Light emitting device

Abstract

Disclosed is a light emitting device including a substrate, a light emitting structure arranged on the substrate, the light emitting structure including a first semiconductor layer, a second semiconductor layer and an active layer arranged between the first semiconductor layer and the second semiconductor layer, a first electrode electrically connected to the first semiconductor layer, and a second electrode electrically connected to the second semiconductor layer, wherein the light emitting structure has a top surface including a first side and a second side which face each other, and a third side and a fourth side which face each other.

What is claimed is: 
     
       1. A light emitting device, comprising:
 a substrate; 
 a light emitting structure arranged on the substrate, the light emitting structure including a first semiconductor layer, an active layer on the first semiconductor layer, and a second semiconductor layer and an on the active layer arranged between the first semiconductor layer and the second semiconductor layer; 
 a first electrode electrically connected to the first semiconductor layer including a first pad and a first arm; and 
 a second electrode electrically connected to the second semiconductor layer including a second pad and a second arm, 
 wherein the light emitting structure has comprises a top surface including a first side and a second side which face each other, and a third side and a fourth side which face each other having a rectangular shape in the top view, 
 wherein the first electrode includes: 
 a first electrode padthe first pad located father away from a first side of the rectangular shape than a second side of the rectangular shape, the first pad being adjacent to the edge of the second side and the third side in thean edge of the second side and a third side of the rectangular shape in an exposed part of the first semiconductor layer; and 
 a first electrodethe first arm connected to the first electrode pad, the first electrode arm extending in a first direction, and 
 wherein the second electrode includes: 
 a second electrodethe second pad adjacent to the fourth sidea fourth side of the rectangular shape on the second semiconductor layer; and 
 a second electrodethe second arm connected to the second electrode pad, the second electrode arm extending in an opposite direction to the first direction,; and 
 the distance from the first electrode arm to the second electrode arm in a second direction is 25% to 75% of the width of the second semiconductor layer in the second directiona distance from the first arm to the second arm in a second direction is 25% to 75% of a width of the second semiconductor layer in the second direction. 
 
     
     
       2. The light emitting device of  claim 1 , wherein the second electrode pad is formed adjacent to the edge between the first side and the fourth side. 
     
     
       3. The light emitting device of  claim 1 , wherein the second electrode pad is formed adjacent to the center of the width of the second semiconductor layer in the second direction. 
     
     
       4. The light emitting device of  claim 1 , wherein the first electrode arm and the second electrode arm are formed in parallel. 
     
     
       5. The light emitting device of  claim 1 , wherein at least one of the first and second electrode pads has a circular shape of a shape having a curved part. 
     
     
       6. The light emitting device of  claim 1 , wherein the first and second electrode pads have different shapes. 
     
     
       7. The light emitting device of  claim 1 , wherein the lengths of the first and second electrode arms are equivalent or one thereof is greater. 
     
     
       8. The light emitting device of  claim 1 , wherein the second electrode pad does not overlap the first electrode pad in the first direction. 
     
     
       9. The light emitting device of  claim 1 , further comprising:
 a current blocking layer arranged between a light-transmitting electrode layer and the second electrode, or between a light-transmitting electrode layer and the second semiconductor layer, or inside the light-transmitting electrode layer.   
     
     
       10. The light emitting device of  claim 9 , wherein the current blocking layer vertically partially overlaps the second electrode. 
     
     
       11. The light emitting device of  claim 1 , wherein the first electrode is arranged in one part of the first semiconductor layer formed by mesa-etching the active layer and the second semiconductor layer. 
     
     
       12. The light emitting device of  claim 1 , wherein the second electrode arm is connected to the center of the second electrode pad in the second direction. 
     
     
       13. The light emitting device of  claim 1 , wherein the second electrode arm is connected to a lower part of the second electrode pad in the second direction. 
     
     
       14. The light emitting device of  claim 1 , wherein the second electrode arm defines the first and second sides of the top surface of the light emitting structure, the second electrode pad is located at the first side, and the first electrode pad is located at the second side. 
     
     
       15. A light emitting device comprising:
 a substrate;   a light emitting structure arranged on the substrate, the light emitting structure including a first semiconductor layer, a second semiconductor layer and an active layer arranged between the first semiconductor layer and the second semiconductor layer;   a first electrode arranged on the first semiconductor layer, the first electrode including a first electrode pad and a first electrode arm extending from the first electrode pad in a first direction; and   a second electrode arranged on the second semiconductor layer, the second electrode including a second electrode pad and a second electrode arm extending parallel to the first electrode arm,   wherein   a first distance between the first electrode arm and the second electrode arm in a second direction is 25% to 75% of the width of the light emitting structure,   a second distance between one side of the second semiconductor layer and the second electrode arm adjacent thereto is 25% to 50% of the width of the second semiconductor layer, and   the second electrode arm is connected to a lower part of the second electrode pad in the second direction.   
     
