Method for producing a nitride compound semiconductor device

1. A method for producing a nitride compound semiconductor device, the method comprising:

growing a first nitride compound semiconductor layer onto a growth substrate;

depositing a masking layer;

growing a second nitride compound semiconductor layer onto the masking layer;

growing a third nitride compound semiconductor layer onto the second nitride compound semiconductor layer such that the third nitride compound semiconductor layer has non-planar structures;

growing a fourth nitride compound semiconductor layer onto the non-planar structures such that the fourth nitride compound semiconductor layer has an essentially planar surface;

growing a functional layer sequence of the nitride compound semiconductor device;

connecting a side of the functional layer sequence located opposite to the growth substrate to a carrier;

removing the growth substrate; and

producing coupling-out structures on a surface of the nitride compound semiconductor device facing away from the carrier by an etching process which removes at least part of the first, second and third nitride compound semiconductor layers,

wherein the method is performed in the recited order.

2. The method according to claim 1 , wherein the non-planar structures are pyramidal structures.

3. The method according to claim 1 , wherein the non-planar structures include side facets which are constituted by a [1-101] crystal face or an [11-22] crystal face.

4. The method according to claim 1 , wherein at least part of the coupling-out structures are constituted by a [1-101] crystal face or an [11-22] crystal face.

5. The method according to claim 1 , wherein the non-planar structures have an average height of between 1 μm and 5 μm.

6. The method according to claim 1 , wherein the etching process is a wet chemical etching process.

7. The method according to claim 1 , wherein the second nitride compound semiconductor layer and/or the fourth nitride compound semiconductor layer are produced at a growth temperature higher than 1,050° C.

8. The method according to claim 1 , wherein the third nitride compound semiconductor layer is produced at a growth temperature which is by at least 40° C. lower than the growth temperature of the second nitride compound semiconductor layer.

9. The method according to claim 1 , wherein the nitride compound semiconductor layers are produced by a metal organic vapor phase epitaxy, wherein NH 3 is used as a reaction gas, and wherein an NH 3 gas flow is at least 70% smaller in an formation of the second and third nitride compound semiconductor layers than in an formation of the fourth nitride compound semiconductor layer.

10. The method according to claim 1 , wherein the masking layer is a silicon nitride layer.

11. The method according to claim 1 , wherein the masking layer has a plurality of openings of an average lateral extent of between 100 nm and 1,000 nm.

12. The method according to claim 1 , wherein the growth substrate is a sapphire substrate.

13. The method according to claim 1 , wherein the functional layer sequence includes an n-type semiconductor region, a p-type semiconductor region, and an active layer disposed between the n-type semiconductor region and the p-type semiconductor region.

14. The method according to claim 1 , wherein the nitride compound semiconductor device is a light-emitting diode.