Electronic apparatus produced using lead-free bonding material for soldering

Abstract

Disclosed herein is an electronic apparatus produced using a high-temperature lead-free solder alloy which makes it possible to form soldered joints having no variations in strength and which has an excellent balance between strength and solderability. The lead-free solder alloy is an alloy which is made of an element A and an element B and which has a composition composed of AmBn being a stable phase and the element B in an equilibrium state at room temperature. When the lead-free solder alloy is solidified by quenching, the element A is dissolved in a room-temperature stable phase of the element B so that a supersaturated solid solution is formed, and when melted for soldering and then solidified, the alloy returns to its equilibrium state and has a composition composed of the stable phase AmBn and the element B and therefore maintains strength due to the presence of the stable phase AmBn even when reheated to a soldering temperature.

Dependencies are inferred from the claim text.