Substrate materials

Selecting the right substrate plays a central role in the functionality and reliability of the assembled component. Ceramic substrates have thermal conductivity that is magnitudes higher than that of conventional PCB material (FRx).

The electrical circuit layout can be created on these substrates with minimum influence from parasitic stray capacitance directly by means of multi-layer thick-film technology. Through-connections (Vias) permit two-sided circuit layouts. In addition, ceramic circuit carriers are optimally adapted to standard semiconductor systems thanks to their low coefficient of thermal expansion (CTE) compared with conventional FRx printed circuit boards.

This permits the use of unhoused chips (bare dies) in Chip-on-Board (COB) Technology for applications in harsh environments where very high demands are placed on the reliability of the substrate-semiconductor connection. In addition, for the creation of electronic assemblies, direct-copper-bond (DCB) substrates with high current carrying capacity as well as insulate metal substrates (IMS) for optimum distribution of the heat loss are available for power electronics assemblies. The substrates are typically linked to a heatsink so that the electrical losses can be distributed efficiently. In addition to traditional metal alloys such as CuMo, thermally adapted alternatives made of composite materials such as Al-SiC and AlG can be used here. These bring with them a considerable weight saving.

Power LED module on IMS substrate for efficient discharge of heat loss

Frequency converter in stacked circuit configuration for engine drive control