Reflow soldering of fine-pitch devices using a Nd:YAG laser

摘要

Abstract: The drive towards miniaturization in electronics assembly has produced new devices with small lead pitch and high lead count which are difficult to bond reliably to substrates using conventional mass soldering technology. Micro-soldering using lasers has the potential to solve many of the problems involved. The results of Nd:YAG laser soldering trials on a ceramic chip with Kovar leads spaced at 0.025 in. are described. The results are compared with the predictions of a detailed finite-element thermal model of the systems and also with real-time thermocouple measurements of the temperature reached at specific locations during the soldering step. Implications for future work in this area are discussed.!13