Growth by MOMBE of c-axis superconducting YBCO thin films on different substrates: in situ RHEED monitoring of the growth

MOMBE Growth of ${\rm YBa}_{2}{\rm Cu}_{3}{\rm O}_{7}$ Thin Films With c-Axis, a-Axis and (103/110) Orientations on ${\rm SrTiO}_{3}$ Substrate

“…RHEED patterns taken during growth of the c-axis thin film when using the ( Fig. 1(a)) are similar to those for the source, and the streaky vs. spot behavior of the patterns observed for the source on substrate in [10] are similar as well. Although we obtained by the MOMBE c-axis thin films at lower growth temperatures than, e.g., for MOCVD growth using [1], the use of or in MOMBE has not produced any distinct changes in the growth and quality of the c-axis films.…”

“…1(b) and 1(c)). Patterns for the a-axis and c-axis oriented films show streaky features indicative of smooth film surfaces and suggest a 2D type growth [10], [19]. The difference is that for the a-axis film, two extra lines located at 1/3 and 2/3 the distance between the high intensity lines of the film (that also match the lines of the substrate) are observed ( Fig.…”

“…For example, in both situations, (001)Y123 film showed a metallic behavior in the normal state and a sharp transition with zero-resistance critical temperature of 82-85 K for repeated experiments (see Fig. 4(a) for the (001)Y123 film prepared using and data from [10] for the growth of films using ). RHEED patterns taken during growth of the c-axis thin film when using the ( Fig.…”

“…Thin (001), (100/010) and (103/110) oriented films (Fig. 2) with ICP cation ratios , In our previous work [6], [10] on MOMBE growth we used instead of . The two precursor source materials have shown similar behaviors.…”

“…Before deposition, the substrates were heated to 300 in ozone. RHEED indicated the process of cleaning of the substrate surface [10]. AFM shown in Figs.…”