Growth of (Cu,C)Ba2CuOy thin films by molecular-beam epitaxy

✍ Scribed by H. Shibata; S. Karimoto; T. Makimoto

• Publisher: Elsevier Science
• Year: 2007
• Tongue: English
• Weight: 158 KB
• Volume: 463-465
• Category: Article
• ISSN: 0921-4534
• DOI: 10.1016/j.physc.2006.12.022

✦ Synopsis

We report the growth of (Cu,C)Ba 2 CuO y thin films by molecular-beam epitaxy (MBE). The c-axis oriented film is obtained with a = 3.959 A ˚and c = 8.140 A ˚. The T c values of the film on an NdGaO 3 substrate are T c (on) $ 35 K and T c (zero) $ 18 K. The T c (on) is increased to 70 K for a 12 nm-thick film deposited on an infinite-layer CaCuO 2 buffer layer. This suggests that the layer-by-layer growth method using (Cu,C)Ba 2 CuO y and [CaCuO 2 ] nÀ1 is a promising way to obtain higher member (Cu,C)Ba 2 Ca nÀ1 Cu n O y (n P 2) thin films with a higher T c . We also find that the Ba-Cu-O phase with c $ 4.0 A ˚, which is known as the 'infinite-layer BaCuO 2 ' phase, can be obtained only in a slightly CO 2 atmosphere. This means that the phase contains carbon in its structure.