Step-flow-growth YBCO films and BST/YBCO bilayer films on vicinal substrates

作者：Wang TS^*; Tian YJ; Peng W; Qi HH; Lin L

来源：Rare Metal Materials and Engineering, 2006, 35(4): 542-545.

• YBa2Cu3O7-delta
• superconducting film
• Ba0.1Sr0.9TiO3/YBa2Cu3O7-delta heterostructure
• epitaxial growth
• pulsed laser deposition

c-axis orientated YBa2Cu3O7-delta film and Ba0.1Sr0.9TiO3/YBa2Cu3O7-delta heterostructure films have been fabricated by pulsed laser deposition on miscut (001) SrTiO3 and (001) LaAlO3 substrates, respectively. Microstructures of the films have been characterized by using X-ray diffraction, scanning electron microscopy and transmission electron microscopy. The results show that the YBa2Cu3O7-delta films grown on 1 degrees similar to 3 degrees miscut substrates display a step-flow crossover to three-dimensional island growths, and on 6 degrees similar to 15 degrees miscut substrates display a complete step flow growth. Perfect heteroepitaxial growth of Ba0.1Sr0.9TiO3/YBa2Cu3O7-delta on 1.2 degrees miscut (001) LaAlO3 has been in-situ achieved. A parallel-plate capacitor configuration is used to measure the capacitance-voltage properties of the Ba0.1Sr0.9TiO3 thin films under a dc bias of +/- 30 V and 1 MHz frequency at 77 K, and the dielectric constant, tenability and figure of merit are found to be 1200, 60%, and 133, respectively, confirming their usefulness for electrically tunable microwave devices at liquid nitrogen temperature.

• 出版日期2006-4
• 单位燕山大学