paste using the solder powder. The objective of the present invention is achieved by the solder powder, the particles of which have on the surface thereof an organometallic compound composed of adipic acid and a metal of the solder alloy. This solder powder is produced by reacting particles of the solder alloy powder with vaporized adipic acid. According to the present invention, the solder powder, the particles of which have on the surface thereof an adipic acid-derived organometallic compound combined chemically with the surface of the solder particles, is blended with a flux to be made into a paste.