High temperature superconductivity materials will permit development of a wide variety of electronic devices with decreased power requirements. This program will create large single crystallites of 1-2-3 compound superconductor material; increased current carrying capacity of large single crystals will allow a practical use of high Tc materials. The objective of Phase I of this program will be to enlarge the size of microscopic crystallites to a size such that they may be cut out of ceramic material and used as an interconnection in a circuit device. The procedure used to increase the size of single crystal form of high Tc material will take advantage of initial formation of crystallites at 950 degrees centigrade. Solid phase epitaxial growth of larger crystallites will be performed by developing a temperature gradient in a tube furnace. A very narrow zone (mm long) will be created at 950 degrees centigrade while the remainder of the tube furnace will be maintained at approximately 850 degrees centigrade. This narrow zone will be moved slowly along the length of the material to permit solid phase epitaxial formation of larger crystallites. The objective of obtaining larger crystallites will be attained by studying the mechanisms involved in creation of oriented crystallites in the heat treatment processing of ceramic materials.
