New Vias in DBC

Citation

(2000), "New Vias in DBC", Microelectronics International, Vol. 17 No. 3. https://doi.org/10.1108/mi.2000.21817cad.003

New Vias in DBC

New Vias in DBC

Keywords Curamik Electronics, Vias, Copper

Curamik Electronics GmbH has developed a new technology which creates solid copper vias in substrates for power electronics applications. This offers high reliability and very high current carrying capability. The solid copper vias make multilayer power substrates possible at reasonable prices.

Using the Direct Copper Bonding process on both sides, two copper foils (0.2mm-0.3mm thick) are eutectically connected with the ceramic (Al₂O₃ or AlN) carrier. The first copper foil is then welded to the second copper foil through a hole in the ceramic.

One advantage of this new technology is the possibility of using thin (for example 0.38mm) ceramics. Quality and manufacturing efficiency are improved significantly compared to traditional techniques. The solid copper vias also meet the temperature cycling conditions required for the automotive and defence industries. The current carrying capability of solid copper vias at 0.63mm ceramic thickness can be up to 100A of continuous current. The measured hermeticity of the via is better than 10^–9 at m x cm³ x sec^–1. Electrical resistance is as low as 50 MicroOhms per via.

These specifications make this technology a preferred solution for the production of lightweight hermetic packages. It is also ideal for substrates that require front-to-back grounding such as DC/DC converters or using the backplane for high current connections.

The base material of these DBC substrates is Al₂O₃ for medium and high power and AlN for very high power applications. A variety of surface platings are available. Nickel, or Nickel and Gold, can be plated on to the copper. Both of them have excellent soldering and wire-bonding characteristics. Solder stop can also be printed onto the substrate for positioning chips or other components. As the bonding technology of these substrates is a high temperature process, the application temperature of these substrates can exceed 500°C.

For further information, please contact: Curamik Electronics. Tel: +49 (0) 9645 9222501/ (0) 9645 922222.