Methods for forming superconductor articles and XRD methods for characterizing same

Abstract

A method for forming a superconductive article is disclosed. According to one method, a substrate is provided, the substrate having an aspect ratio of not less than about 1×10 3 , forming a buffer layer overlying the substrate, forming a superconductor layer overlying the buffer layer, and characterizing at least one of the substrate, the buffer layer and the superconductor layer by x-ray diffraction. In this regard, x-ray diffraction is carried out such that data are taken at multiple phi angles. Data acquisition at multiple phi angles permits robust characterization of the film or layer subject to characterization, and such data may be utilized for process control and/or quality control. Additional methods for forming superconductive articles, and for characterizing same with XRD are also disclosed.

1 . A method of forming a superconductive article, comprising the steps of: 
 providing a substrate, the substrate having an aspect ratio of not less than about 1×10 3 ;    forming a buffer layer overlying the substrate;    forming a superconductor layer overlying the buffer layer; and    characterizing at least one of the substrate, the buffer layer and the superconductor layer by x-ray diffraction, wherein x-ray diffraction data are taken at multiple phi angles.    
     
     
         2 . The method of  claim 1 , wherein characterizing is carried out utilizing an x-ray diffraction apparatus, the apparatus comprising an x-ray source and an x-ray detector, wherein x-rays are directed and detected at multiple angles corresponding to the multiple phi angles.  
     
     
         3 . The method of  claim 2 , wherein the substrate and the source and detector are re-positioned relative to each other at said multiple angles corresponding to the multiple phi angles, such that characterizing can be carried out at said multiple phi angles.  
     
     
         4 . The method of  claim 3 , wherein the source and the detector are rotated relative to the substrate.  
     
     
         5 . The method of  claim 4 , wherein the source and the detector are coupled together for coordinated rotation for characterization at said multiple phi angles.  
     
     
         6 . The method of  claim 3 , wherein the substrate is rotated relative to the x-ray source and x-ray detector.  
     
     
         7 . The method of  claim 2 , wherein multiple x-ray sources are provided for characterization at said multiple phi angles.  
     
     
         8 . The method of  claim 2 , wherein multiple x-ray detectors are provided for characterization at said multiple phi angles.  
     
     
         9 . The method of  claim 1 , wherein diffraction data are taken at not fewer than three unique phi angles.  
     
     
         10 . The method of  claim 1 , wherein diffraction data are taken at not fewer than four unique phi angles.  
     
     
         11 . The method of  claim 1 , wherein the detector detects diffracted x-rays from the superconductive article, to provide a pole figure representation of crystal structure of the at least one of the substrate, the buffer layer and the superconductor layer subjected to characterization.  
     
     
         12 . The method of  claim 11 , wherein the pole figure represents the crystal alignment, and a full width at half maximum value is calculated from the pole figure for crystal alignment quantification.  
     
     
         13 . The method of  claim 12 , wherein the at least one of the substrate, buffer layer, and superconductor layer has a crystal structure having a full width half maximum not greater than about 20°.  
     
     
         14 . The method of  claim 13 , wherein the full width at half maximum is not greater than about 10°.  
     
     
         15 . The method of  claim 13 , wherein the superconductor layer has said full width at half maximum value not greater than 20°.  
     
     
         16 . The method of  claim 1 , wherein characterizing is carried out at discrete positions along a length of the article, and the substrate is in a fixed position during characterizing.  
     
     
         17 . The method of  claim 1 , wherein characterizing is carried out continuously along a length of the article, and the substrate continuously moves along its length direction during characterizing.  
     
     
         18 . The method of  claim 1 , wherein the article is in the form of a tape, linearly passing through a characterizing zone in which the x-ray diffraction apparatus is disposed, the tape being routed through the zone by a reel-to-reel apparatus.  
     
     
         19 . The method of  claim 1 , wherein characterizing is carried out on the superconductive layer.  
     
     
         20 . The method of  claim 1 , wherein characterizing is carried out on a biaxially textured surface.  
     
     
         21 . The method of  claim 1 , further comprising forming additional layers overlying the superconductor layer.  
     
     
         22 . The method of  claim 21 , wherein the additional layers include at least one conductive layer in electrical communication with the superconductive layer.  
     
     
         23 . The method of  claim 1 , further comprising utilizing the x-ray diffraction data to alter process conditions for formation of the superconductive article.  
     
     
         24 . The method of  claim 23 , wherein said process conditions are selected from the group consisting of temperature, pressure, gas flow, tape feed rate, precursor material selection, composition, and combinations thereof for formation of at least one of the buffer layer and the superconductor layer.  
     
     
         25 . The method of  claim 1 , further comprising utilizing the x-ray diffraction data to associate crystallography data with said superconductive article.  
     
     
         26 . The method of  claim 25 , wherein said crystallography data are provided to a customer.  
     
     
         27 . The method of  claim 1 , wherein characterizing is carried out on the substrate, prior to formation of the buffer layer and superconductor layer.  
     
     
         28 . The method of  claim 1 , wherein characterizing is carried out on the buffer layer, prior to formation of the superconductor layer.  
     
     
         29 . A superconductive power component comprising multiple superconductive articles in the form of HTS conductive tapes formed according to  claim 1 , wherein the superconductive power component is selected from the group consisting of power cables, power transformers, and power generators.  
     
     
         30 . A method of characterizing a superconductive article, comprising the steps of: 
 providing a superconductive article comprising a substrate, the substrate having an aspect ratio of not less than about 1×10 3 , a buffer layer overlying the substrate, and a superconductor layer overlying the buffer layer; and    characterizing at least one of the substrate, the buffer layer and the superconductor layer by x-ray diffraction, wherein x-ray diffraction data are taken at multiple phi angles.    
     
     
         31 . A method of forming a superconductive article, comprising the steps of: 
 providing a substrate, the substrate having an aspect ratio of not less than about 1×10 3  and having a non-textured crystal structure;    forming a buffer layer overlying the substrate, the buffer layer comprising a biaxially textured film;    forming a superconductor layer overlying the buffer layer; and    characterizing at least one of the buffer layer and the superconductor layer by x-ray diffraction.    
     
     
         32 . The method of  claim 31 , wherein at least a portion of said buffer layer is formed by ion beam assisted deposition (IBAD).  
     
     
         33 . The method of  claim 31 , wherein said substrate comprises a crystalline metal alloy.  
     
     
         34 . The method of  claim 33 , wherein said substrate comprises a nickel alloy.  
     
     
         35 . A method of forming a superconductive article, comprising the steps of: 
 providing a substrate;    forming a buffer layer overlying the substrate;    forming a superconductor layer overlying the buffer layer; and    characterizing at least one of the substrate, the buffer layer and the superconductor layer by x-ray diffraction utilizing an x-ray source having a parallel x-ray beam.    
     
     
         36 . The method of  claim 35 , wherein characterizing is carried out while the article is continuously translated, by an x-ray source and x-ray detector.