Micro-Interconnects for Light-Emitting Diodes

Abstract

The present disclosure provides a method of fabricating a light emitting diode (LED) package. The method includes bonding a plurality of separated light emitting diode (LED) dies to a substrate, wherein each of the plurality of separated LED dies includes an n-doped layer, a quantum well active layer, and a p-doped layer; depositing an isolation layer over the plurality of separated LED dies and the substrate; etching the isolation layer to form a plurality of via openings to expose portions of each LED die and portions of the substrate; forming electrical interconnects over the isolation layer and inside the plurality of via openings to electrically connect between one of the doped layers of each LED die and the substrate; and dicing the plurality of separated LED dies and the substrate into a plurality of LED packages.

What is claimed is: 
     
         1 . A light-emitting diode (LED) device, comprising:
 a substrate having a first side and a second side opposite the first side;   a conductive element extending through the substrate from the first side to the second side;   an LED die disposed over the first side of the substrate;   an electrically-insulating layer disposed over the LED die, the electrically-insulating layer containing an opening; and   an interconnect feature disposed over the substrate and partially over the LED die, wherein a first end of the interconnect feature is electrically coupled to the LED die through the opening of the electrically-insulating layer, and a second end of the interconnect feature is electrically coupled to the conductive element, the second end being opposite the first end.   
     
     
         2 . The LED device of  claim 1 , wherein the electrically-insulating layer is disposed on top and side surfaces of the LED die. 
     
     
         3 . The LED device of  claim 1 , wherein portions of the interconnect feature other than the first end are separated from the LED die by the electrically-insulating layer. 
     
     
         4 . The LED device of  claim 1 , further comprising a phosphor layer disposed over the LED die, wherein portions of the interconnect feature and the electrically-insulating layer are disposed below the phosphor layer. 
     
     
         5 . The LED device of  claim 1 , further comprising a lens disposed over the phosphor layer. 
     
     
         6 . The LED device of  claim 1 , wherein the interconnect feature is transparent. 
     
     
         7 . The LED device of  claim 1 , wherein the substrate is a packaging substrate. 
     
     
         8 . The LED device of  claim 7 , wherein the conductive element is a through-silicon-via (TSV). 
     
     
         9 . The LED device of  claim 8 , wherein the TSV is a first TSV, and further comprising:
 a second TSV extending through the packaging substrate from the first side to the second side; and   a first conductive pad and a second conductive pad each disposed on the first side of the substrate, the first and second conductive pads being electrically coupled to the first and second TSVs, respectively.   
     
     
         10 . The LED device of  claim 9 , wherein:
 the interconnect feature is partially disposed on the first conductive pad; and   the LED die is disposed on the second conductive pad.   
     
     
         11 . The LED device of  claim 9 , further comprising a third conductive pad and a fourth conductive pad each disposed on the second side of the substrate, the third and fourth conductive pads being electrically coupled to the first and second conductive pads through the first and second TSVs, respectively. 
     
     
         12 . The LED device of  claim 11 , wherein:
 the LED die includes a first semiconductor layer, a second semiconductor layer having a different type of conductivity than the first semiconductor layer, and a light-emitting layer being disposed between the first and second semiconductor layers;   the first semiconductor layer is electrically coupled to the third conductive pad at least in part through the first TSV, the first conductive pad, and the interconnect feature; and   the second semiconductor layer is electrically coupled to the fourth conductive pad at least in part through the second TSV and the second conductive pad.   
     
     
         13 . The LED device of  claim 12 , wherein the LED die includes a carrier substrate, the carrier substrate being disposed between the second semiconductor layer and the second conductive pad. 
     
     
         14 . A light-emitting diode (LED) device, comprising:
 a packaging substrate having a front side and a back side;   a first conductive pad and a second conductive pad each disposed on the front side of the packaging substrate;   a third conductive pad and a fourth conductive pad each disposed on the back side of the packaging substrate;   a first through-silicon-via (TSV) and a second TSV disposed in the packaging substrate, wherein the first and third conductive pads are electrically coupled together by the first TSV, and wherein the second and fourth conductive pads are electrically coupled together by the second TSV;   an LED die disposed on the second conductive pad;   an isolation layer disposed on top and side surfaces of the LED die, the isolation layer including an opening that exposes a portion of the top surface of the LED die; and   a conductive layer partially disposed on top and side surfaces of the isolation layer, wherein the conductive layer has opposite first and second distal ends, the first distal end being in physical contact with the LED die through the opening, and the second distal end of the conductive layer being in physical contact with the first conductive pad.   
     
     
         15 . The LED device of  claim 14 , further comprising:
 a phosphor layer disposed over the LED die and over portions of the conductive layer and the isolation layer; and   a lens disposed over the phosphor layer.   
     
     
         16 . The LED device of  claim 14 , wherein the conductive layer is transparent. 
     
     
         17 . The LED device of  claim 14 , wherein:
 the LED die includes oppositely-doped first and second semiconductor layers and a light-emitting layer disposed between the first and second semiconductor layers;   the first semiconductor layer is electrically coupled to the third conductive pad at least in part through the first TSV, the first conductive pad, and the conductive layer; and   the second semiconductor layer is electrically coupled to the fourth conductive pad at least in part through the second TSV and the second conductive pad.   
     
     
         18 . The LED device of  claim 17 , wherein the LED die includes a carrier substrate, the carrier substrate being disposed between the second semiconductor layer and the second conductive pad. 
     
     
         19 . A light emitting diode (LED) device comprising:
 a substrate including a bonding contact and an electrode;   an LED die bonded to the substrate through the bonding contact;   an isolation layer disposed over the LED die and the substrate, wherein the isolation layer includes a plurality of via openings to expose portions of the LED die and the electrode of the substrate; and   an interconnect layer deposited over the isolation layer and the plurality of via openings to electrically connect the LED die to the electrode of the substrate.   
     
     
         20 . The device of  claim 19 , wherein the bonding contact and the electrode are configured to electrically couple through a through-silicon via (TSV) embedded in the substrate.