Eutectic Electrode Structure of Flip-chip LED Chip and Flip-chip LED Chip

Abstract

A light emitting diode includes: a light emitting layer arranged on at least part of a first semiconductor layer, and a second semiconductor layer; a local defect region over a portion of the second semiconductor layer and extending downward to the first semiconductor layer; a metal layer over a portion of the second semiconductor layer; an insulating layer covering the metal layer, the second and first semiconductor layers in the local defect region, with opening structures over the local defect region and the metal layer, respectively; and an electrode structure over the insulating layer and having a first layer and a second layer, and including a first-type electrode region and a second-type electrode region; wherein an upper surface and a lower surface of the first layer are not flat, and a lower surface of the second layer are both flat.

What is claimed is: 
     
         1 . A light emitting device, comprising:
 a light emitting structure including a first semiconductor layer, a light emitting layer arranged on at least part of the first semiconductor layer, and a second semiconductor layer arranged on the light emitting layer;   a local defect region over a portion of the second semiconductor layer, the local defect region extending downward to the first semiconductor layer;   a metal layer over a portion of the second semiconductor layer;   an insulating layer covering the metal layer, the second semiconductor layer and the first semiconductor layer in the local defect region, wherein the insulating layer has opening structures over the local defect region and the metal layer, respectively; and   an electrode structure over the insulating layer, wherein the electrode structure comprises a first layer and a second layer from bottom up in a vertical direction, and includes a first-type electrode region and a second-type electrode region in a horizontal direction;   wherein an upper surface and a lower surface of the first layer are not flat, and a lower surface of the second layer are both flat.   
     
     
         2 . The light emitting device of  claim 1 , wherein an upper surface of the second layer is higher than or is of equal height with the upper surface of the first layer to thereby form a flat eutectic plane. 
     
     
         3 . The light emitting device of  claim 1 , wherein the second layer does not overlap with the local defect region at the vertical direction. 
     
     
         4 . The light emitting device of  claim 1 , wherein the second layer in the first-type electrode region is of same height with the second layer in the second-type electrode region. 
     
     
         5 . The light emitting device of  claim 1 , wherein the first layer has an area larger than that of the second layer. 
     
     
         6 . The light emitting device of  claim 1 , wherein the second layer does not overlap with the opening structures of the insulating layer. 
     
     
         7 . The light emitting device of  claim 1 , wherein a transparent conducting layer is formed over the second semiconductor layer. 
     
     
         8 . The light emitting device of  claim 1 , wherein the first layer in the second-type electrode region does not overlap with the local defect region at the vertical direction. 
     
     
         9 . The light emitting device of  claim 8 , wherein the first layer in the first-type electrode region overlaps with the local defect region at the vertical direction. 
     
     
         10 . The light emitting device of  claim 1 , further comprising a package substrate which electrically connected to the electrode structure. 
     
     
         11 . The light emitting device of  claim 10 , wherein the second layer is bonded to the package substrate. 
     
     
         12 . The light emitting device of  claim 1 , wherein the metal layer comprises at least one of Cr, Ti, Pt, Au, Ag, Ni, Cu, and TiW. 
     
     
         13 . The light emitting device of  claim 1 , wherein the insulating layer comprises at least one of SiO 2 , Al 2 O 3 , SiN X , and TiO 2 . 
     
     
         14 . The light emitting device of  claim 1 , wherein the electrode structure comprises at least one of Ti, Ni, Cu, Au, AuSn, SnCu, and SnBi. 
     
     
         15 . The light emitting device of  claim 1 , wherein the opening structures include a first number of openings in the first-type electrode region, and a second number of openings in the second-type electrode region, and wherein the first number is smaller than the second number. 
     
     
         16 . The light emitting device of  claim 1 , wherein the light emitting structure has a surface distal from the first semiconductor layer in a vertical direction and having a first region and a second region, the first-type electrode region of the second layer is arranged on the first region, the second-type electrode region of the second electrode layer is arranged on the second region. 
     
     
         17 . The light emitting device of  claim 1 , wherein the metal layer having a part corresponding to the second region of the surface, and another part corresponding to the first region of the surface. 
     
     
         18 . A light-emitting system comprising a plurality of light emitting devices each including:
 a light emitting structure including a first semiconductor layer, a light emitting layer arranged on at least part of the first semiconductor layer, and a second semiconductor layer arranged on the light emitting layer;   a local defect region over a portion of the second semiconductor layer, the local defect region extending downward to the first semiconductor layer;   a metal layer over a portion of the second semiconductor layer;   an insulating layer covering the metal layer, the second semiconductor layer and the first semiconductor layer in the local defect region, wherein the insulating layer has opening structures over the local defect region and the metal layer, respectively; and   an electrode structure over the insulating layer, wherein the electrode structure comprises a first layer and a second layer from bottom up in a vertical direction, and includes a first-type electrode region and a second-type electrode region in a horizontal direction;   wherein an upper surface and a lower surface of the first layer are not flat, and a lower surface of the second layer are both flat.   
     
     
         19 . The light-emitting system of  claim 18 , wherein
 an upper surface of the second layer is higher than or is of equal height with the upper surface of the first layer to thereby form a flat eutectic plane.   
     
     
         20 . The light-emitting system of  claim 18 , wherein
 the opening structures include a first number of openings in the first-type electrode region, and a second number of openings in the second-type electrode region, and wherein the first number is smaller than the second number;   the first-type electrode region is an N-type electrode region, the second-type electrode region is a P-type electrode region, wherein a ratio between the first number and the second number is in a range of 0.3-0.9;   the metal layer is composed of metal bodies and metal spreading fingers; and   the opening structures of the insulating layer are only over the metal body.