Micro light emitting device and display apparatus having the same
Provided is a micro light emitting device and a display apparatus having the micro light emitting device. The micro light emitting device includes a first-type semiconductor layer provided on a substrate, a superlattice layer provided on the first-type semiconductor layer, a current blocking layer provided on a side portion of the superlattice layer, an active layer provided on the superlattice layer and the current blocking layer, and a second-type semiconductor layer provided on the active layer.
1. A micro light emitting device comprising:
a substrate;
a first-type semiconductor layer provided on the substrate;
a superlattice layer provided on the first-type semiconductor layer;
a current blocking layer provided at a side portion of the superlattice layer;
an active layer directly provided on the superlattice layer and the current blocking layer;
a second-type semiconductor layer provided on the active layer,
wherein the superlattice layer has a first layer and a second layer that are alternatively stacked, and the superlattice layer has a bandgap greater than the active layer.
2. The micro light emitting device of claim 1 , wherein the current blocking layer comprises a porous layer or an air layer.
3. The micro light emitting device of claim 2 , wherein the porous layer comprises a gallium nitride.
4. The micro light emitting device of claim 1 , wherein the current blocking layer comprises:
a porous layer that contacts the side portion of the superlattice layer; and
an air layer provided on a side portion of the porous layer.
5. The micro light emitting device of claim 1 , wherein the current blocking layer extends from the side portion of the superlattice layer to a side portion of the first-type semiconductor layer or a bottom of the first-type semiconductor layer.
6. The micro light emitting device of claim 1 , wherein the current blocking layer extends from the side portion of the superlattice layer to a side portion of the active layer.
7. The micro light emitting device of claim 1 , further comprising a nano rod type micro light emitting device.
8. The micro light emitting device of claim 1 , wherein the current blocking layer is provided extending from the side portion of the superlattice layer to a side portion of the first-type semiconductor layer or a bottom of the first-type semiconductor layer.
9. The micro light emitting device of claim 1 , further comprising a protection layer provided on a side wall of the active layer, a side wall of the second-type semiconductor layer, and an exposed surface of the current blocking layer.
10. The micro light emitting device of claim 1 , further comprising a via hole that extends through the second-type semiconductor layer, the active layer and the current blocking layer and into the first-type semiconductor layer.
11. The micro light emitting device of claim 10 , wherein the current blocking layer is further provided along a circumference of the via hole of the first-type semiconductor layer.
12. The micro light emitting device of claim 1 , wherein the micro light emitting device has a diameter of about 200 μm or less.
13. The micro light emitting device of claim 1 , wherein the superlattice layer comprises InGaN layers and GaN layers that are alternately stacked.
14. A display apparatus comprising:
a driving circuit substrate; and
a plurality of micro light emitting devices arranged to be electrically connected to the driving circuit substrate,
wherein each of the plurality of micro light emitting devices comprises:
a first-type semiconductor layer,
a superlattice layer provided on the first-type semiconductor layer,
a current blocking layer provided on a side portion of the superlattice layer,
an active layer directly provided on the superlattice layer and the current blocking layer, and
a second-type semiconductor layer provided on the active layer, and
wherein the superlattice layer has a first layer and a second layer that are alternatively stacked, and the superlattice layer has a bandgap greater than the active layer.
15. The display apparatus of claim 14 , wherein the current blocking layer comprises a porous layer or an air layer.
16. The display apparatus of claim 15 , wherein the porous layer comprises a gallium nitride.
17. The display apparatus of claim 14 , wherein the current blocking layer comprises:
a porous layer that contacts the side portion of the superlattice layer; and
an air layer provided on a side portion of the porous layer.
18. The display apparatus of claim 14 , wherein the current blocking layer extends from the side portion of the superlattice layer to a side portion of the first-type semiconductor layer or a bottom of the first-type semiconductor layer.
19. The display apparatus of claim 14 , wherein the current blocking layer extends from the side portion of the superlattice layer to a side portion of the active layer.
20. The display apparatus of claim 14 , wherein the current blocking layer extends from the side portion of the superlattice layer to a side portion of the first-type semiconductor layer or a bottom of the first-type semiconductor layer.
21. The display apparatus of claim 14 , further comprising a protection layer on a side wall of the active layer, a sidewall of the second-type semiconductor layer, and an exposed surface of the current blocking layer.
22. The display apparatus of claim 14 , further comprising a via hole penetrating from the second-type semiconductor layer to the first-type semiconductor layer, wherein the current blocking layer is provided around the via hole of the superlattice layer.
23. The display apparatus of claim 14 , wherein each micro light emitting device of the plurality of micro light emitting devices has a diameter of about 200 μm or less.
24. The display apparatus of claim 14 , wherein the superlattice layer comprises InGaN layers and GaN layers that are alternately stacked.
25. The display apparatus of claim 14 , further comprising a color conversion layer configured to change a color of light emitted from the plurality of micro light emitting devices.
26. The display apparatus of claim 14 , wherein the display apparatus is applied to a micro LED TV, a digital signage, a mobile display apparatus, a wearable display apparatus, a virtual reality apparatus, or an augmented reality apparatus.
27. A micro light emitting device comprising:
a substrate;
a first semiconductor layer provided on the substrate;
a superlattice layer provided on the first semiconductor layer;
a high resistance layer surrounding at least a portion of a peripheral region the superlattice layer;
an active layer directly provided on the superlattice layer; and
a second semiconductor layer provided on the active layer,
wherein the high resistance layer has a higher resistance than the superlattice layer, and
wherein the superlattice layer has a first layer and a second layer that are alternatively stacked, and the superlattice layer has a bandgap greater than the active layer.
28. A micro light emitting device comprising:
a substrate;
a first semiconductor layer provided on the substrate;
a superlattice layer provided on a first portion of a first surface of the first semiconductor a high resistance layer provided on a second portion of the first surface of the first semiconductor layer;
an active layer directly provided on the superlattice layer; and
a second semiconductor layer provided on the active layer,
wherein the high resistance layer has a higher resistance than the superlattice layer, and
wherein the superlattice layer has a first layer and a second layer that are alternatively stacked, and the superlattice layer has a bandgap greater than the active layer.