A new type of white LED light source by bonding fluorescent SiC and a near-UV LED

Fluorescent silicon carbide (f-SiC) has advantages over phosphors in terms of abundancy, long lifespan, good thermal conductivity and high color rendering index [1, 2]. In this paper, we demonstrate a prototype of fluorescent SiC hybridly integrated with a near UV LED. The fabrication and characterization of the prototype are introduced and the future perspectives are foreseen.

The bonding process of an NUV LED and a B-N co-doped f-SiC epi-layer is shown in Fig.1. HSQ layers are spun on both the 4H-SiC substrate of the NUV LED and the polished backside of the free-standing f-SiC epi-layer. Afterwards, the NUV LED and the f-SiC epi-layer are placed with the surfaces covered by the HSQ layers in contact.

During bonding at 400 °C, HSQ is converted into solid SiOx and by doing so the two samples are bonded together.