LID FOR FUNCTIONAL PART AND PROCESS FOR PRODUCING THE SAME

摘要

A solder layer as a substitute for a high-temperature solder which bonds a functional-part package to a lid and has a solidus temperature of 250°C or higher. It is obtained by: applying a solder paste obtained by mixing a copper-based metal powder having a solidus temperature of 400°C or higher with a tin-based solder powder to a lid made of a material difficult to solder and plated beforehand with a material having excellent solderability; and heating the solder past applied. The solder layer formed on the deposit comprises the copper-based metal powder, an intermetallic compound of Cu₆Sn₅, and the lead-free solder. This solder layer functions as a high-temperature solder because the intermetallic compound is bonded to the material difficult to solder and particles of the intermetallic compound are connected to one another. Although high-temperature solders have poor soldering properties, this problem can be avoided with the solder layer.