Nitride semiconductor light emitting device and method of manufacturing the same

Abstract

A nitride semiconductor light emitting device includes a conductive substrate, a first metal layer, a second conductivity-type semiconductor layer, an emission layer, and a first conductivity-type semiconductor layer in this order. The nitride semiconductor light emitting device additionally has an insulating layer covering at least side surfaces of the second conductivity-type semiconductor layer, the emission layer and the first conductivity-type semiconductor layer. A method of manufacturing the same is provided. The nitride semiconductor light emitting device may further include a second metal layer. Thus, a reliable nitride semiconductor light emitting device and a method of manufacturing the same are provided in which short-circuit at the PN junction portion and current leak is reduced as compared with the conventional examples.

1 - 33 . (canceled) 
     
     
         34 . A method of manufacturing a nitride semiconductor light emitting device comprising the steps of:
 (A) stacking a first conductivity-type semiconductor layer, an emission layer, and a second conductivity-type semiconductor layer in this order on a first substrate;   (B) forming a plurality of depression portions at approximately regular intervals on an exposed surface of the stacked layers, each having a depth at least reaching that surface of said first conductivity-type semiconductor layer which faces said emission layer;   (C) forming an insulating layer on the entire exposed surface of the stacked layers, including a side wall and a bottom surface of said depression portion;   (D) exposing part of a surface of a layer in contact with said insulating layer by removing part of said insulating layer;   (E) stacking a first metal layer and a second substrate in this order on the entire exposed surface; and   (F) obtaining a plurality of nitride semiconductor light emitting devices by performing chip division.   
     
     
         35 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 34 , further comprising the step (G) of stacking a second metal layer, between said step (A) and said step (B). 
     
     
         36 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 34 , further comprising the step (G) of stacking a second metal layer, between said step (B) and said step (C). 
     
     
         37 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 34 , further comprising the step (H) of removing whole or part of said first substrate, after said step (E). 
     
     
         38 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 37 , further comprising the step (I) of removing part of said first conductivity-type semiconductor layer to expose a bottom surface of said depression portion, after said step (H). 
     
     
         39 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 38 , wherein in said step (I), part of said first conductivity-type semiconductor layer is removed and projections and depressions are formed on a surface of said first conductivity-type semiconductor layer. 
     
     
         40 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 38 , wherein removal of said first substrate in said step (H) and removal of said first conductivity-type semiconductor layer in said step (I) are performed by laser light radiation. 
     
     
         41 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 39 , wherein removal of said first substrate in said step (H) and removal of said first conductivity-type semiconductor layer and formation of projections and depressions on a surface of said first conductivity-type semiconductor layer in said step (I) are performed by laser light radiation. 
     
     
         42 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 34 , wherein in said step (F), a position subjected to chip division is any position on a bottom surface of said depression portion. 
     
     
         43 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 34 , wherein formation of said depression portion in said step (B) is performed by etching. 
     
     
         44 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 34 , wherein stacking of said second substrate in said step (E) is performed by bonding a first eutectic bonding layer included in said first metal layer and a second eutectic bonding layer formed on said second substrate to each other. 
     
     
         45 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 44 , wherein bonding of said first eutectic bonding layer and said second eutectic bonding layer is performed at 280-400° C. 
     
     
         46 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 44 , wherein bonding of said first eutectic bonding layer and said second eutectic bonding layer is performed under a reduced pressure of 10 Pa or lower. 
     
     
         47 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 34 , wherein stacking of said second substrate in said step (E) is performed by a plating method. 
     
     
         48 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 47 , wherein said second substrate is formed of a metal or an alloy having a thickness of 50 μm or more. 
     
     
         49 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 35 , wherein in said step (D), said second metal layer functions as an etching stop layer. 
     
     
         50 . The method of manufacturing a nitride semiconductor light emitting device according to  claim 34 , wherein in said step (E), said first metal layer is formed in a discontinuous manner at approximately regular intervals.