Methods for producing photovoltaic material and device able to exploit high energy photons

Abstract

Methods for producing photovoltaic material and a device able to exploit high energy photons. The photovoltaic material is obtained from a conventional photovoltaic material having a top surface intended to be exposed to photonic radiation, having a built-in P-N junction delimiting an emitter part and a base part and including at least one area or region specifically designed, treated or adapted to absorb high energy or energetic photons, located adjacent or near at least one hetero-interface. This material is subjected to treatments resulting in the formation of at least one semiconductor based metamaterial field or region being created, as a transitional region of the or a hetero-interface, in an area located continuous or proximate to the or an absorption area or region for the energetic photons of the photonic radiation impacting the photovoltaic material.

What is claimed is: 
     
         1 . A photovoltaic device able to exploit high energy UV and visible photons, in addition to IR photons, said device comprising:
 a slab, wafer or chip of P-type or N-type photovoltaic material having a top surface adapted to be exposed to photonic radiation, having a built-in P-N junction delimiting an emitter part and a base part, having front and rear carrier collection and extraction means and comprising at least one area or region forming a layer specifically designed or adapted to absorb high energy or energetic photons and located adjacent or near at least one hetero-interface,   said device also comprising at least one metamaterial region forming a low-energy secondary carrier generation cavity, which is contiguous or proximate to the at least one area or region forming a layer specifically designed or adapted to absorb high energy or energetic photons and subjected to a built-in or applied electrical field having an intensity sufficient to withdraw and move away secondary electrons liberated by primary hot electrons from their initial sites within the at least one metamaterial region, at a speed sufficient to prevent their return into said at least one metamaterial region, thus forming a substructure performing multistage conversion, wherein the metamaterial corresponds to a region comprising an interface of an amorphized and recrystallized material layer which is under local 2D tensile strain and in which divacancies are established and maintained, wherein a density of the divacancies within the at least one metamaterial region is greater than 10 18  divacancies/cm 3 , and a conduction between the metamaterial and an adjacent N-type material has a time constant which is lower than a secondary carrier generation time constant.   
     
     
         2 . The photovoltaic device according to  claim 1 , wherein the front carrier collection and extraction means comprise grooved contact strips penetrating down into at least one amorphous material layer. 
     
     
         3 . The photovoltaic device according to  claim 1 , characterized in that said device comprises a rear face of the slab, wafer or chip, wherein a featured metal layer is designed to perform plasmonic absorption of IR radiations and cooperating with an up-conversion layer and a nanoscale metamaterial field or region located near the rear face. 
     
     
         4 . The photovoltaic device according to  claim 1 , characterized in that said device comprises, on a front surface, an antireflection and light transmitting multilayer nanostructure having a graded-index profile. 
     
     
         5 . The photovoltaic device according to  claim 1 , characterized in that said substructure comprises at least two substructures, at least one located near the top surface and at least one located near a rear face of the photovoltaic material.