Light emitting diode device

Abstract

The present invention relates to a light emitting diode (LED) and a flip-chip packaged LED device. The present invention provides an LED device. The LED device is flipped on and connected electrically with a packaging substrate and thus forming the flip-chip packaged LED device. The LED device mainly has an Ohmic-contact layer and a planarized buffer layer between a second-type doping layer and a reflection layer. The Ohmic-contact layer improves the Ohmic-contact characteristics between the second-type doping layer and the reflection layer without affecting the light emitting efficiency of the LED device and the flip-chip packaged LED device. The planarized buffer layer id disposed between the Ohmic-contact layer and the reflection layer for smoothening the Ohmic-contact layer and hence enabling the reflection layer to adhere to the planarized buffer layer smoothly. Thereby, the reflection layer can have the effect of mirror reflection and the scattering phenomenon on the reflected light can be reduced as well.

1 . A light emitting diode device, comprising:
 a first-type doping layer;   a second-type doping layer;   a light emitting layer disposed between the first-type doping layer and the second-type doping layer;   an Ohmic-contact layer disposed on the second-type doping layer;   a material layer disposed on the Ohmic-contact layer, the material layer at least comprising a metal oxide layer;   a first electrode disposed on and electrically connected to the first-type doping layer;   a second electrode; and   a metal layer disposed between the second electrode and the Ohmic-contact layer, the second electrode being electrically connected to the Ohmic-contact layer through the metal layer.   
     
     
         2 . The light emitting diode device of  claim 1 , wherein a light transmittance of the Ohmic-contact layer is greater than 90%. 
     
     
         3 . The light emitting diode device of  claim 1 , wherein a light transmittance of the material layer is greater than 95%. 
     
     
         4 . The light emitting diode device of  claim 1  further comprising a cover layer, wherein the cover layer is disposed on the metal layer and extends to a sidewall of the metal layer. 
     
     
         5 . The light emitting diode device of  claim 1 , wherein a portion of the light emitted from the light emitting layer passes through the Ohmic-contact layer as well as the material layer and is reflected by the metal layer. 
     
     
         6 . A light emitting diode device, comprising:
 a first-type doping layer;   a second-type doping layer;   a light emitting layer disposed between the first-type doping layer and the second-type doping layer;   an Ohmic-contact layer disposed on the second-type doping layer;   an oxide stacking layer comprising a plurality of oxide layers stacked on the Ohmic-contact layer;   a first electrode disposed on and electrically connected to the first-type doping layer;   a second electrode electrically connected to the Ohmic-contact layer; and   a metal reflection layer, wherein the oxide stacking layer and the metal reflection layer are disposed between the second electrode and the Ohmic-contact layer.   
     
     
         7 . The light emitting diode device of  claim 6 , wherein a light transmittance of the Ohmic-contact layer is greater than 90%. 
     
     
         8 . The light emitting diode device of  claim 6 , wherein a portion of the light emitted from the light emitting layer passes through the Ohmic-contact layer and is reflected by the metal reflection layer. 
     
     
         9 . A light emitting diode device, comprising:
 a first-type doping layer;   a second-type doping layer;   a light emitting layer disposed between the first-type doping layer and the second-type doping layer;   an Ohmic-contact layer disposed on the second-type doping layer;   an oxide stacking layer comprising a plurality of oxide layers stacked on the Ohmic-contact layer;   a first electrode disposed on and electrically connected to the first-type doping layer;   a second electrode electrically connected to the Ohmic-contact layer; and   a metal reflection layer, wherein the oxide stacking layer and the metal reflection layer are disposed between the second electrode and the Ohmic-contact layer, and the second electrode is electrically connected to the Ohmic-contact layer through the metal reflection layer.   
     
     
         10 . The light emitting diode device of  claim 9 , wherein a light transmittance of the Ohmic-contact layer is greater than 90%. 
     
     
         11 . The light emitting diode device of  claim 9 , wherein a portion of the light emitted from the light emitting layer passes through the Ohmic-contact layer and is reflected by the metal reflection layer. 
     
     
         12 . A light emitting diode device, comprising:
 a first-type doping layer;   a second-type doping layer;   a light emitting layer disposed between the first-type doping layer and the second-type doping layer;   an Ohmic-contact layer disposed on the second-type doping layer;   a first electrode disposed on and electrically connected to the first-type doping layer;   a second electrode electrically connected to the Ohmic-contact layer;   a metal reflection layer disposed between the second electrode and the Ohmic-contact layer; and   at least one oxide layer disposed between the Ohmic-contact layer and the metal reflection layer.   
     
     
         13 . The light emitting diode device of  claim 12 , wherein a light transmittance of the Ohmic-contact layer is greater than 90%. 
     
     
         14 . The light emitting diode device of  claim 12 , wherein a light transmittance of the oxide layer is greater than 95%. 
     
     
         15 . The light emitting diode device of  claim 12  further comprising a cover layer, wherein the cover layer is disposed between the Ohmic-contact layer and the second electrode. 
     
     
         16 . The light emitting diode device of  claim 12 , wherein a portion of the light emitted from the light emitting layer passes through the Ohmic-contact layer as well as the oxide layer and is reflected by the metal reflection layer. 
     
     
         17 . A light emitting diode device, comprising:
 a first-type doping layer;   a second-type doping layer;   a light emitting layer disposed between the first-type doping layer and the second-type doping layer;   an Ohmic-contact layer disposed on the second-type doping layer;   a first electrode disposed on and electrically connected to the first-type doping layer;   a second electrode;   a metal reflection layer disposed between the second electrode and the Ohmic-contact layer; and   at least one oxide layer disposed between the Ohmic-contact layer and the metal reflection layer, wherein the second electrode is electrically connected the Ohmic-contact layer through the metal reflection layer.   
     
     
         18 . The light emitting diode device of  claim 17 , wherein a light transmittance of the Ohmic-contact layer is greater than 90%. 
     
     
         19 . The light emitting diode device of  claim 17 , wherein a light transmittance of the oxide layer is greater than 95%. 
     
     
         20 . The light emitting diode device of  claim 17  further comprising a cover layer, wherein the cover layer is disposed between the Ohmic-contact layer and the second electrode. 
     
     
         21 . The light emitting diode device of  claim 20 , wherein the cover layer is disposed on the metal reflection layer and extends to a sidewall of the metal reflection layer. 
     
     
         22 . The light emitting diode device of  claim 17 , wherein a portion of the light emitted from the light emitting layer passes through the Ohmic-contact layer as well as the oxide layer and is reflected by the metal reflection layer. 
     
     
         23 . A light emitting diode device, comprising:
 a first-type doping layer;   a second-type doping layer;   a light emitting layer disposed between the first-type doping layer and the second-type doping layer;   an Ohmic-contact layer disposed on the second-type doping layer;   a first electrode disposed on and electrically connected to the first-type doping layer;   a second electrode electrically connected to the Ohmic-contact layer; and   a material stacking layer disposed between the second electrode and the Ohmic-contact layer, the material stacking layer comprising a plurality of first material layers and a plurality of second material layers stacked alternately, wherein light transmittance of the first material layers differs from light transmittance of the second material layers.   
     
     
         24 . The light emitting diode device of  claim 23 , wherein a light transmittance of the Ohmic-contact layer is greater than 90%. 
     
     
         25 . The light emitting diode device of  claim 23  further comprising a metal layer disposed between the second electrode and the Ohmic-contact layer, wherein a portion of the light emitted from the light emitting layer passes through the Ohmic-contact layer and is reflected by the metal layer.