Copper Materials for Low Temperature Sintering
Masamu Nishimoto, Rintaro Tokura, Mai Thanh Nguyen, Tetsu Yonezawa
Abstract
In this review paper, recent studies on low-temperature sintering strategies of copper materials for conductive layer preparation have been summarized. Coinage metals, gold, silver, and copper have been used as materials for conductive inks and pastes for printed electronics. Copper is a highly electrically and thermally conductive material that can be used in electronic circuits and die-attach materials. Recently, copper-based inks/pastes have gained significant attention of researchers and industries as conductive materials. However, copper is readily oxidized under air, especially, at the nanoscale, and copper particles may catch fire because of the rapid oxidization. To overcome this issue, copper nanoparticles and fine particles are coated with organic molecules which act as insulators after sintering. Some interesting surface treatments or activation strategies have been investigated in this regard. In this paper, different perspectives on the applications of copper in conductive and die-attach materials have been presented.