Micro LED display device and method forming the same

1. A micro LED display device, comprising:

a substrate;

a plurality of micro light-emitting diodes disposed on the substrate;

a reflective layer and a black layer sequentially stacked on the substrate, the reflective layer and the black layer cover a surface of the substrate, wherein a top surface of each micro light-emitting diode is exposed through the reflective layer and the black layer, and a sidewall of each micro light-emitting diode is covered by the reflective layer and the black layer;

a plurality of reflective banks and a plurality of black banks sequentially disposed on the black layer and exposing the top surface of the plurality of micro light-emitting diodes, wherein the reflective layer, the black layer, the plurality of reflective banks, and the plurality of black banks overlap each other in a display direction, wherein the black layer further comprises concave portions located between the plurality of micro light-emitting diodes, and the plurality of reflective banks sit on the concave portions; and

a color-conversion material covering the top surface of at least one of the plurality of micro light-emitting diodes, wherein the color-conversion material is laterally disposed between the plurality of reflective banks.

2. The micro LED display device of claim 1 , wherein a sum of a thickness of the plurality of reflective banks and a thickness of the plurality of black banks is larger than a sum of a thickness of the reflective layer and a thickness of the black layer.

3. The micro LED display device of claim 1 , wherein a surface of the concave portions is lower than the top surface of the micro light-emitting diode adjacent to the concave portions.

4. The micro LED display device of claim 1 , further comprising a plurality of color filter units disposed above the plurality of micro light-emitting diodes, respectively.

5. The micro LED display device of claim 4 , further comprising a photon recycling layer disposed between at least one of the plurality of color filter units and the color-conversion material in the display direction, wherein the photon recycling layer reflects unconverted lights back to the color-conversion material.

6. The micro LED display device of claim 4 , wherein the color-conversion material is located between at least one of the plurality of micro light-emitting diodes and at least one of the plurality of color filter units in the display direction.

7. The micro LED display device of claim 4 , further comprising a plurality of light-shielding structures laterally separating the plurality of color filter units.

8. The micro LED display device of claim 7 , wherein the plurality of light-shielding structures correspond to the plurality of black banks in the display direction.

9. The micro LED display device of claim 8 , further comprising a cover plate, wherein the plurality of light-shielding structures and the plurality of color filter units are disposed on the cover plate.

10. The micro LED display device of claim 9 , further comprising a sealant layer disposed between the substrate and the cover plate, wherein the sealant layer maintains a space between the substrate and the cover plate, and adheres the substrate to the cover plate.

11. The micro LED display device of claim 9 , further comprising an optical layer, wherein the optical layer fills a space between the substrate and the cover plate.

12. The micro LED display device of claim 10 , further comprising an air gap within the space, interposed between the plurality of micro light-emitting diodes and the plurality of color filter units.