Sol–gel matrix for YAG:Ce phosphors in pc-LEDs

Sol–gel formulations were applied to replace silicone as matrix material for phosphors in pc-LEDs. The content of organic groups was minimized in order to reduce yellowing during the operation of the elements. It was possible to evenly embed YAG:Ce particles in sol–gel binders. Further processing on LED chips resulted in operational light sources; and their performance was compared to standard silicone-based elements. Additional deposition of ALD laminates seals possible defects within the sol–gel matrix as additional protection of the phosphors and the underlying LEDs.