Luminescent ceramic element for a light emitting device
View Patent ↗A semiconductor structure including a light emitting layer disposed between an n-type region and a p-type region is attached to a compound substrate including a host which provides mechanical support to the device and a ceramic layer including a luminescent material. In some embodiments the compound substrate includes a crystalline seed layer on which the semiconductor structure is grown. The ceramic layer is disposed between the seed layer and the host. In some embodiments, the compound substrate is attached to the semiconductor structure after growth of the structure on a conventional growth substrate. In some embodiments, the compound substrate is spaced apart from the semiconductor structure and does not provide mechanical support to the structure. In some embodiments, the ceramic layer has a thickness less than 500 μm.
1. A method comprising:
providing a compound substrate, the compound substrate comprising:
a host; and
a ceramic layer connected to the host, the ceramic layer containing a luminescent material and having a thickness less than 500 μm; and
attaching a semiconductor structure to the compound substrate, the semiconductor structure including a light emitting layer disposed between an n-type region and a p-type region.
2. The method of claim 1 wherein:
the light emitting layer is configured to emit light of a first peak wavelength when forward biased; and
the luminescent material is capable of absorbing light of the first peak wavelength and emitting light of a second peak wavelength.
3. The method of claim 1 wherein attaching comprises growing the semiconductor structure over the compound substrate.
4. The method of claim 3 wherein:
the compound substrate further comprises a seed layer;
the ceramic layer is disposed between the host and the seed layer; and
growing comprises growing the semiconductor structure directly on the seed layer.
5. The method of claim 1 further comprising growing the semiconductor structure on a growth substrate, wherein attaching comprises bonding the semiconductor structure to the ceramic layer.
6. The method of claim 5 further comprising providing a bonding layer disposed between the semiconductor structure and the ceramic layer.
7. The method of claim 5 further comprising removing the growth substrate after bonding.
8. The method of claim 1 further comprising:
forming a first contact electrically connected to the p-type region; and
forming a second contact electrically connected to the n-type region;
wherein the first and second contacts are both formed on a same side of the semiconductor structure.