Light emitting device using gan led chip

Abstract

A light emitting device is constituted by flip-chip mounting a GaN-based LED chip. The GaN-based LED chip includes a light-transmissive substrate and a GaN-based semiconductor layer formed on the light-transmissive substrate, wherein the GaN-based semiconductor layer has a laminate structure containing an n-type layer, a light emitting layer and a p-type layer in this order from the light-transmissive substrate side, wherein a positive electrode is formed on the p-type layer, the electrode containing a light-transmissive electrode of an oxide semiconductor and a positive contact electrode electrically connected to the light-transmissive electrode, and the area of the positive contact electrode is half or less of the area of the upper surface of the p-type layer.

1 . A light emitting device comprising a GaN-based LED chip fixed on a base,
 the GaN-based LED chip comprising
 a conductive light-transmissive substrate, 
 a GaN-based semiconductor layer formed on said light-transmissive substrate, the layer having a laminate structure comprising at least an n-type layer and a p-type layer, and an electrode formed on the backside of said light-transmissive substrate, 
   
       wherein
 the electrode has a contact electrode formed on the backside of said light-transmissive substrate via a light-transmissive ohmic electrode, and 
 the GaN-based LED chip is fixed with a surface on the GaN-based semiconductor layer side facing upward. 
 
     
     
         2 . A GaN-based LED chip comprising
 a conductive light-transmissive substrate,   a GaN-based semiconductor layer formed on said light-transmissive substrate, the layer having a laminate structure comprising at least an n-type layer and a p-type layer, and an electrode formed on the backside of said light-transmissive substrate,   
       wherein
 the electrode has a contact electrode formed on the backside of said light-transmissive substrate via a light-transmissive ohmic electrode composed of an oxide semiconductor. 
 
     
     
         3 . The GaN-based LED chip of  claim 2 , wherein
 the roughness of the surface of the light-transmissive ohmic electrode is less than 10 nm.   
     
     
         4 . The GaN-based LED chip of  claim 2 , wherein
 an area of said contact electrode is smaller than an area of the light-transmissive ohmic electrode.   
     
     
         5 . The GaN-based LED chip of  claim 2 , wherein
 an area of said contact electrode is less than ½ of an area of the backside of said light-transmissive substrate.   
     
     
         6 . A light emitting device comprising a GaN-based LED chip of  claim 2  fixed on a base,
 wherein
 the GaN-based LED chip is fixed with a surface on the GaN-based semiconductor layer side facing upward.