Panel Level Packaging for LED Lighting

General lighting by use of LED-Chips is one of the strongly growing markets today and also in future. One of the trends goes to LEDs with higher and higher luminous fluxes per chip area to get the best price per lumen on the market. Unfortunately, such large LEDs produce a lot of heat, which must be spread to avoid overheating and shorter lifetime of the LEDs. Another approach is the use of many small LEDs so that both light and heat source are spread into a larger area. Cost-effective established PCB-technology was applied to produce large-area light sources consisting of many small LED chips placed and electrically connected on a PCB-substrate. LEDs were ICA-bonded with their bottom pad to the PCB. The top contacts of the LEDs were established by laminating an adhesive copper sheet followed by a LDI structuring as known from PCB-via-technology. This assembly can then be completed by adding converting and light forming optical elements.