Structure and composition of the surfaces of sputtered YBa2Cu3O7−δ thin films — an XPS and LEED study

Surface Cleaning and Adsorbate Layer Formation: Dual Role of Alkylamines in the Formation of Self-Assembled Monolayers on Cuprate Superconductors

“…This degradation layer is characterized by a broad multiplet absorption in the Y(3d) region, the BaCO 3 signature in the Ba(3d5/2) region (i.e., the lower energy humps on the main peaks), and a CO 3 2- signature in the O(1s) region (i.e., ∼527 eV). These spectral signatures supports the presence of a degradation layer, in good agreement with the prior literature for similarly treated samples. − Quite interestingly, treatment of the “dirty” YBa 2 Cu 3 O 7 samples with a 2 mM solution of octadecylamine, butylamine, or hexylamine for 12 h leads to a dramatic improvement in the XPS signature for the cuprate powder, film, and pellet samples (Figure , solid curves). The presence of a clean exterior is noted by the doublet-like feature in the Y(3d) region, matching closely the pristine case that was prepared and evaluated in situ. − In addition, the amine exposure serves, for the most part, to eliminate the BaCO 3 surface layers, as evidenced by the clean Ba(3d5/2), Ba(3d3/2), and O(1s) transitions.…”

“…These spectral signatures supports the presence of a degradation layer, in good agreement with the prior literature for similarly treated samples. − Quite interestingly, treatment of the “dirty” YBa 2 Cu 3 O 7 samples with a 2 mM solution of octadecylamine, butylamine, or hexylamine for 12 h leads to a dramatic improvement in the XPS signature for the cuprate powder, film, and pellet samples (Figure , solid curves). The presence of a clean exterior is noted by the doublet-like feature in the Y(3d) region, matching closely the pristine case that was prepared and evaluated in situ. − In addition, the amine exposure serves, for the most part, to eliminate the BaCO 3 surface layers, as evidenced by the clean Ba(3d5/2), Ba(3d3/2), and O(1s) transitions. Finally, the XPS signature of the adsorbed amine reagent is found in the N(1s) region of the spectra that was absent in the untreated samples.…”

“…These spectral signatures supports the presence of a degradation layer, in good agreement with the prior literature for similarly treated samples. [17][18][19] Quite interestingly, treatment of the "dirty" YBa 2 -Cu 3 O 7 samples with a 2 mM solution of octadecylamine, butylamine, or hexylamine for 12 h leads to a dramatic improvement in the XPS signature for the cuprate powder, film, and pellet samples (Figure 2, solid curves). The presence of a clean exterior is noted by the doublet-like feature in the Y(3d) region, matching closely the pristine case that was prepared and evaluated in situ.…”

Structure of ultrathin heteroepitaxial superconductingYBa2Cu3O7−xfilms

“…Surface superstructures for YBCO grown on STO or for structurally very similar Re Ba 2 Cu 3 O 7−x ͑Re = rare-earth ion͒ films have been variously reported. [18][19][20][21] No indication of any superstructures could be found on our samples with intensities larger than 0.01 of the weakest parts of the CTR signal.…”

Preparation and characterization of epitaxial gold films deposited on mica by direct current magnetron sputtering

“…17 As substrate material Green Muscovite Mica sheets from Asheville Schoonmaker ͑Newport News, VA͒ were cleaved in air and transferred to the sputter chamber via load lock. 17 As substrate material Green Muscovite Mica sheets from Asheville Schoonmaker ͑Newport News, VA͒ were cleaved in air and transferred to the sputter chamber via load lock.…”