Roll-to-roll fabricated light sheet and encapsulated semiconductor circuit devices

Abstract

A light active sheet, comprising a first substrate flexible sheet having an electrically conductive surface, a second transparent substrate flexible sheet having a transparent conductive layer disposed thereon, an electrically insulative adhesive flexible sheet and light active semiconductor elements fixed to the electrically insulative adhesive sheet. The light active semiconductor elements each have an n-side and a p-side. The electrically insulative adhesive sheet having the light active semiconductor elements fixed thereon is inserted between the electrically conductive surface and the transparent conductive layer to form a lamination which is activated so that the electrically insulative adhesive electrically insulates and binds the second substrate sheet to the first substrate sheet. One of the n-side and p-side are in electrical communication with the transparent conductive layer and the other of the n-side or the p-side is in electrical communication with the electrically conductive surface.

1 ) A light active sheet, comprising:
 a first substrate flexible sheet having an electrically conductive surface;   a second transparent substrate flexible sheet having a transparent conductive layer disposed thereon;   an electrically insulative adhesive flexible sheet;   light active semiconductor elements fixed to the electrically insulative adhesive sheet, said light active semiconductor elements each having an n-side and a p-side, the electrically insulative adhesive sheet having the light active semiconductor elements fixed thereon being inserted between the electrically conductive surface and the transparent conductive layer to form a lamination and activated so that the electrically insulative adhesive electrically insulates and binds the second substrate sheet to the first substrate sheet so that one of said n-side or said p-side of the light active semiconductor elements is in electrical communication with the transparent conductive layer of the second substrate sheet and so that the other of said n-side or said p-side of each said light active semiconductor element is in electrical communication with the electrically conductive surface of the first substrate sheet to form a light active device.   
     
     
         2 ) A light active sheet according to  claim 1 ;
 wherein the first substrate, the electrically insulative adhesive and the second substrate are provided as respective rolls of material; and   the step of inserting comprising bringing the first substrate, the electrically insulative adhesive and the second substrate together in a continuous roll fabrication process.   
     
     
         3 ) A light active sheet according to  claim 1 ; wherein the electrically insulative adhesive comprises a hotmelt material activatable by applying heat and pressure to the lamination to soften the hotmelt material. 
     
     
         4 ) A light active sheet according to  claim 1 ; wherein the adhesive is activatable by at least one of solvent action, evaporation, catalytic reaction and radiation curing. 
     
     
         5 ) A light active sheet according to  claim 1 ; wherein the light active semiconductor elements are light emitting diode die. 
     
     
         6 ) A light active sheet according to  claim 1 ; wherein the light active semiconductor elements are light-to-energy devices. 
     
     
         7 ) A light active sheet according to  claim 1 ; wherein a first portion of the light active semiconductor elements emit a first wavelength of radiation and a second portion of the light active semiconductor elements emit a second wavelength of radiation. 
     
     
         8 ) A light active sheet according to  claim 1 ; wherein the electrically insulative adhesive comprises a hotmelt sheet; and the light active semiconductor elements are embedded into the hotmelt sheet before forming the lamination. 
     
     
         9 ) A light active sheet according to  claim 1 ; wherein the light active semiconductor elements are formed into a predetermined pattern. 
     
     
         10 ) A light active sheet according to  claim 9 ; wherein the light active semiconductor elements are formed into the predetermined pattern by electrostatically attracting a plurality of said light active semiconductor elements on a transfer member and transferring the predetermined pattern onto the insulative adhesive. 
     
     
         11 ) A method of making a light active sheet according to  claim 9 ; wherein the light active semiconductor elements are formed into the predetermined pattern by magnetically attracting a plurality of said light active semiconductor elements on a transfer member and transferring the predetermined pattern onto the insulative adhesive. 
     
     
         12 ) A light active sheet according to  claim 1 ; wherein the transparent conductive layer comprises a transparent conductive material formed as conductive light transmissive connecting lands, each said land for connecting with a respective light active semiconductor. 
     
     
         13 ) A light active sheet according to  claim 12 ; further comprising a relatively higher conducting line pattern formed on at least one of the second substrate and the first substrate for providing a relatively lower path of resistance from a power supply source to each said light active semiconductor element. 
     
     
         14 ) A light active sheet according to  claim 1 ; wherein the electrically conductive surface and the electrically conductive pattern comprise a respective x and y wiring grid for selectively addressing individual said light active semiconductor elements for forming a display. 
     
     
         15 ) A light active sheet according to  claim 1 ; further comprising a phosphor provided in the lamination, said phosphor being optically stimulated by a radiation emission of a first wavelength from the light active semiconductor element to emit light of a second wavelength. 
     
     
         16 ) A light active sheet according to  claim 1 ; further comprising at least one additional semiconductor element, each of said additional semiconductor elements having a first conductor, a second conductor and a middle conductor region disposed therebetween; and wherein said electrically insulative adhesive includes at least one electrically conductive portion for making an electrical connection with said middle conductor region. 
     
     
         17 ) A light active sheet according to  claim 16 ; wherein at least one of said at least one additional semiconductor elements is an npn type semiconductor element.