     
       16. The light emitting device of  claim 15 , wherein the second electrode arm divides a top surface of the light emitting structure into first and second sides opposed to each other in the second direction, the second electrode pad is located at the first side, and the first electrode pad is located at the second side. 
     
     
       17. A light emitting device package comprising:
 a light emitting device including a light emitting diode; and   a body including a first lead frame provided with the light emitting device and a second lead frame spaced from the first lead frame,   wherein the light emitting device comprises:   a substrate;   a light emitting structure arranged on the substrate, the light emitting structure including a first semiconductor layer, a second semiconductor layer and an active layer arranged between the first semiconductor layer and the second semiconductor layer;   a first electrode arranged on the first semiconductor layer, the first electrode including a first electrode pad electrically connected to the first lead frame and a first electrode arm extending from the first electrode pad in a first direction; and   a second electrode arranged on the second semiconductor layer, the second electrode including an second electrode pad between the center of the second semiconductor layer and the one side of the second semiconductor layer, and a second electrode arm extending parallel to the first electrode pad,   wherein   a first distance between the first electrode arm and the second electrode arm in a second direction is 25% to 75% of the width of the light emitting structure, and   a second distance between the one side of the second semiconductor layer and the second electrode arm adjacent thereto is 25% to 50% of the width of the second semiconductor layer, and   the second electrode arm is connected to a lower part of the second electrode pad in the second direction.   
     
     
       18. The light emitting device of  claim 17 , wherein the second electrode arm divides a top surface of the light emitting structure into first and second sides opposed to each other in the second direction, the second electrode pad is located at the first side, and the first electrode pad is located at the second side. 
     
     
       19. The light emitting device of claim 1, wherein the second pad does not overlap with the first pad in the first direction. 
     
     
       20. The light emitting device of claim 1, wherein the second pad does not overlap with a straight line passing from a fourth vertex of the rectangular shape to a second vertex of the rectangular shape. 
     
     
       21. The light emitting device of claim 1, wherein the second pad does not overlap with the first pad in the first direction, and the second pad does not overlap with a straight line passing from a fourth vertex of the rectangular shape to a second vertex of the rectangular shape. 
     
     
       22. The light emitting device of claim 21, wherein a distance from the first arm to a second border line of the rectangular shape is smaller than a distance from the first arm to a first border line of the rectangular shape. 
     
     
       23. The light emitting device of claim 1, wherein a distance from a first border line of the rectangular shape to the second arm of the second electrode is 25% to 50% of a width of the top surface in a second direction. 
     
     
       24. The light emitting device of claim 1, wherein the second pad is disposed on a fourth region of the rectangular shape entirely, and the first pad is disposed on a second region of the rectangular shape entirely. 
     
     
       25. The light emitting device of claim 24, wherein a length of the first arm and a length of the second arm are equivalent. 
     
     
       26. The light emitting device of claim 1, wherein a length of the second arm disposed in a first region is more than 50% of a length of the first region in the first direction. 
     
     
       27. The light emitting device of claim 1, wherein a length of the first arm disposed in a third region of the rectangular shape is more than 50% of a length of the third region in the first direction. 
     
     
       28. The light emitting device of claim 1, further comprising:
 a current blocking layer arranged between a light-transmitting electrode layer and the second electrode, between the light-transmitting electrode layer and the second semiconductor layer, or inside the light-transmitting electrode layer.   
     
     
       29. The light emitting device of claim 28, wherein the current blocking layer vertically partially overlaps with the second electrode. 
     
     
       30. The light emitting device of claim 1, wherein the first and second pads have different shapes. 
     
     
       31. The light emitting device of claim 1, wherein the second arm is connected to a center part of the second pad in the second direction. 
     
     
       32. The light emitting device of claim 1, wherein the second arm is connected to a lower part of the second pad in the second direction. 
     
