Conference Program - LOPE-C 2011

SCIENTIFIC CONF. | THURSDAY-JUNE 30, 2011
Track 5
Sintering of Inorganic Materials (02:30 pm - 04:00 pm) | LOCATION HARMONIE E / LEVEL C2
03:00 pm Conductivity and Adhesion Study of Plasma-sintered Nanoparticle Silver Ink
Mr Juha Niittynen,
Tampere University of Technology, Researcher, Finland
Electronics manufacturing industry is looking for a supplement for the traditional manufacturing technology to meet the new demands of the electronics markets. In recent
years inkjet-printing has been considered as one of the most promising alternatives. The main advantage of inkjet-printing over conventional production technologies is that
it is a completely additive and digitally controlled manufacturing process. Additive processing enables material savings, whereas a digital process control enables easy
product customization and rapid prototyping. However, inkjet-printing has some challenges that need to be resolved before the technology is ready for a large-scale
manufacturing. One of the most serious challenges is the high production cost of inkjet-printing compared to other manufacturing technologies. Amongst the factors causing
high production costs are expensive high-temperature plastic substrates, which are currently needed because of the high sintering temperature of nanoparticle inks.
Low-temperature sintering techniques may lower production costs as they enable the use of cheaper low-temperature plastic substrates.
Plasma sintering is one of the alternatives for low-temperature sintering and it has been used to sinter nanoparticle inks without damaging the thermal-sensitive substrate
material. Test structures were inkjet-printed using a silver nanoparticle ink (Harima) and sintered using a low pressure plasma exposure in order to evaluate the feasibility of
plasma-sintering in the electronics manufacturing. Conductivity and adhesion tests were conducted and were compared to thermally-sintered reference samples.
The study showed that adequate conductivity can be achieved with plasma-sintering. However, the adhesion is inferior to thermally-sintered samples. In this case low
adhesion means that the conductive structures are more susceptible for mechanical damage and, therefore, have a lower reliability, which is an essential factor for today?s
electronics. Therefore, the mechanisms to improve adhesion of plasma-sintering, for example by a surface treatment prior printing, must be investigated in future in order to
use it in large-scale electronics manufacturing.
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