Optoelectronic semiconductor body having a layer stack, arrangement of a plurality of optoelectronic semiconductor bodies having a layer stack, and method for producing said optoelectronic semiconductor body
An optoelectronic semiconductor body is provided with a layer stack with an active region which is configured to emit electromagnetic radiation and which includes a main extension plane, wherein the layer stack comprises side walls which extend transversely to the main extension plane of the active region, and the side walls are covered at least in places with a cover layer which is formed with at least one semiconductor material. In addition, an arrangement of a plurality of optoelectronic semiconductor bodies and a method for producing an optoelectronic semiconductor body are provided.
1. An optoelectronic semiconductor body, comprising:
a layer stack with:
an active region, which is configured to emit electromagnetic radiation and which comprises a main extension plane, wherein p 1 the layer stack comprises a hexagonal shape in a plane parallel to the main extension plane of the active region,
the layer stack comprises a p-doped region and an n-doped region, wherein the active region is arranged in the stack direction between the p-doped region and the n-doped region,
the p-doped region and the n-doped region each have sidewalls that face each other and overlap in a plane that is perpendicular to the main extension plane of the active region,
a mask layer comprising a dielectric material is arranged on an upper surface of the layer stack, the layer stack is undercut under the mask layer,
the layer stack comprises side walls which extend transversely to the main extension plane of the active region,
the entire side walls are covered completely with a cover layer which is formed with at least one semiconductor material,
the cover layer completely covers and is in direct contact with the active region on the side walls,
an upper surface of the layer stack is free of the cover layer,
the cover layer does not comprise a ( 111 ) A surface on its upper surface,
the side walls comprise an inhomogeneous shape and covalent bonds exist between a material of the side walls and a material of the cover layer,
the side walls are etched more in the region of the active region than in other regions,
the cover layer comprises a greater thickness in the region of the active region than in other regions, and
an extension of the cover layer perpendicular to the main extension plane of the active layer has its maximum at the side walls.
2. The optoelectronic semiconductor body according to claim 1 , in which the lattice mismatch between a material of the cover layer and a material of the layer stack is less than 1%.
3. The optoelectronic semiconductor body according to claim 1 , in which the band gap of a material of the cover layer is larger than the band gap of a material of the layer stack.
4. The optoelectronic semiconductor body according to claim 1 , in which the side walls are free of traces of a separation process.
5. The optoelectronic semiconductor body according to claim 1 , in which the optoelectronic semiconductor body is an electrically pumpable emitter or the optoelectronic semiconductor body is an optically pumpable emitter.
6. The optoelectronic semiconductor body according to claim 1 , in which the layer stack is arranged on a substrate and at least one of the side walls encloses an angle greater than 0° and at most 30° with a crystal direction of the substrate in a plane which is parallel to the main extension plane of the active region.
7. An arrangement of a plurality of optoelectronic semiconductor bodies of claim 1 , in which the plurality of optoelectronic semiconductor bodies is arranged in a two-dimensional arrangement.
8. An optoelectronic semiconductor body, comprising:
a layer stack with:
an active region, which is configured to emit electromagnetic radiation and which comprises a main extension plane, wherein
the layer stack comprises a hexagonal shape in a plane parallel to the main extension plane of the active region,
the layer stack comprises a p-doped region and an n-doped region, wherein the active region is arranged in the stack direction between the p-doped region and the n-doped region,
the p-doped region and the n-doped region each have sidewalls that face each other and overlap in a plane that is perpendicular to the main extension plane of the active region,
a mask layer comprising a dielectric material is arranged on an upper surface of the layer stack,
the mask layer is arranged on the n-doped region and, in the region of the n-doped region, the layer stack is undercut under the mask layer,
the layer stack comprises side walls which extend transversely to the main extension plane of the active region,
the entire side walls are covered completely with a cover layer which is formed with at least one semiconductor material,
the cover layer completely covers and is in direct contact with the active region on the side walls,
an upper surface of the layer stack is free of the cover layer,
the cover layer does not comprise a ( 111 ) A surface on its upper surface,
the side walls comprise an inhomogeneous shape and covalent bonds exist between a material of the side walls and a material of the cover layer,
the side walls are etched more in the region of the active region than in other regions,
the cover layer comprises a greater thickness in the region of the active region than in other regions, and
an extension of the cover layer perpendicular to the main extension plane of the active layer has its maximum at the side walls.
9. A method for producing an optoelectronic semiconductor body comprising:
growing a layer stack with an active region which is configured to emit electromagnetic radiation and which comprises a main extension plane,
etching the layer stack so that it comprises, at least in the region of the active region, side walls which extend transversely to the main extension plane of the active region, and
growing a cover layer at least in places on the side walls of the layer stack, wherein
the cover layer is formed with at least one semiconductor material,
the side walls comprise an inhomogeneous shape and covalent bonds exist between a material of the side walls and a material of the cover layer, and
the active region is more strongly etched than the p-doped region and the n-doped region, wherein before the cover layer is grown, a material transport is induced in the region of the side walls as a result of changed growth conditions, wherein material from the regions between the layer stacks is transported to the side walls.
10. The method according to claim 9 , in which a masking layer is applied to the layer stack prior to etching the layer stack.
11. The method according to claim 9 , in which the cover layer is removed from an upper surface of the layer stack.
12. The method according to claim 9 , in which the optoelectronic semiconductor body is separated through the cover layer after growing the cover layer.
13. The method according to claim 9 , in which the cover layer is grown by metalorganic chemical vapor phase epitaxy.
14. The method according to claim 9 , in which the layer stack is etched more in the region of the active region than in other regions by irradiating the active region during etching with electromagnetic radiation.