Semiconductor Light Emitting Devices And Method Of Manufacturing The Same

Abstract

Disclosed is a semiconductor light emitting device including: a plurality of semiconductor layers including an active layer adapted to generate ultraviolet light by recombination of electrons and holes; an encapsulating member adapted to surround the semiconductor light emitting device chip; and an external substrate including a base, and conductive layers electrically connected to the electrodes of the semiconductor light emitting device chip. The conductive layer is arranged inside of the encapsulating member and adapted to reflect the ultraviolet light, with the conductive layer having one face made of a substance with UV reflectivity of less than 90%. A flat area portion of the external substrate that is in contact with a lower face of the encapsulating member is smaller than a flat area portion of the external substrate that is not in contact with the lower face of the encapsulating member.

What is claimed: 
     
         1 . A semiconductor light emitting device comprising:
 a semiconductor light emitting device chip which includes a plurality of semiconductor layers, and electrodes electrically connected to the plurality of semiconductor layers, the plurality of semiconductor layers including an active layer adapted to generate ultraviolet light by recombination of electrons and holes;   an encapsulating member adapted to surround the semiconductor light emitting device chip; and   an external substrate including a base, and conductive layers electrically connected to the electrodes of the semiconductor light emitting device chip,   wherein the conductive layer is arranged inside of the encapsulating member and adapted to reflect the ultraviolet light, the conductive layer having one face made of a substance with UV reflectivity of less than 90%, and   wherein a flat area portion of the external substrate that is in contact with a lower face of the encapsulating member is smaller than a flat area portion of the external substrate that is not in contact with the lower face of the encapsulating member.   
     
     
         2 . The semiconductor light emitting device according to  claim 1 , wherein the conductive layer is arranged inside of the encapsulating member and adapted to reflect the ultraviolet light, the conductive layer having one face made of a substance with UV reflectivity of 40% or less. 
     
     
         3 . The semiconductor light emitting device according to  claim 2 , wherein the conductive layer is arranged inside of the encapsulating member and adapted to reflect the ultraviolet light, the conductive layer having one face made of Au. 
     
     
         4 . The semiconductor light emitting device according to  claim 1 , wherein the external substrate includes a barrier with a closed loop shape placed at a predefined distance from the conductive layer, and
 wherein the barrier having an upper face in contact with the lower face of the encapsulating member.   
     
     
         5 . The semiconductor light emitting device according to  claim 4 , wherein the barrier is arranged inside of the encapsulating member and adapted to reflect the ultraviolet light, the barrier having one face made of a substance with UV reflectivity of 40% or less. 
     
     
         6 . The semiconductor light emitting device according to  claim 5 , wherein the conductive layer and the barrier are arranged inside of the encapsulating member and adapted to reflect the ultraviolet light, the conductive layer and the barrier each having one face made of same metallic substances. 
     
     
         7 . The semiconductor light emitting device according to  claim 1 , wherein the encapsulating member is made of a thermoplastic resin having at least 80% UV transmissivity. 
     
     
         8 . The semiconductor light emitting device according to  claim 7 , wherein the thermoplastic resin undergoes a reduction in volume of at least 90% during a heat-curing process for solidifying the thermoplastic resin in liquid phase. 
     
     
         9 . The semiconductor light emitting device according to  claim 1 , wherein the encapsulating member has a hemispherical lens shape. 
     
     
         10 . The semiconductor light emitting device according to  claim 1 , wherein the semiconductor light emitting device chip is a flip chip that emits UV-C,
 wherein the encapsulating member is made of a thermoplastic resin having at least 80% UV transmissivity,   wherein an upper part of the conductive layer is made of a substance having UV-C reflectivity of lower than 90%, and   wherein the electrodes of the semiconductor light emitting device chip are electrically connected to the upper part of the conductive layer.