Crystal growth of YBa2Cu3O7−x at the MgO (100) surface steps

✍ Scribed by Hiromi Takahashi; Yuji Aoki; Toshio Usui; Rainer Fromknecht; Tadataka Morishita; Shoji Tanaka

• Publisher: Elsevier Science
• Year: 1991
• Tongue: English
• Weight: 951 KB
• Volume: 175
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/0921-4534(91)90612-3

✦ Synopsis

We have investigated the crystal growth of YBazCu,07_, thin films on MgO( 100) with particular interest on the growth at substrate surface steps. Films were deposited by the activated reactive co-evaporation method at a substrate temperature of 550°C. Cross-sectional transmission electron microscopy was used to study the microstructure.

The film is composed primarily of grains oriented with the c-axis normal to the substrate surface and a small volume fraction of grains with the a-axis normal to the substrate surface. This a-axis oriented grain grows at the substrate surface steps. Furthermore, a very small fraction of off-axis grain grows at the substrate surface steps or microcracks. At both sides of the grain at the edge of an 8 A step, cationic stacking is matched above the step. Many microstructure differences are observed at the substrate surface steps.