Passivation covered light emitting unit stack

Abstract

A light emitting diode (LED) pixel for a display including a light emitting structure configured to generate light and comprising at least one active layer, a first passivation layer surrounding side surfaces and an upper portion of the light emitting structure, the first passivation layer including via holes, and a plurality of via contacts filling the via holes and electrically connected to the light emitting structure, in which the via holes do not overlap the at least one active layer, and an area of the first passivation layer is greater than that of the light emitting structure in plan view.

What is claimed is: 
     
         1 . A light emitting diode (LED) pixel for a display, comprising:
 a light emitting structure configured to generate light and comprising at least one active layer;   a first passivation layer surrounding side surfaces and an upper portion of the light emitting structure, the first passivation layer including via holes; and   a plurality of via contacts filling the via holes and electrically connected to the light emitting structure,   wherein the via holes do not overlap the at least one active layer; and   wherein an area of the first passivation layer is greater than that of the light emitting structure, in plan view.   
     
     
         2 . The LED pixel for a display of  claim 1 , wherein a bottom surface of the first passivation layer is disposed on a same plane as a bottom surface of the light emitting structure. 
     
     
         3 . The LED pixel for a display of  claim 1 , wherein the side surfaces of the light emitting structure are closer to a center of the light emitting structure than side surfaces of the first passivation layer. 
     
     
         4 . The LED pixel for a display of  claim 1 , wherein:
 the via contacts correspond to the via holes; and   each of the via contacts comprises a first portion filling the via hole and a second portion protruding from an upper surface of the first passivation layer.   
     
     
         5 . The LED pixel for a display of  claim 4 , wherein the second portion has a width greater than that of the first portion. 
     
     
         6 . The LED pixel for a display of  claim 5 , wherein:
 the at least one active layer of the light emitting structure is formed in plural; and   the second portion of the first via contact partially overlaps at least one of the active layers.   
     
     
         7 . The LED pixel for a display of  claim 1 , wherein upper surfaces of the via contacts are flush with an upper surface of the first passivation layer. 
     
     
         8 . The LED pixel for a display of  claim 1 , wherein an upper surface of the first passivation layer is disposed on a higher elevation than that of the light emitting structure. 
     
     
         9 . The LED pixel for a display of  claim 1 , wherein each of the via holes has a width that gradually decreases from top to bottom. 
     
     
         10 . The LED pixel for a display of  claim 1 , wherein the via contacts have inclined sidewalls. 
     
     
         11 . The LED pixel for a display of  claim 1 , further comprising:
 a second passivation layer disposed on the first passivation layer, and   a plurality of bumps disposed on the second passivation layer,   wherein the bumps are electrically connected to the via contacts.   
     
     
         12 . The LED pixel for a display of  claim 1 , wherein the light emitting structure comprises a plurality of light emitting parts configured to emit light having different wavelengths from each other. 
     
     
         13 . The LED pixel for a display of  claim 12 , further comprising a plurality of conductors electrically coupled with the light emitting parts, respectively. 
     
     
         14 . The LED pixel for a display of  claim 13 , wherein the conductors are disposed near corners of a light emitting area and are electrically connected to the via contacts, respectively. 
     
     
         15 . The LED pixel for a display of  claim 1 , wherein the via contacts are disposed near corners of the LED pixel. 
     
     
         16 . The LED pixel for a display of  claim 1 , wherein:
 the light emitting structure further comprises a plurality of semiconductor layers; and   the via contacts are disposed over at least one of the semiconductor layers, but do not overlay the at least one active layer.   
     
     
         17 . The LED pixel for a display of  claim 1 , wherein the first passivation layer comprises at least one of polyimide and epoxy molding compound. 
     
     
         18 . The LED pixel for a display of  claim 1 , further comprising a substrate on which the light emitting structure is disposed,
 wherein side surfaces of the substrate are flush with side surfaces of the first passivation layer.   
     
     
         19 . The LED pixel for a display of  claim 18 , wherein the substrate comprises at least one of a sapphire substrate, a SiC substrate, a GaN substrate, a InGaN substrate, an AlGaN substrate, an AlN substrate, a Ga 2 O 3  substrate, a glass substrate, and a silicon substrate. 
     
     
         20 . The LED pixel for a display of  claim 1 , wherein:
 the LED pixel comprises a light emitting diode chip; and   a separation distance from each of the via contacts to a sidewall of the first passivation layer is about half of a separation distance between two adjacent light emitting diode chips in a device to which light emitting chips are to be mounted.