Preparation of thin film high temperature superconductors

Fundamental issues in preparing high-quality high-T/sub c/ YBa/sub 2/Cu/sub 3/O/sub 7-x/ thin films are addressed. The techniques of inverted cylindrical magneton sputtering and pulsed laser deposition are chosen as successful examples to illustrate how the key problems can be solved. The fabrication of YBa/sub 2/Cu/sub 3/O/sub 7-x//PrBa/sub 2/Cu/sub 3/O/sub 7-x/ superlattices where superconductivity in a single unit cell layer of YBa/sub 2/Cu/sub 3/O/sub 7-x/ was observed demonstrates the state of the art of thin-film deposition of high-T/sub c/ materials. Systematic variations of the deposition parameters result in changes of superconducting and structural properties of the films that correlate with their microwave and infrared characteristics.