T(1)BaCaCuO Thin Films on MgO Substrates for High Frequency Microwave

The preparation of epitaxial T1BaCaCuO films has been demonstrated on only a small number of substrates (LaA1O3 and SrTiO3). At present, LaA1O3 is the only substrate that produces films suitable for microwave applications. However, there are limitations to its use, particularly at high frequency. The two most apparent problems are the high dielectric constant (24.5) and twinning. A near term alternative which can address these problems is MgO. The program proposed is to develop TBCCO films of MgO, which represents the only large area, low dielectric constant, twin-free substrate available at this time. TBCCO films have the highest operating temperature of any films currently available (>100K). If successful, this technology would replace some of the TBCCO material currently grown on LaA1O3 for microwave components at high frequencies and where frequency settability is a key issue.