μ-LED, μ-LED device, display and method for the same
The invention relates to various aspects of a μ-LED or a μ-LED array for augmented reality or lighting applications, in particular in the automotive field. The μ-LED is characterized by particularly small dimensions in the range of a few μm.
1. A μ-LED comprising:
an n-doped first layer;
a p-doped second layer doped with a first dopant;
an active layer which is disposed between the n-doped first layer and the p-doped second layer and which comprises at least one quantum well;
wherein the active layer is divided into at least two circular regions;
wherein a second region of the at least two circular regions concentrically encloses a first region of the at least two circular regions;
wherein the at least one quantum well in the active layer comprises a second band gap in the second region that is larger than a first band gap in the first region; and
wherein the second region comprises a dopant concentration configured to modify the second band gap by quantum well intermixing.
2. The μ-LED according to claim 1 , further comprising a second dopant which is substantially arranged uniformly in the second region.
3. The μ-LED according to claim 2 , wherein the second dopant in the second region is also located in the p-doped second layer and in the active layer, and is at least partially formed in a region of the n-doped first layer adjacent to the active layer.
4. The μ-LED according to claim 2 , wherein the second dopant is different from the first dopant.
5. The μ-LED according to claim 2 , wherein the second dopant is formed from a group comprising at least one of Mg, Zn, and/or Cd.
6. The μ-LED according to claim 1 , wherein the second region comprises a substantially uniform band gap change modified by the quantum well intermixing.
7. The μ-LED according to claim 1 , wherein the first region comprises substantially no quantum well intermixing.
8. The μ-LED according to claim 1 , wherein quantum well inter-mixing decreases in a defined transition area from the second region to the first region.
9. A μ-LED arrangement with a plurality of μ-LEDs according to claim 1 and further comprising:
a photonic structure arranged on a side located in a main emission direction; and
with a contact area on the side opposite the main emission direction.
10. The μ-LED arrangement according to claim 9 , wherein the photonic structure is formed by a periodic array of columnar elements comprising a first refractive index surrounded by material comprising a second refractive index, at least some of the columnar elements being located above the active layer, in particular above the first region.
11. The μ-LED arrangement according to claim 9 , wherein at least one of the plurality of μ-LEDs is surrounded by a circumferential reflecting structure.