Semiconductor laser diode and method for manufacturing a semiconductor laser diode
A semiconductor laser diode and a method for manufacturing a semiconductor laser diode are disclosed. In an embodiment a semiconductor laser diode includes an epitaxially produced semiconductor layer sequence comprising at least one active layer and a gallium-containing passivation layer on at least one surface region of the semiconductor layer sequence.
1. A semiconductor laser diode comprising:
an epitaxially produced semiconductor layer sequence comprising at least one active layer; and
a gallium-containing passivation layer on at least one surface region of the semiconductor layer sequence,
wherein the passivation layer comprises at least one layer with AlGaN, and
wherein a composition of the AlGaN varies over a thickness of the passivation layer.
2. The semiconductor laser diode according to claim 1 , wherein the passivation layer comprises a layer stack with at least one layer with GaN and at least one layer with AlN.
3. The semiconductor laser diode according to claim 1 , wherein the passivation layer comprises at least two layers with the same material having different thicknesses.
4. The semiconductor laser diode according to claim 1 , wherein the semiconductor layer sequence has a ridge waveguide structure with a ridge having ridge side surfaces, and wherein the surface region comprises at least one ridge side surface.
5. The semiconductor laser diode according to claim 4 , wherein the passivation layer at least partially planarizes the ridge waveguide structure.
6. The semiconductor laser diode according to claim 4 , wherein the passivation layer comprises at least a first layer formed laterally beside the ridge waveguide structure and spaced apart from the ridge waveguide structure, and wherein the first layer, a trench between the first layer and the ridge waveguide structure, and a side surface of the ridge waveguide structure is covered with a second layer.
7. The semiconductor laser diode according to claim 1 , wherein the passivation layer has a varying layer composition and/or a varying material composition along an emission direction of the semiconductor laser diode.
8. The semiconductor laser diode according to claim 1 , wherein the passivation layer is transparent and electrically insulating.
9. The semiconductor laser diode according to claim 1 , wherein the passivation layer has a lower crystallinity than all semiconductor layers of the semiconductor layer sequence.
10. The semiconductor laser diode according to claim 1 , wherein the passivation layer has a partially crystalline or amorphous crystal structure.
11. The semiconductor laser diode according to claim 1 , wherein the passivation layer and the semiconductor layer sequence comprise materials selected from the same III-V compound semiconductor material system.
12. The semiconductor laser diode according to claim 1 , wherein the passivation layer comprises a nitride.
13. The semiconductor laser diode according to claim 1 , wherein the passivation layer comprises at least one layer with GaN.
14. The semiconductor laser diode according to claim 1 , wherein the passivation layer comprises at least one layer with AlN.
15. The semiconductor laser diode according to claim 1 , further comprising an electrode layer arranged on the passivation layer.
16. The semiconductor laser diode according to claim 15 , wherein the passivation layer has a layer comprising GaN or AlGaN adjacent to the electrode layer.
17. A method for manufacturing the semiconductor laser diode according to claim 1 , the method comprising:
providing the semiconductor layer sequence; and
depositing the gallium-containing passivation layer on the at least one surface region of the semiconductor layer sequence by an atomic layer deposition.
18. A semiconductor laser diode comprising:
an epitaxially produced semiconductor layer sequence comprising at least one active layer; and
a gallium-containing passivation layer disposed on at least one surface region of the semiconductor layer sequence,
wherein the passivation layer has a lower crystallinity than all semiconductor layers of the semiconductor layer sequence.
19. A semiconductor laser diode comprising:
an epitaxially produced semiconductor layer sequence comprising at least one active layer; and
a gallium-containing passivation layer on at least one surface region of the semiconductor layer sequence,
wherein the passivation layer has a partial crystalline structure or amorphous crystal structure.
20. The semiconductor laser diode according to claim 19 , wherein the passivation layer is transparent and electrically insulating.
21. The semiconductor laser diode according to claim 19 , further comprising an electrode layer arranged on the passivation layer.