Method for producing a plurality of radiation-emitting semiconductor devices with a screen for a screen printing process

1. A method for manufacturing a plurality of radiation-emitting semiconductor devices, the method comprising:

providing an auxiliary carrier;

applying a plurality of radiation-emitting semiconductor chips with front sides to the auxiliary carrier so that rear sides of the semiconductor chips are freely accessible, wherein each rear side of a respective semiconductor chip has two electrical contacts;

applying spacers to the auxiliary carrier so that the spacers directly adjoin side surfaces of the semiconductor chips; and

applying a casting compound between the semiconductor chips by a screen printing process such that a semiconductor chip assembly is formed,

wherein a screen for the screen printing process has a plurality of cover elements,

wherein each cover element covers at least one electrical contact,

wherein each semiconductor chip comprises an epitaxial semiconductor layer sequence and a mirror layer,

wherein the mirror layer is arranged between the semiconductor layer sequence and the electrical contacts, and

wherein the mirror layer has a cross-sectional area that is smaller than a cross-sectional area of the epitaxial semiconductor layer sequence forming an undercut.

2. The method according to claim 1 , further comprising separating the semiconductor chip assembly into individual semiconductor devices.

3. The method according to claim 1 , wherein the semiconductor chips comprise radiation exit surfaces with a wavelength-converting layer.

4. The method according to claim 1 ,

wherein the electrical contacts have a main surface, and

wherein the main surface of the electrical contacts is formed of a solderable coating, which is not removed during the method.

5. The method according to claim 1 , wherein the rear sides of the semiconductor chips remain at least in places free of the casting compound while applying the casting compound.

6. The method according to claim 1 , wherein each cover element covers the two electrical contacts of the respective semiconductor chip.

7. The method according to claim 1 , further comprising:

removing the auxiliary carrier from the semiconductor chip assembly; and

applying a wavelength-converting layer to a first main surface of the semiconductor chip assembly to which the auxiliary carrier was applied.

8. The method according to claim 1 , wherein the auxiliary carrier is at least partially wavelength-converting and at least partially remains in the semiconductor devices.

9. The method according to claim 1 , further comprising producing the spacers by dispensing a liquid resin, wherein each spacer has a curved outer surface whose shape is formed by a meniscus of the liquid resin.

10. The method according to claim 1 , further comprising forming the casting compound from a resin into which reflecting particles are introduced so that the casting compound is a reflective casting compound.

11. The method according to claim 10 , wherein the reflecting particles are titanium dioxide particles and have a fraction of at least 60% by weight in the resin.

12. The method according to claim 1 , wherein the cover element is up to 10% larger than the electrical contacts.

13. The method according to claim 1 , wherein the electrical contacts have a thickness of between 50 μm and 75 μm, inclusive.