Abstract
The initial stages of epitaxial growth of c-axis-perpendicular laser-ablated YBa2Cu3O7- (YBCO) thin films on SrTiO3 and MgO substrates were studied by scanning tunneling microscopy. Surface images of films grown on SrTiO3 with a sequential thickness variation reveal a transition from layerlike to island growth between 8 and 16 unit cells thickness, i.e., YBCO grows on SrTiO3 by a Stranski-Krastanov mechanism. Evidence also points to the existence of a slightly larger critical thickness for the introduction of screw dislocations into those films. In contrast, even the thinnest (8 cells thick) YBCO films were found to grow on MgO by an island mechanism, with screw-growth features clearly present.
Original language | English |
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Pages (from-to) | 7584-7587 |
Number of pages | 4 |
Journal | Physical Review B |
Volume | 45 |
Issue number | 13 |
DOIs | |
State | Published - 1992 |
Externally published | Yes |