Growth and etching phenomena observed by STM/AFM on pulsed-laser deposited YBa2Cu3O7-δ films

B. Dam*, N. J. Koeman, J. H. Rector, B. Stäuble-Pümpin, U. Poppe, R. Griessen

*Corresponding author for this work

Research output: Contribution to journalArticleScientificpeer-review

37 Citations (Scopus)

Abstract

The surface morphology of pulsed-laser deposited YBa2Cu3O7-δ films is investigated by STM AFM. Instead of spiral growth, a 2D nucleation and growth behaviour is observed. As we find these 2D nuclei also on high-oxygen pressure DC sputtered films grown at a much lower growth rate, we conclude that the supersaturation is not a decisive parameter for the predominance of either growth mode. Instead, we attribute the absence of growth spirals to the non-steady state growth conditions inherent to the pulsed nature of the laser-ablation process. Growth spirals only develop, if a non-vanishing diffusional flow of adatoms towards the step edge is maintained. The number of growth spirals observed on a film is therefore not necessarily a measure for the number of screw dislocations. After wet-etching the films in Br-ethanol, we observe that etch pits are formed consisting of concentric steps. We conclude that these pits are due to repetitive nucleation around linear defects. The etchpit density identified in this way is of the order of 1 per μm2.

Original languageEnglish
Pages (from-to)1-11
Number of pages11
JournalPhysica C: Superconductivity and its Applications
Volume261
Issue number1-2
DOIs
Publication statusPublished - 20 Apr 1996

Fingerprint

Dive into the research topics of 'Growth and etching phenomena observed by STM/AFM on pulsed-laser deposited YBa2Cu3O7-δ films'. Together they form a unique fingerprint.

Cite this