GRAIN BOUNDARY JOSEPHSON ELEMENT AND ITS MANUFACTURE

PURPOSE:To obtain a uniform crystal grain boundary with an improved coherency and less lattice distortion by controlling a grain boundary surface orientation so that it has an improved coherency in a Josephson junction utilizing the crystal grain boundary. CONSTITUTION:When two two-dimensional tetragonal lattices use a certain lattice point as an overlapped origin and then are overlapped while they are rotated by 36.8 degrees in reference to the point, the lattice point indicated by a circle is an approximate corresponding lattice point created by overlapping. Assuming that an inclination grain boundary is the overlapping of two crystal lattices and then re-proximity approximate corresponding lattice points constituting the crystal grain boundary are constituted of (x, y)1 and (m, n)2, the SIGMAvalue in that case is expressed by either x ; y or m +n . When the coherency of the interface is considered according to the size of the SIGMA value, the fact that the SIGMA value is small means that the instance between the approximate corresponding lattice points in the interface is short, thus achieving an interface with improved coherency.