Micro light emitting diode array and manufacturing method thereof

Abstract

An embodiment of the present invention provides a micro light emitting diode (LED) array and its manufacturing method. The micro-LED includes a substrate, an epitaxial layer formed on the substrate, and a conversion film formed on the epitaxial layer. Pixels can be defined through lithography, and the pixel size can be very small. This method is characterized in that a mass transfer is not required.

What is claimed is: 
     
         1 . A micro light emitting diode array, comprising:
 a substrate;   a plurality of epitaxial layers in direct contact with a surface of the substrate for emitting a first light having a first color;   a plurality of first conversion films formed on a plurality of exposed first upper surfaces of the plurality of epitaxial layers, each of the plurality of first conversion films being in direct contact with respective one of the plurality of exposed first upper surfaces; and   a plurality of second conversion films formed on a plurality of exposed second upper surfaces of the plurality of epitaxial layers, each of the plurality of second conversion films being in direct contact with respective one of the plurality of exposed second upper surfaces;   wherein each of the first conversion film and each of the second conversion film comprise:   one or more light-emitting materials, each light-emitting material absorbing the first light and then re-emitting another light with a color different from the first color;   a host that eliminates grain boundaries and light scattering of the one or more light-emitting materials after the first conversion films or the second conversion films are formed.   
     
     
         2 . The micro light emitting diode array as recited in  claim 1 , wherein each of the epitaxial layers defines a pixel having a size equal to or less than 15 μm. 
     
     
         3 . The micro light emitting diode array as recited in  claim 1 , further comprising a plurality of third conversion films respectively formed on a plurality of third upper surfaces of the epitaxial layers. 
     
     
         4 . The micro light emitting diode array as recited in  claim 1 , wherein the one or more light-emitting materials comprise organic dyes made of non-rare earth elements, and the host keeps the polarity of the organic dyes and hence keeps absorption and radiation wavelength range as in the liquid form. 
     
     
         5 . The micro light emitting diode array as recited in  claim 4 , wherein the organic dyes comprise C545T or DCJTB. 
     
     
         6 . The micro light emitting diode array as recited in  claim 1 , wherein the host comprises a polymer. 
     
     
         7 . The light-emitting thin film as recited in  claim 6 , wherein the polymer comprises polyvinylpyrrolidone (PVP), epoxy, polymethylmethacrylate (PMMA), or polydimethylsiloxane (PDMS).