Sintered nanosilver joints on rigid and flexible substrates

Because of new EU laws restricting the use of harmful substances (i.e. Pb because of the RoHS Directive), the search for new methods of joining has become highly urgent. The main problem for most solutions known to date has been to achieve good electrical parameters while maintaining low sintering temperaturatures. Pastes based on silver nanoparticles were developed, which allow to sinter below 300 ^° C. Those layers have sheet resistance below 2 mΩ/sq. Low exposure to heat allows to use these pastes on elastic substrates such as paper or Kapton foil. In present work, the authors proved that it is possible to obtain joints on elastic substrates which can withstand over 30 000 cycles in bend test, with sintering in 300°C, by means of the Low Temperature Joining Technique (LTJT).