Algainn-based lasers produced using etched facet technology
View Patent ↗A process for fabricating AlGaInN-based photonic devices, such as lasers, capable of emitting blue light employs etching to form device waveguides and mirrors, preferably using a temperature of over 500° C. and an ion beam in excess of 500 V in CAIBE.
1. A method for fabricating a photonic device, comprising the steps of:
epitaxially depositing an AlGaInN-based structure on a substrate; and
dry etching at least one facet in said AlGaInN-based structure, wherein said substrate is heated to over 500° C. during said dry etching step.
2. The method of claim 1 , wherein said photonic device is a laser.
3. The method of claim 1 , further comprising using a patterned high-temperature-stable mask during said dry etching step to define said at least one facet.
4. The method of claim 1 , wherein said structure has a p-doped cap layer at its top surface, and said method further comprises forming a mask on said p-doped cap layer that maintains the conductivity of said cap layer.
5. The method of claim 1 , wherein said substrate is heated below 700° C. during said dry etching step.
6. A method for fabricating lasers, comprising the steps of:
epitaxially depositing an AlGaInN-based structure on a substrate;
dry etching said AlGaInN-based structure to fabricate therein a multiplicity of lasers with etched facets, said dry etching being performed with said substrate at a temperature above 500° C.;
forming electrical contacts for the lasers;
testing the lasers on the substrate; and
thereafter singulating the substrate to separate the lasers for packaging.
7. The method of claim 6 , wherein said dry etching step is carried out using ion beams with an ion beam voltage in excess of 500V.
8. The method of claim 7 , wherein said substrate is at an angle other than perpendicular to said ion beam during said dry etching step.
9. A method for fabricating a photonic device, comprising the steps of:
epitaxially depositing an AlGaInN-based structure on a substrate; and
dry etching at least one facet in said AlGaInN-based structure, wherein said dry etching step is carried out using ion beams with an ion beam voltage in excess of 500V.
10. The method claim 9 , where said photonic device is a laser.
11. The method of claim 9 , further comprising placing said substrate at an angle other than perpendicular to said ion beam during said dry etching step.
12. The method of claim 9 , wherein said ion beam is formed from Xe ions.
13. The method claim 9 , further comprising maintaining said substrate at a temperature over 500° C. during said dry etching step.
14. The method claim 10 , further comprising maintaining said substrate at a temperature over 500° C. during said dry etching step.
15. The method claim 11 , further comprising maintaining said substrate at a temperature over 500° C. during said dry etching steps.
16. A method for fabricating a laser, comprising the steps of:
epitaxially depositing an AlGaInN-based structure on a substrate;
forming a front facet of said in said AlGaInN-based structure in a first dry etching step, wherein said first dry etching step is carried out using ion beams with an ion beam voltage in excess of 500V and said substrate is positioned at an angle other than perpendicular to the ion beams;
forming a back facet of said laser in a second dry etching step; and
forming a ridge between said front and back facets in a third dry etching step, said front facet being formed at and extending across a first end of said AlGaInN-based structure and said ridge in a single plane at or around 90-degrees to said substrate.
17. The method of claim 16 , wherein said second and third dry etching steps are carried out using ion beams in excess of 500V.
18. The method of claim 16 , wherein said first, second, and third dry etching steps are performed with said substrate at a temperature over 500° C.
19. The method of claim 18 , wherein said second and third dry etching steps are carried out using ion beams in excess of 500V.
20. The method of claim 19 , wherein said substrate is positioned at angle other than perpendicular to the ion beam during the second dry etching step.