Advanced Glass Interposer with Carbon Copper Composite Metallization (GINCO)

The Main goal is optimizing heat transfer of MEMS or SMD components on PCB substrates. Hahn Schickard will investigate some novel carbon-copper-layers on glass interposers and a new architecture of vias, i.e. electrically and thermally conductive contacts between front and back side of glass.

Modern circuit boards include IC chips, i.e. integrated curcuits, and in special applications some additional substrates, i.e. interposers, carrying a group of IC’s like memories, processors or sensors. These interposers realize the electrical connections and the heat transfer going outside. Several IC components generate a lot of heat; so the design of their interposer substrates, based on monocristalline silicon, is complicated and expensive. The GINCO project will develop, realize and characterize a new type of glass interposers, based on carbon-copper conductive layers. As carbon, nano structures like graphene are preferred, which will significantly rise the thermal conductivity and conserve the electrical one. Compared to the state of the art, the project will explore:

• The design of the new carbon-copper-composite material, reducing costs and rising the thermal conductivity.
• Design of vias, i.e. metallic contacts going through the glass from front to back side; TGV („through glass vias“).

The project consortium, including Fraunhofer-IKTS in Dresden, Hahn-Schickard and the Białystok University of Technology, and supported by several companies, has to apply MEMS technologies and the packaging of PCB substrates. Hahn-Schickard is designing vias, which will be laser drilled by a company. Then, the vias will be filled with solder metals. The interposer surface will be sputtered by copper with an additional carbon layer, realized by Białystof University. The result will be electrically and thermally conductive and charcterized at FhG-IKTS. An additional laser structuring step will separate and isolate the electrical contacts. At least, heat sources and heat sinks are added to the substrate; and it is necessary to realize a PCB substrate having some suitable redistribution layers, in order to characterize the real construction of curcuit boards.