Method of manufacturing semiconductor light emitting device

Abstract

A semiconductor light emitting device includes a light emitting structure having a rod shape with first and second surfaces opposing each other and a side surface connected between the first and second surfaces, and including a first conductivity-type semiconductor providing the first surface, an active layer and a second conductivity-type semiconductor, a first electrode layer on a first region of the first surface of the light emitting structure and connected to the first conductivity-type semiconductor, the first region having a level that is vertically offset from a level of a second region adjacent thereto, and a second electrode layer connected to the second conductivity-type semiconductor.

What is claimed is: 
     
         1 . A method of manufacturing a semiconductor light emitting device, the method comprising:
 preparing a nitride single crystal substrate having an upper surface on which a plurality of device formation regions are arranged, each of the plurality of device formation regions having a first region and a second region;   forming an electrode pattern on the first region of each of the plurality of device formation regions, the electrode pattern including the metal layer on the nitride single crystal substrate and an ohmic contact layer on the metal layer;   forming a plurality of light emitting structure on the plurality of device formation regions to cover the electrode pattern of each of the plurality of device formation, wherein the metal layer is converted into a metal nitride layer by reacting with nitrogen in the nitride single crystal substrate during the forming the plurality of light emitting structures;   removing the metal nitride layer from the ohmic contact layer; and   separating the plurality of light emitting structures from the nitride single crystal substrate by applying stress to a connection portion of each of a plurality of the light emitting structure connected to the second region.   
     
     
         2 . The method of  claim 1 , wherein the first region surrounds the second region in each of the plurality of device formation regions. 
     
     
         3 . The method of  claim 1 , wherein the electrode pattern has a ring shape. 
     
     
         4 . The method of  claim 1 , wherein the metal nitride layer includes TiN, TaN, or WN. 
     
     
         5 . The method of  claim 1 , wherein vacancies are generated in a region of the nitride single crystal substrate adjacent to the metal nitride layer. 
     
     
         6 . The method of  claim 1 , wherein forming the plurality of light emitting structure includes:
 forming a semiconductor stack by sequentially growing a first conductivity-type semiconductor layer, an active layer, and a second conductivity-type semiconductor layer on the nitride single crystal substrate,   forming an electrode layer on the semiconductor stack,   forming a plurality of mask patterns on the electrode layer, the plurality of electrode layers respectively overlapping the plurality of device formation regions in a direction perpendicular to the upper surface of the nitride single crystal substrate,   forming the plurality of light emitting structures by etching the electrode layer and the semiconductor stack using the plurality of mask patterns, and   removing the mask patterns from the plurality of light emitting structures.   
     
     
         7 . The method of  claim 6 , wherein the converting into the metal nitride layer occurs during the forming of the semiconductor stack. 
     
     
         8 . The method of  claim 6 , wherein the removing the mask patterns is performed simultaneously with the removing the metal nitride layer. 
     
     
         9 . The method of  claim 1 , wherein forming the plurality of light emitting structure includes:
 forming an amorphous insulating layer on the nitride single crystal substrate to cover the electrode pattern,   forming a plurality of nanoholes in the amorphous insulating layer to expose the plurality of device formation regions,   forming a first conductivity-type semiconductor rod in each of the plurality of nanoholes,   partially removing the amorphous insulating layer to expose an upper portion of a side surface of the first conductivity-type semiconductor rod,   sequentially forming an active layer and a second conductivity-type semiconductor layer on the upper portion of side surface of the first conductivity-type semiconductor rod,   forming an electrode layer on the second conductivity-type semiconductor layer, and   removing a remaining amorphous insulating layer from the side surface of the nitride single crystal substrate.   
     
     
         10 . The method of  claim 9 , wherein the converting into the metal nitride layer occurs during the forming of the first conductivity-type semiconductor rod. 
     
     
         11 . The method of  claim 9 , wherein:
 the amorphous insulating layer includes a first insulating film, a second insulating film, and a third insulating film sequentially laminated on the nitride single crystal substrate, and   the second insulating film includes a material different those of the first and third insulating films.   
     
     
         12 . The method of  claim 11 , wherein:
 partially removing the amorphous insulating layer includes removing the third insulating film, and   removing a remaining amorphous insulating layer includes removing the first and second insulating films.   
     
     
         13 . A method of manufacturing a semiconductor light emitting device, the method comprising:
 sequentially forming a metal layer and an ohmic contact layer on a nitride single crystal substrate;   forming a plurality of electrode patterns by patterning the metal layer and the ohmic contact layer;   forming a semiconductor stack by sequentially growing a first conductivity-type semiconductor layer, an active layer, and a second conductivity-type semiconductor layer on the nitride single crystal substrate, wherein, during the forming of the semiconductor stack, the metal layer is converted into a metal nitride layer by reacting with nitrogen in the nitride single crystal substrate;   forming a plurality of mask patterns on the semiconductor stack;   forming a plurality of light emitting structures by etching the semiconductor stack using the plurality of mask patterns;   removing the mask patterns from the plurality of light emitting structures;   removing the metal nitride layer from the ohmic contact layer; and   separating the plurality of light emitting structures from the nitride single crystal substrate.   
     
     
         14 . The method of  claim 13 , wherein each of the plurality of electrode pattern has a shape partially or completely surrounding a region on the nitride single crystal substrate. 
     
     
         15 . The method of  claim 13 , wherein vacancies are generated in a region of the nitride single crystal substrate adjacent to the metal nitride layer. 
     
     
         16 . The method of  claim 13 , wherein forming the plurality of light emitting structures includes:
 forming a plurality of preliminary light emitting structures by first etching the semiconductor stack such that a side surface of each of the plurality of preliminary light emitting structure has a damaged area in the first etching, and   removing a damaged area to form the plurality of light emitting structures by second etching the plurality of preliminary light emitting structures.   
     
     
         17 . The method of  claim 16 , wherein:
 the first etching includes dry-etching, and   the second etching includes wet etching.   
     
     
         18 . The method of  claim 16 , wherein:
 each of the mask patterns has a circular shape, and   each of the plurality of light emitting structures has a hexagonal structure.   
     
     
         19 . The method of  claim 16 , further comprising forming a passivation layer on a side surface of each of the plurality of light emitting structures prior to removing the mask patterns. 
     
     
         20 . A method of manufacturing a semiconductor light emitting device, the method comprising:
 preparing a nitride single crystal substrate having an upper surface on which a plurality of device formation regions are arranged such that each of the plurality of device formation regions has a first region and a second region;   forming an electrode pattern on the first region of each of the plurality of device formation regions such that the electrode pattern includes the metal layer on the nitride single crystal substrate and an ohmic contact layer on the metal layer;   forming an amorphous insulating layer on the nitride single crystal substrate to cover the electrode pattern;   forming a plurality of nanoholes in the amorphous insulating layer to expose the plurality of device formation regions;   forming a first conductivity-type semiconductor rod in each of the plurality of nanoholes, wherein the metal layer is converted into a metal nitride layer by reacting with nitrogen in the nitride single crystal substrate during the forming the first conductivity-type semiconductor rod;   partially removing the amorphous insulating layer to expose an upper portion of a side surface of the first conductivity-type semiconductor rod;   regrowing a first conductive-type semiconductor layer on the upper portion of the side surface of the first conductivity-type semiconductor rod;   sequentially forming an active layer and a second conductivity-type semiconductor layer on the first conductive-type semiconductor layer;   forming an electrode layer on the second conductivity-type semiconductor layer, and   removing a remaining amorphous insulating layer from the side surface of the nitride single crystal substrate.