TOKYO – OKI Circuit Technology has developed multilayer PCB technology with stepped copper coin insertion, which reportedly achieves 55 times better heat dissipation than conventional PCBs.

The stepped copper coin is offered in two types, circular and rectangular, to suit the shape of the electronic component mounted on the PCB, and OKI said it is working to develop mass-production technologies with the aim of PCBs with the new technology into markets for compact devices or devices used in outer space or other environments where air cooling technology cannot be used.

In 2015, OTC developed proprietary design and mass production technologies for multi-layer PCBs based on copper coin insertion. This innovation embeds cylindrical copper coins with high thermal conductivity into PCB through-holes and bonds them to heat-generating electronic components to dissipate heat to the underside of the substrate. The use of copper coins that transfer heat to the underside of the PCB achieves high heat dissipation efficiency in cases where it is not possible to mount heat-dissipating devices directly to electronic components due to dimensional constraints of the device or where heat-dissipating devices cannot be mounted to certain functional surfaces (e.g., image sensors or light-emitting components). This time, OKC said it has made further progress with this technology and succeeded in developing the stepped copper coin that achieves approximately twice the heat dissipation efficiency.

The newly developed stepped copper coin features a larger heat-dissipating area relative to the bonding surface with the heat-generating electronic component to improve heat conduction efficiency. Additionally, aiming for an optimal heat dissipation structure to suit the shape of each electronic component, a rectangular type featuring a rectangular component installation surface and rectangular heat-dissipating surface has been developed, in addition to the conventional circular type, to increase the contact area and heat-dissipating area for rectangular electronic components to improve heat dissipation efficiency. Both types can be customized to obtain an optimal heat dissipation structure for the given shapes of the mounted component and the PCB itself and the substrate thickness.