Light emitting device and lighting system with the same
Embodiments provide a light emitting device including a light emitting structure having a first conduction type semiconductor layer, an active layer, and a second conduction type semiconductor layer, a metal filter of an irregular pattern on the light emitting structure, and openings between the irregular patterns in the metal filter.
1. A light emitting device comprising:
a light emitting structure having a first conduction type semiconductor layer, an active layer, and a second conduction type semiconductor layer;
an ohmic layer disposed below the light emitting structure;
a transparent conductive layer disposed on the light emitting structure;
a passivation layer disposed at a side surface of the light emitting structure extended to sides and a top side of the transparent conductive layer; and
a metal filter having an irregular pattern disposed in the transparent conductive layer, the metal filter having metal stripes and openings between the metal stripes,
wherein an upper portion of a side surface of the second conduction type semiconductor layer directly contacts the passivation layer,
wherein a lower portion of the side surface of the second conduction type semiconductor layer is opened,
wherein an outer width of the opened lower portion of the second conduction type semiconductor layer is smaller than a width of the passivation layer, and
wherein a lower surface of the passivation layer is separated from an upper surface of the ohmic layer.
2. The light emitting device as claimed in claim 1 , wherein the metal filter includes aluminum or titanium.
3. The light emitting device as claimed in claim 1 , wherein the metal filter reflects a light from the light emitting structure.
4. The light emitting device as claimed in claim 1 , wherein the light emitting structure has a roughness disposed on a surface thereof.
5. The light emitting device as claimed in claim 1 , wherein the metal filter has a stripe type pattern.
6. The light emitting device as claimed in claim 1 , wherein the metal filter has a mesh type pattern.
7. The light emitting device as claimed in claim 1 , wherein the metal stripes have irregular widths and the openings have regular widths.
8. The light emitting device as claimed in claim 1 , wherein the openings have irregular widths and the metal stripes have regular widths.
9. The light emitting device as claimed in claim 1 , wherein at least one of the metal stripes has a first side width and a second side width, and the first side width is different from the second side width.
10. The light emitting device as claimed in claim 1 , wherein a width of one of the metal stripes is 10% to 20% of the opening width.
11. The light emitting device as claimed in claim 1 , wherein the metal filter has a thickness of 1 μm to 10 μM.
12. The light emitting device as claimed in claim 1 , wherein the passivation layer is formed of a non-conductive oxide or a non-conductive nitride.
13. A lighting system comprising:
a light emitting device package including:
a light emitting structure having a first lead frame, a second lead frame, a first conduction type semiconductor layer, an active layer, and a second conduction type semiconductor layer;
an ohmic layer disposed below the light emitting structure;
a transparent conductive layer disposed on the light emitting structure;
a passivation layer disposed at a side surface of the light emitting structure extended to sides and a top side of the transparent conductive layer; and
a metal filter having an irregular pattern disposed in the transparent conductive layer, the metal filter having metal stripes and openings between the metal stripes,
wherein an upper portion of a side surface of the second conduction type semiconductor layer directly contacts the passivation layer,
wherein a lower portion of the side surface of the second conduction type semiconductor layer is opened,
wherein an outer width of the opened lower portion of the second conduction type semiconductor layer is smaller than a width of the passivation layer, and
wherein a lower surface of the passivation layer is separated from an upper surface of the ohmic layer,
a circuit board having the light emitting device package arranged thereto; and
an optical member for forwarding a light from the light emitting device package.
14. The lighting system as claimed in claim 13 , wherein the metal filter reflects a light from the light emitting structure.
15. The lighting system as claimed in claim 13 , wherein at least one of the metal stripes has a first side width and a second side width, and the first side width is different from the second side width.
16. The lighting system as claimed in claim 13 , wherein the passivation layer is formed of a non-conductive oxide or a non-conductive nitride.
17. The light emitting device as claimed in claim 1 , further comprising a metal support disposed below the ohmic layer,
wherein the outer width of the opened lower portion of the second conduction type semiconductor layer is less than a width of the metal support.
18. The light emitting device as claimed in claim 1 , wherein a top side of one portion of the transparent conductive layer is covered by the passivation layer, and a top side of another portion of the transparent conductive layer is opened.
19. The lighting system as claimed in claim 13 , wherein the light emitting device package further comprises a metal support disposed below the ohmic layer, and
wherein the outer width of the opened lower portion of the second conduction type semiconductor layer is less than a width of the metal support.
20. The lighting system as claimed in claim 13 , wherein a top side of one portion of the transparent conductive layer is covered by the passivation layer, and a top side of another portion of the transparent conductive layer is opened.