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
03:20 pm Inkjet printing and microwave flash sintering of conductive nanoparticles for R2R applications
Dr Jolke Perelaer,
Friedrich-Schiller-University Jena, Postdoc / project manager, Germany
In recent years, inkjet printing is increasingly used as a flexible and digital patterning technique in the field of microelectronics. The main advantages of inkjet printing are its
ease of processing and its potential for mass production. Furthermore, based on its digital properties, inkjet printing is both a flexible and low cost technique, since materials
are used in an efficient manner, compared to other patterning techniques, like non-digital printing techniques and spin coating, which significantly reduces waste production.
During the last years, there has been a growing interest in printing silver inks as a basis for conductive tracks in microelectronics applications, including OLED, OPV and
RFID.
Currently, much interest is dedicated to inkjet printing of conductive materials, such as silver nanoparticles; as an effect of their reduced particle size, the melting
temperature is reduced significantly. Although the sintering temperatures are reduced to well below 300 °C, these temperatures are not compatible with polymer foils, which
are required for applications in plastic electronics.
We have used alternative techniques to sinter inkjet printed silver nanoparticles that are compatible with common polymer foils, such as PET and polycarbonate. The
process involves either a low pressure argon plasma exposure or microwave radiation.
Recently, we made good progress with combining the two alternative techniques, which enhances the process of creating conductive patterns on polymer substrates in two
ways: firstly, the features' conductivity can be increased by using a hybrid sintering setup and, secondly, the overall sintering time can be reduced by using the so-called
flash sintering approach. Hereby, sintering times can be reduced from more than one hour to a few minutes or even seconds. Furthermore, the obtained conductivity is
between 10 and 50% of bulk silver, while leaving the polymer substrate unaffected.
These conductive features may be used in many plastic electronic applications.
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