Light-emitting device having an array of light-emitting elements

Abstract

A light-emitting device includes a substrate, a first array of light-emitting elements connected in series and arranged along a first straight line on the substrate, a p-electrode disposed on the substrate and connected to the first array, a second array of light-emitting elements connected in series, arranged along a second straight line on the substrate, and connected to the first array, and an n-electrode disposed on the substrate and connected to the second array. The p-electrode has a surface that faces and is substantially parallel to a surface of the n-electrode.

What is claimed is: 
     
         1 . A light-emitting device, comprising:
 a substrate;   a first array of light-emitting elements connected in series and arranged along a first straight line on the substrate;   a p-electrode disposed on the substrate and connected to the first array;   a second array of light-emitting elements connected in series, arranged along a second straight line on the substrate, and connected to the first array; and   an n-electrode disposed on the substrate and connected to the second array,   wherein the p-electrode has a surface that faces and is substantially parallel to a surface of the n-electrode.   
     
     
         2 . The light-emitting device of  claim 1 , wherein the first array and the second array have an equal number of light-emitting elements. 
     
     
         3 . The light-emitting device of  claim 1 , wherein the p-electrode is disposed on the first array and the n-electrode is disposed on the second array. 
     
     
         4 . The light-emitting device of  claim 1 , wherein each light-emitting element of the first array and the second array comprises:
 a n-type semiconductor layer disposed on the substrate;   a light-emitting layer disposed on the n-type semiconductor layer; and   a p-type semiconductor layer disposed on the light-emitting layer.   
     
     
         5 . The light-emitting device of  claim 4 , wherein the n-type semiconductor layer, the light-emitting layer, and the p-type semiconductor layer are GaN-based layers. 
     
     
         6 . The light-emitting device of  claim 5 , wherein:
 the p-electrode is electrically connected to a p-type semiconductor layer of a light-emitting element of the first array, and   the n-electrode is electrically connected to an n-type semiconductor layer of a light-emitting element of the second array.   
     
     
         7 . The light-emitting device of  claim 6 , further comprising:
 a first wire electrically connecting the p-electrode to the first array;   a first plurality of wires electrically connecting the light-emitting elements of the first array in series;   a second wire electrically connecting the n-electrode to the second array;   a second plurality of wires electrically connecting the light-emitting elements of the second array in series; and   a third wire electrically connecting the first array to the second array.   
     
     
         8 . The light-emitting device of  claim 7 , wherein the first wire, the first plurality of wires, the second wire, the second plurality of wires, and the third wire are air bridge lines. 
     
     
         9 . The light-emitting device of  claim 1 , wherein an overall shape of the light-emitting device is rectangular in plan view. 
     
     
         10 . The light-emitting device of  claim 9 , wherein the n- electrode and the p-electrode have a rectangular shape in plan view. 
     
     
         11 . The light-emitting device of  claim 1 , wherein the p-electrode is a transparent electrode comprising nickel (Ni) and gold (Au). 
     
     
         12 . The light-emitting device of  claim 1 , wherein the light-emitting elements of the first array have polarities opposite of the light-emitting elements of the second array. 
     
     
         13 . The light-emitting device of  claim 7 , wherein:
 the first array is configured to allow current to flow across the substrate in a first direction away from the p-electrode,   the second array is configured to allow current to flow across the substrate in a second direction toward the n-electrode, and   the first direction is parallel to and opposite of the first direction.   
     
     
         14 . The light-emitting device of  claim 13 , wherein the third wire is configured to allow current to flow in a direction that is perpendicular to the first direction and the second direction. 
     
     
         15 . The light-emitting device of  claim 8 , wherein the substrate is an insulating substrate. 
     
     
         16 . The light-emitting device of  claim 15 , wherein the insulating substrate comprises sapphire. 
     
     
         17 . The light-emitting device of  claim 16 , wherein the light-emitting layer comprises indium gallium nitride (InGaN). 
     
     
         18 . The light-emitting device of  claim 17 , wherein the air bridge lines comprise gold (Au).