Depositing Calcium Fluoride Template Layers for Solar Cells

Abstract

A biaxially textured crystalline layer formed on a substrate is provided. The biaxially textured crystalline layer includes an oriented CaF 2 crystalline layer having crystalline grains oriented in both in-plane and out-of-plane directions, where the out-of-plane orientation is a (111) out-of-plane orientation. The oriented CaF 2 crystalline layer is disposed for growth of a subsequent epitaxial layer and the CaF 2 crystalline layer comprises an IBAD CaF 2 layer. The biaxially textured CaF 2 layer can be used in a photovoltaic cell, an electronic or optoelectronic device, an integrated circuit, an optical sensor, or a magnetic device.

1 . A biaxially textured crystalline layer comprising an oriented CaF 2  crystalline layer formed on a substrate, wherein said oriented CaF 2  crystalline layer comprises a (111) out-of-plane orientation. 
     
     
         2 . The biaxially textured crystalline layer of  claim 1 , wherein said oriented CaF 2  crystalline layer is disposed for growth of a subsequent epitaxial layer. 
     
     
         3 . The biaxially textured crystalline layer of  claim 1 , wherein said oriented CaF 2  crystalline layer comprises an IBAD CaF 2  layer. 
     
     
         4 . The biaxially textured crystalline layer of  claim 1 , wherein said substrate is selected from the group consisting of glass, metal, ceramic, polymer, Si, Ge, YSZ, Al 2 O 3 , Cu, Au, Ag, Pt, Ir, GaAs, GaP, AlAs, ZnSe, CdS, InAs, InGaAs AlGaAs, GaSb, CdSe, AlSb, ZnTe, InGaAs, InP, fused quartz, SiO 2 , SiN, glass, plastics, and metal foils. 
     
     
         5 . The biaxially textured crystalline layer of  claim 1 , wherein said subsequent epitaxial layer is selected from the group consisting of CaF 2 , BaF 2 , CdF 2 , SrF 2 , Si, Ge, YSZ, Al 2 O 3 , Cu, Au, Ag, Pt, Ir, GaAs, GaP, AlAs, ZnSe, CdS, InP, InAs, InGaAs AlGaAs, GaSb, CdSe, AlSb, ZnTe, and InGaAs. 
     
     
         6 . The biaxially textured crystalline layer of  claim 1 , wherein said oriented CaF 2  crystalline layer contains added materials to form an alloyed CaF 2  crystalline layer. 
     
     
         7 . The alloyed CaF 2  crystalline layer of  claim 6 , wherein said added materials are selected from the group consisting of BaF 2 , SrF 2 , and CdF 2 . 
     
     
         8 . The alloyed CaF 2  crystalline layer of  claim 6 , wherein said alloyed CaF 2  crystalline layer comprises a lattice constant in the range between 5.39 Angstroms and 6.2 Angstroms. 
     
     
         9 . The alloyed CaF 2  crystalline layer of  claim 6 , wherein said alloyed CaF 2  crystalline layer has a composition that is up to 99.999% alloying material. 
     
     
         10 . The biaxially textured crystalline layer of  claim 1 , wherein said oriented CaF 2  crystalline layer is doped with Europium.