Temperature-dependent vacancy formation during the growth of Cu on Cu(001)

Ab initioinvestigation of defect formation at ZrO2-CeO2interfaces

“…Since the ion mobility in these lattice structures involves the presence of a number of intrinsic defects (oxygen vacancies), it is mandatory to investigate any physical or chemical process able to affect their concentration. Above all, the strain at the interface, induced by the lattice mismatch between the two materials, seems to play a key role in triggering the formation of a preferential migration channel for the ionic transport and in affecting the defect formation energy, as also pointed out by Botez et al 14 In this work we use ab initio calculations within the density functional theory (DFT) framework to investigate the structure of two CeO 2 -ZrO 2 interfaces and how they affect the formation energies of intrinsic and extrinsic defects. In particular, we analyze ZrO 2 -CeO 2 junctions built along the (100) direction, as in the experiments by Sanna et al, 11 and along the (111) direction.…”

Vacancy trapping and annealing in noble-metal films grown at low temperature

“…A detailed analysis of the different surfaces will be reported elsewhere. 6,7 We suggest that vacancy incorporation is likely to be ubiquitous among many homoepitaxial growth systems, with important consequences for the surface morphology, i.e., the onset of vacancy incorporation occurs in the same temperature range where substantial changes in the growing surface have been observed for all three systems studied. 3,6,8 -10 The measurements on Ag/Ag͑001͒ were carried out on the Midwest Universities Collaborative Access Team ͑CAT͒ beamline at the Advanced Photon Source, while Ag/ Ag͑111͒ and Cu/Cu͑001͒ were measured using the SUNY X3B2 beamline at the National Synchrotron Light Source.…”

Surface and structural disorder in MBE and sputtering deposited Cu thin films revealed by X-ray measurements

“…Moreover, in order to avoid interdiffusion between different layers of the same device, which in the most common cases is a multilayered structure of different elements, the Cu deposition should be performed at low or at room substrate temperature. This gives rise to textured rather than epitaxial growth confirming that a control of grain dimensions and surface roughness is of fundamental importance when fabricating layered structures [2,3,7,10]. Because the deposition time is one of the decisive parameters in the electronic industry, a study of the surface quality of Cu thin films on Si substrates deposited at different rates can give additional indications about the best growth technique to adopt.…”

“…A renewed interest in Cu thin films deposited with different techniques has been recently observed [1][2][3][4][5][6][7][8][9][10][11] because of the possibility of employing this material for interconnections, cap layers or contacts in the microelectronic industry. Due to the low cost, Cu is replacing Al in the fabrication of electronic devices.…”

“…Cu thin films can be obtained with different methods. Sputtering [1][2][3][4][5], electroplating [6][7][8][9] and thermal evaporation [10,11] are the most commonly used deposition techniques even though the structural and electrical quality of the films strongly depend on the deposition process. In particular, if one is interested in the purity of the final product, thermal evaporation in ultra-high vacuum conditions should be used.…”