Edge-emitting semiconductor laser diode and method for producing the same

1. An edge emitting semiconductor laser diode comprising:

an epitaxial semiconductor layer stack having a main body and a ridge waveguide, wherein the main body has an active layer configured to generate electromagnetic radiation; and

a planarization layer, wherein the planarization layer embeds the ridge waveguide in such a way that a surface of the ridge waveguide and a surface of the planarization layer form a planar main face, wherein the planarization layer has a plurality of regions arranged one above another, and wherein the region of the planarization layer that adjoins the semiconductor layer stack contains a dopant.

2. The semiconductor laser diode according to claim 1 , wherein the planarization layer contains an absorber material.

3. The semiconductor laser diode according to claim 1 , further comprising a passivation layer arranged between the planarization layer and the semiconductor layer stack.

4. The semiconductor laser diode according to claim 1 , wherein the surface of the ridge waveguide is free of the planarization layer.

5. The semiconductor laser diode according to claim 4 , further comprising an electrical connection layer is arranged on the main face.

6. The semiconductor laser diode according to claim 1 , wherein the planarization layer comprises a glass.

7. The semiconductor laser diode according to claim 1 , wherein the planarization layer comprises a glass selected from the group consisting of spin-on glass, borosilicate glass, phosphosilicate glass or a float glass.

8. The semiconductor laser diode according to claim 1 , wherein

semiconductor layers of the semiconductor layer stack are arranged in a manner spaced apart laterally on both sides alongside the ridge waveguide, the semiconductor layers being delimited by trenches; and

the planarization layer is arranged in the trenches.

9. The semiconductor laser diode according to claim 8 , wherein the trenches are embodied in a V-shaped fashion and the semiconductor laser diode is a high-power laser.

10. A method for producing an edge emitting semiconductor laser diode, the method comprising:

providing a semiconductor layer stack;

etching the semiconductor layer stack in such a way that a main body and a ridge waveguide are formed;

applying a planarization layer in such a way that the ridge waveguide is embedded in the planarization layer, wherein a dopant is dissolved in the planarization layer;

after applying the planarization layer, carrying out a heat treatment method in such a way that the dopant diffuses in the direction of an interface between the planarization layer and the semiconductor layer stack;

exposing a surface of the ridge waveguide in such a way that a surface of the ridge waveguide and a surface of the planarization layer form a planar main face; and

arranging an electrical connection layer on the main face.

11. The method according to claim 10 , wherein the planarization layer is applied by a spin-on process of a liquid suspension.

12. The method according to claim 10 , wherein the exposing is carried out by a whole-area dry- or wet-chemical etching-back process or a chemical mechanical polishing process.

13. The method according to claim 10 , further comprising, before applying the planarization layer, applying a passivation layer or an etching stop layer to the semiconductor layer stack.

14. The method according to claim 10 , wherein the refractive index of the planarization layer is set by a heat treatment method.

15. The method according to claim 10 , wherein providing the semiconductor layer stack comprises providing an epitaxial layer stack.

16. The method according to claim 10 , wherein the main body having an active layer configured to generate electromagnetic radiation.

17. An edge emitting semiconductor laser diode comprising:

an epitaxial semiconductor layer stack having a main body and a ridge waveguide, wherein the main body has an active layer configured to generate electromagnetic radiation, wherein semiconductor layers of the semiconductor layer stack are arranged in a manner spaced apart laterally on both sides alongside the ridge waveguide, the semiconductor layers being delimited by trenches; and

a planarization layer, wherein the planarization layer embeds the ridge waveguide in such a way that a surface of the ridge waveguide and a surface of the planarization layer form a planar main face, wherein the planarization layer is arranged in the trenches.

18. The semiconductor laser diode according to claim 17 , wherein the trenches are embodied in a V-shaped fashion.

19. The semiconductor laser diode according to claim 17 , wherein the semiconductor laser diode is a high-power laser.