     
       33. A light emitting device package comprising:
 a light emitting device including a light emitting diode; and   a body including a first lead frame provided with the light emitting device and a second lead frame spaced from the first lead frame,   wherein the body includes an inclined surface forming a cavity, and the light emitting diode is disposed in the cavity,   wherein the light emitting device comprises:   a substrate;   a light emitting device structure on the substrate, the light emitting device structure including a first semiconductor layer, an active layer on the first semiconductor layer, and a second semiconductor layer on the active layer;   a first electrode including a first pad and a first arm; and   a second electrode including a second pad and a second arm,   wherein the light emitting structure comprises a top plane surface having a rectangular shape in the top view,   wherein the top plane surface includes a first upper surface of the first semiconductor layer and a second upper surface of the second semiconductor layer,   wherein the first upper surface is not overlapped with the second semiconductor layer in the top view,   wherein the top plane surface comprises a first border line, a second border line parallel to the first border line in a first direction, a third border line, and a fourth border line parallel to the third border line in a second direction perpendicular to the first direction,   wherein the first border line is longer than the third border line and the fourth border line, and the second border line is longer than the third border line and the fourth border line,   wherein the top plane surface comprises four regions divided by a first straight line passing from a center point of the first border line of the top plane surface to a center point of the second border line of the top plane surface, and a second straight line passing from a center point of the third border line of the top plane surface to a center point of the fourth border line of the top plane surface,   wherein the four regions comprise a first region, a second region, a third region, and a fourth region,   wherein the first region has a first vertex formed by a first intersection of the first border line of the top plane surface and the third border line of the top plane surface,   wherein the second region has a second vertex formed by a second intersection of the first border line of the top plane surface and the fourth border line of the top plane surface,   wherein the third region has a third vertex formed by a third intersection of the second border line of the top plane surface and the fourth border line of the top plane surface,   wherein the fourth region has a fourth vertex formed by a fourth intersection of the second border line of the top plane surface and the third border line of the top plane surface,   wherein the top plane surface includes an overlapped portion where both the first arm of the first electrode and the second arm of the second electrode overlap each other in the second direction,   wherein a shortest distance between the first arm of the first electrode and the second arm of the second electrode is a range from 25% to 75% of a width of the top plane surface of the overlapped portion of the top plane surface in the second direction, and   wherein the first arm is connected to an edge of the first pad in the second direction and the second arm is connected to a center of the second pad in the second direction.   
     
     
       34. The light emitting device of claim 33, wherein a distance from the first border line to the second arm of the second electrode is 25% to 50% of a width of the top plane surface in the second direction. 
     
     
       35. A light emitting device, comprising:
 a substrate;   a light emitting device structure on the substrate, the light emitting device structure including a first semiconductor layer, an active layer on the first semiconductor layer, and a second semiconductor layer on the active layer;   a first electrode including a first pad and a first arm; and   a second electrode including a second pad and a second arm,   wherein the light emitting structure comprises a top plane surface having a rectangular shape in the top view,   wherein the top plane surface includes a first upper surface of the first semiconductor layer and an a second upper surface of the second semiconductor layer,   wherein the first upper surface is not overlapped with the second semiconductor layer in the top view,   wherein the top plane surface comprises a first border line, a second border line parallel to the first border line in a first direction, a third border line, and a fourth border line parallel to the third border line in a second direction perpendicular to the first direction,   wherein the top plane surface comprises four regions divided by a first straight line passing from a center point of the first border line of the top plane surface to a center point of the second border line of the top plane surface, and a second straight line passing from a center point of the third border line of the top plane surface to a center point of the fourth border line of the top plane surface,   wherein the four regions comprise a first region, a second region, a third region, and a fourth region,   wherein the first region has a first vertex formed by a first intersection of the first border line of the top plane surface and the third border line of the top plane surface,   wherein the second region has a second vertex formed by a second intersection of the first border line of the top plane surface and the fourth border line of the top plane surface,   wherein the third region has a third vertex formed by a third intersection of the second border line of the top plane surface and the fourth border line of the top plane surface,   wherein the fourth region has a fourth vertex formed by a fourth intersection of the second border line of the top plane surface and the third border line of the top plane surface,   wherein the top plane surface includes an overlapped portion where both the first arm of the first electrode and the second arm of the second electrode overlap each other in the second direction, and   wherein a distance between the first arm of the first electrode and the second arm of the second electrode is a range from 25% to 75% of a width of the top plane surface of the overlapped portion of the second semiconductor layer in the second direction.   
     
     
       36. The light emitting device of claim 35, wherein the second pad does not overlap with the first pad in the first direction. 
     
     
       37. The light emitting device of claim 35, wherein the second pad does not overlap with a straight line passing from the fourth vertex to the second vertex.