Coin Electronics

A new approach

For the first time, a highly manufacturable integration strategy has been developed for making 3D flexible sensor arrays and connecting them to control electronics based on the widely popular phrase, “Two sides of the same coin”.

The key innovation in this work is the fabrication of through polymer vias (TPVs) for interconnecting sensors made on one side of a polymer thin film to the control electronics fabricated on the other side. All the of fabrication, including the sensor array, TPVs and control electronics can be done on the same substrate using CMOS compatible processes. Hence, the technology is applicable to any sensor array and any thin film transistor (TFT) including silicon, silicon germanium, gallium nitride, etc. based electronics.

“Two sides of the same coin -> Electronics”

The polymer used in the process is polyimide, which is a mechanically stable, chemically inert and environmentally friendly polymer. The sensors are fabricated on one side of the polymer thin film, while the electronics are on the other side. TPVs are basically interconnections made through this polymer layer (hence the name through polymer vias). The interconnections are made using copper which is a low-cost metal commonly used in the electronics industry. This method reduces the overall area of the electronic device, increases the contact between the sensor layer and the sensed surface, and increases the distance between the control electronics and the sensed surface.

So where to from here then?

This is an important advantage in case of biomedical applications because the sensed surface, which can be the skin or the brain surface, remains free of the heat dissipated by the control electronics.

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