Method of processing a semiconductor structure
View Patent ↗A method according to embodiments of the invention includes providing a wafer including a semiconductor structure grown on a growth substrate, the semiconductor structure comprising a III-nitride light emitting layer sandwiched between an n-type region and a p-type region. The wafer is bonded to a second substrate. The growth substrate is removed. After bonding the wafer to the second substrate, the wafer is processed into multiple light emitting devices.
1. A method comprising:
providing a wafer comprising a semiconductor structure grown on a growth substrate, the semiconductor structure comprising a III-nitride light emitting layer sandwiched between an n-type region and a p-type region;
bonding the wafer to a transparent substrate that comprises a wavelength converting material disposed in glass;
removing the growth substrate;
after bonding the wafer to the transparent substrate, processing the wafer into multiple light emitting devices;
testing the wafer after processing the wafer into multiple light emitting devices and before dicing the wafer; and
adjusting an amount of wavelength converting material corresponding to each light emitting device according to the results of the testing.
2. The method of claim 1 wherein adjusting comprises removing wavelength converting material by laser ablation.
3. The method of claim 1 wherein adjusting comprises adding wavelength converting material.
4. The method of claim 1 wherein bonding the wafer to a second substrate comprises pressing the wafer and the second substrate together at a temperature greater than 500° C.
5. The method of claim 1 wherein processing the wafer into multiple light emitting devices comprises:
forming a metal contact on the p-type region;
removing a portion of the light emitting layer and the p-type region to reveal a portion of the n-type region; and
forming a metal contact on the n-type region exposed by removing a portion of the light emitting layer and the p-type region.
6. The method of claim 1 wherein processing the wafer into multiple light emitting devices comprises dicing the wafer into single light emitting diodes or groups of light emitting diodes.
7. A method comprising:
providing a wafer comprising a semiconductor structure grown on a growth substrate, the semiconductor structure comprising a III-nitride light emitting layer sandwiched between an n-type region and a p-type region;
bonding, using a bonding material, the wafer to a transparent substrate that comprises a wavelength converting material disposed in glass;
removing the growth substrate; and
after bonding the wafer to the second substrate, processing the wafer into multiple light emitting devices.
8. The method of claim 1 further comprising forming an optical impedance matching layer on the semiconductor structure prior to bonding.
9. The method of claim 1 further comprising texturing a surface of the second substrate opposite a surface bonded to the semiconductor structure.
10. The method of claim 1 wherein processing the wafer into multiple light emitting devices occurs after removing the growth substrate.
11. The method of claim 1 further comprising bonding the wafer to a handle before removing the growth substrate, wherein bonding the wafer to a second substrate occurs after removing the growth substrate while the semiconductor structure is bonded to the handle.
12. The method of claim 1 further comprising forming a reflective contact on a surface of the semiconductor structure opposite a surface bonded to the second substrate.