Abstract
Monitoring of the quality of soldered joint is researched and developed by detecting the voltage between copper alloy lead and thick film on the substrate in micro reflow soldering process with heated tip with controlled current.
Quality of soldered joint, which is composed with copper alloy lead (Cu-Sn) and thick film (Ag/Pd or Ag/Pt: thickness 10 μm) on alumina substrate or porceline substrate, is mainly influenced by the temperature at soldered part, heating time in micro-soldering process and tip force. Furthermore, the quality of joint confirmes by being approximately estimated soldered area by tensile shear testing or peel testing.
The quality of soldered joint is shown experimentally to be estimated to some extent by the measurement the effective integral of the voltage between copper alloy lead and thick film on the substrate in micro-soldering process.
