Silicon-Ceramic Composite Substrate: A Promising RF Platform for Heterogeneous Integration

The starting point for integrating RF functions in silicon (Si) and low-temperature cofired multilayers with an Si-ceramic (SiCer) composite substrate was the need for cross-sectional construction and connection of both parts from the nanometer to millimeter range. The application of nano and micro effects and structures in microelectromechanical systems (MEMS) requires the fabrication of intelligent and robust connections (electrical, mechanical, fluidic, and thermal) to a manageable carrier system or a printed circuit board. These functions are enabled using SiCer substrates [1]. Crucial back-end processes such as assembly and packaging (mechanical Si bonding or wiring in the ceramic layer) must take place before any micro or nano structuring is performed. Thus, the influence of these processes on sensitive structures (especially on sensitive mechanical systems) can be minimized.