Laser device with non-absorbing mirror, and method
A laser device with one or more active regions, such as quantum wells, gain/lighting media, or other devices, and one or more non-absorbing regions, may be formed by a first growth run (growing a first semiconductor layer), then performing selective, shallow-depth etching, and then a second growth run (growing a second semiconductor layer). The laser device may include a first portion, one or more active regions located on the first portion, and a second portion located on the active region(s). A third portion may be located on one or more ends of the first portion and on the second portion. The third portion may be formed during the second growth run, after the etching step. The non-absorbing region(s) may be formed by the third portion and the end(s) of the first portion. If desired, the non-absorbing region(s) may be produced without annealing or locally-induced quantum well intermixing.
1. A laser device comprising:
a first portion made of at least an n-type semiconductor material;
at least one active region located on the first portion; and
an other portion made of at least a p-type semiconductor material, wherein:
the other portion is a single layer,
the other portion comprises at least one non-absorbing region that covers at least one etched end of the at least one active region,
the other portion comprises an inner side and an outer side that opposes the inner side downstream from the inner side in a growth direction that is perpendicular to a direction of laser emission of the laser device, and
the outer side of the other portion comprises at least one first surface and a second surface offset downstream from the at least one first surface in the growth direction.
2. The laser device of claim 1 , wherein:
the laser device further comprises a second portion located on the at least one active region,
the second portion is made of at least a p-type semiconductor material, and
the other portion is a third portion.
3. The laser device of claim 2 , wherein the laser device is an edge-emitting laser device.
4. The laser device of claim 2 , wherein:
the first portion and the third portion define at least one facet, and
the at least one non-absorbing region is located between the at least one etched end and the at least one facet.
5. The laser device of claim 4 , wherein:
the laser device further comprises a substrate, and
the first portion is located on the substrate.
6. The laser device of claim 5 , wherein:
the laser device further comprises a first ohmic contact and a second ohmic contact,
the substrate is located on the second ohmic contact, and
the first portion, the at least one active region, the second portion, and the third portion are located between the first ohmic contact and the second ohmic contact.
7. The laser device of claim 1 , wherein the at least one non-absorbing region has a larger band-gap than the at least one active region such that light generated by the laser device is not absorbed by the at least one non-absorbing region.
8. The laser device of claim 7 , wherein the non-absorbing region has a length in a direction of light emission, and wherein the length of the non-absorbing region is not greater than 500 μm.
9. The laser device of claim 8 , wherein the at least one non-absorbing region comprises a first non-absorbing region at a first end of the laser device and a second non-absorbing region at a second end of the laser device.
10. The laser device of claim 9 , wherein:
the at least one etched end comprises a first etched end and a second etched end,
the first non-absorbing region covers the first etched end, and
the second non-absorbing region covers the second etched end.
11. The laser device of claim 1 , wherein:
the first portion comprises an inner side and an outer side that opposes the inner side downstream from the inner side in the growth direction, and
the outer side of the first portion comprises at least one first surface and a second surface offset downstream from the at least one first surface in the growth direction.
12. The laser device of claim 11 , wherein:
the at least one active region is located on the second surface of the first portion, and
the at least one active region is not located on the at least one first surface of the first portion.
13. The laser device of claim 11 , wherein the first portion is a single layer.
14. The laser device of claim 1 , wherein at least one portion of the inner side of the other portion is upstream in the growth direction from the at least one active region.