Aerosol Printing of High Resolution Films for LTCC-Multilayer Components

Abstract

For the electronic packaging of sensor stable and cost-efficient fine-line printing technologies on LTCC and high frequency laminates are needed. Especially common technologies like screen printing and thin film techniques are unsuitable for fine structures or too expensive. In addition there is no direct write technology for 3D-LTCC-designs as well as for high reliability Co-firing structures. Closing this gap the aerosol printing technology is used to print high resolution conductors on planar and non-planar substrates. Aerosol printing is a direct write non-contact printing technology of functional layers. After a pneumatic atomization the ink is transformed into 1 to 5 μm droplets. The resulting, continuous aerosol stream is focused by a sheath gas in the printing head. Thus the long standoff distance between substrate and deposition tip of max. 5 mm allows the 3D-printing on non-planar substrates. With optimized inks and printing parameters line widths of 10 μm are achievable. This paper will present applications for aerosol printed functional layers on LTCC. These are, for example, aerosol printed films embedded in co-fired LTCC, fine line structures for high frequency applications and the evaluation of printed 3D-structures like LTCC-stairways. Furthermore the 90 degree contacting of unconventional sensor designs will be presented.