LED semiconductor element having increased luminance
View Patent ↗An LED semiconductor element having at least one first radiation-generating active layer and at least one second radiation-generating active layer which is stacked above the first active layer in a vertical direction and is connected in series with the first active layer. The first active layer and the second active layer are electrically conductively connected by a contact zone.
1. An LED semiconductor element comprising:
at least one first radiation-generating active layer,
at least one second radiation-generating active layer which is stacked above the first active layer in a vertical direction and is connected in series with the first active layer,
a semiconductor layer of a first conductivity type disposed downstream of the first active layer in a vertical direction, and
a semiconductor layer of a second conductivity type arranged between the semiconductor layer of the first conductivity type and the second active layer,
wherein the first active layer and the second active layer are electrically conductively connected by means of a contact zone; and
wherein the semiconductor layer of the first conductivity type comprises a first free region not covered by semiconductor material.
2. The LED semiconductor element as claimed in claim 1 , wherein the contact zone is arranged at a side flank of the LED semiconductor element.
3. The LED semiconductor element as claimed in claim 1 , wherein the semiconductor layer of the first conductivity type and the semiconductor layer of the second conductivity type form a tunnel junction.
4. The LED semiconductor element as claimed in claim 1 , wherein the semiconductor layer of the second conductivity type comprises a second free region not covered by semiconductor material.
5. The LED semiconductor element as claimed in claim 4 , wherein the contact zone extends from the first free region to the second free region.
6. The LED semiconductor element as claimed in claim 1 , wherein the contact zone contains a transparent conductive oxide (TCO).
7. The LED semiconductor element as claimed in claim 1 , wherein the contact zone is integrated into the LED semiconductor element between the first active layer and the second active layer.
8. The LED semiconductor element as claimed in claim 7 wherein the contact zone has at least one first region and at least one second region.
9. The LED semiconductor element as claimed in claim 8 , wherein the second region is electrically conductive.
10. The LED semiconductor element as claimed in claim 7 , wherein the contact zone contains a material that is transmissive to the radiation generated by the first and/or second active layer.
11. The LED semiconductor element as claimed in claim 10 , wherein the contact zone contains a transparent conductive oxide (TCO).
12. The LED semiconductor element as claimed in claim 7 , wherein the contact zone contains an adhesion agent.