High brightness light emitting device with small size

Abstract

This application describes a light emitting device or an assembly of light emitting devices. In the completed device, an LED at least partially overlies a thin film transistor and a reflective layer is disposed between the LED and the thin film transistor. Methods to fabricate such devices and assemblies of devices are also described.

What is claimed is: 
     
         1 . A light emitting device comprising:
 a thin film transistor;   an LED having a surface area, wherein the LED at least partially overlies the transistor and wherein the LED comprises GaP, AlGaAs, GaAsP, AlGaP, GaInP, InGaN, AlGaN, AlN, InN, or InP;   a reflective layer disposed between the thin film transistor and the LED;   and a backboard comprising an interposer, wherein the interposer comprises a plurality of metal wires.   
     
     
         2 . The light emitting device of  claim 1 , further comprising an interconnect extending through the reflective layer that electrically connects the LED and the thin film transistor. 
     
     
         3 . The light emitting device of  claim 1 , wherein the reflective layer comprises a Bragg reflector. 
     
     
         4 . The light emitting device of  claim 2 , wherein the interconnect comprises indium tin oxide, fluorine tin oxide, aluminum zinc oxide, metallic nanoparticles, carbon nanotubes, graphene, or conductive polymers. 
     
     
         5 . The light emitting device of  claim 1 , further comprising a transparent conductive layer in electrical contact with the LED. 
     
     
         6 . The light emitting device of  claim 5 , wherein the transparent conductive layer comprises indium tin oxide, fluorine tin oxide, aluminum zinc oxide, metallic nanoparticles, carbon nanotubes, graphene, or conductive polymers. 
     
     
         7 . The light emitting device of  claim 1 , wherein the surface area of the LED is 40,000 square microns or less. 
     
     
         8 . The light emitting device of  claim 1 , wherein the surface area of the LED is 1,000 square microns or less. 
     
     
         9 . The light emitting device of  claim 1 , wherein the surface area of the LED is 100 square microns or less. 
     
     
         10 . (canceled) 
     
     
         11 . (canceled) 
     
     
         12 . An assembly of light emitting devices comprising:
 a plurality of thin film transistors;   a plurality of LEDs, wherein each LED of the plurality of LEDs has a surface area and wherein each LED comprises GaP, AlGaAs, GaAsP, AlGaP, GaInP, InGaN, AlGaN, AlN, InN, or InP, and each LED of the plurality of LEDs at least partially overlies a thin film transistor of the plurality of thin film transistors;   a reflective layer, wherein the reflective layer is disposed between an LED of the plurality of LEDs and a thin film transistor of the plurality of thin film transistors; and   and a backboard comprising an interposer, wherein the interposer comprises a plurality of metal wires.   
     
     
         13 . The assembly of light emitting devices of  claim 12 , further comprising a plurality of interconnects, wherein each interconnect is electrically connected to an LED of the plurality of LEDs and a thin film transistor of the plurality of thin film transistors. 
     
     
         14 . The assembly of light emitting devices of  claim 12 , further comprising a transparent conductive layer electrically connected to the plurality of LEDs. 
     
     
         15 . The assembly of light emitting devices of  claim 14 , wherein the transparent conductive layer comprises indium tin oxide, fluorine tin oxide, aluminum zinc oxide, metallic nanoparticles, carbon nanotubes, graphene, or conductive polymers. 
     
     
         16 . The assembly of light emitting devices of  claim 12 , further comprising a plurality of wavelength-converting layers. 
     
     
         17 . The assembly of light emitting devices of  claim 16 , wherein the plurality of wavelength-converting layers comprises phosphor particles or quantum dots. 
     
     
         18 . The assembly of light emitting devices of  claim 12 , wherein the reflective layer comprises a Bragg reflector. 
     
     
         19 . The assembly of light emitting devices of  claim 12 , further comprising a plurality of side reflectors, wherein the side reflectors are disposed between adjacent LEDs of the plurality of LEDs and prevent light from adjacent LEDs in the plurality of LEDs from interfering with one another. 
     
     
         20 . (canceled) 
     
     
         21 . The assembly of light emitting devices of  claim 12 , wherein the surface area of at least one LED of the plurality of LEDs is 40,000 square microns or less. 
     
     
         22 . The assembly of light emitting devices of  claim 12 , wherein the surface area of at least one LED of the plurality of LEDs is 1,000 square microns or less. 
     
     
         23 . The assembly of light emitting devices of  claim 12 , wherein the surface area of at least one LED of the plurality of LEDs is 100 square microns or less.