The Microstructure and Electromigration behaviour of Al-0.35%Pd Interconnects

1994 ◽  
Vol 338 ◽  
Author(s):  
L.J. Elliott ◽  
D.C. Paine ◽  
J.H. Rose
Keyword(s):  
Grain Size ◽  
Grain Boundary ◽  
Critical Current ◽  
Current Density ◽  
Current Effect ◽  
Material Microstructure ◽  
Detailed Evaluation

ABSTRACTAl-Pd alloys have shown promise for improved IC interconnect manufacturability and reliability. However, there has been little detailed evaluation of microstructure and conductor failure reported for this material. Microstructure and electromigration behaviour of Al-0.35%Pd unpassivated interconnect was studied on films deposited at 250°C or 450°C and patterned into test structures of varying width. Samples were electrically stressed to failure at l×106A/cm2 or 2×106A/cm2. At 450°C, AlPdx precipitates form while at 250°C, palladium remains in solution and a larger grain size is obtained. Slit voids were found in 1μm and 3μm wide lines, though only in the finer lines were the failures transgranular. A very large increase in lifetime of 1μm wide lines with a decrease in current density from 2×106A/cm2 to l×106A/cm2 suggests a critical current effect due to grain boundary clusters in the these lines.

Facet Topography and Dislocation Structure as a Possible Source for Electrical Heterogeneity in [001] TILT Bicrystals of YBa2Cu3O7-δ

1996 ◽  
Vol 54 ◽  
pp. 338-339
Author(s):  
I-Fei Tsu ◽  
D.L. Kaiser ◽  
S.E. Babcock
Keyword(s):  
Grain Boundary ◽  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
Electromagnetic Properties ◽  
Length Scale ◽  
Density Values ◽  
Current Densities ◽  
Applied Fields ◽  
A Current

A current theme in the study of the critical current density behavior of YBa2Cu3O7-δ (YBCO) grain boundaries is that their electromagnetic properties are heterogeneous on various length scales ranging from 10s of microns to ˜ 1 Å. Recently, combined electromagnetic and TEM studies on four flux-grown bicrystals have demonstrated a direct correlation between the length scale of the boundaries’ saw-tooth facet configurations and the apparent length scale of the electrical heterogeneity. In that work, enhanced critical current densities are observed at applied fields where the facet period is commensurate with the spacing of the Abrikosov flux vortices which must be pinned if higher critical current density values are recorded. To understand the microstructural origin of the flux pinning, the grain boundary topography and grain boundary dislocation (GBD) network structure of [001] tilt YBCO bicrystals were studied by TEM and HRTEM.

Study on the High Speed Jet-Electrode Position Ni-P Alloy

2013 ◽  
Vol 567 ◽  
pp. 39-44
Author(s):  
Ying Wang ◽  
Min Kang ◽  
Yong Yang ◽  
Xiu Qing Fu
Keyword(s):  
Grain Size ◽  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
High Speed ◽  
Electrode Position ◽  
Stirring Intensity

The high speed jet-electrodepositing equipment was used to prepare Ni-P alloy in substrate of 45 steel. The influences of current density on depositing rate, hardness of deposit and microstructure of Ni-P alloy were studied, and the comparation with that of conventional electroplating were studied. The results show that with the increase of stirring intensity of the electrolyte, the thickness of diffused layer decreases, the critical current density increases, and then the depositing rates increase to 69.82/min. A linear increasing of the depositing rate with the increase of current density is observed, and it refines grain size obviously. Deposit hardness up to 679HV.

Increased grain boundary critical current density Jcgb by Pr-doping in pulsed laser–deposited Y1−xPrxBCO thin films

2011 ◽  
Vol 110 (11) ◽  
pp. 113905 ◽  
Author(s):  
M. Irjala ◽  
H. Huhtinen ◽  
V. P. S. Awana ◽  
M. Falter ◽  
P. Paturi
Keyword(s):  
Thin Films ◽  
Grain Boundary ◽  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
Pulsed Laser

Grain Boundary Structure and Properties of High-Tc Superconductors

1992 ◽  
Vol 275 ◽  
Author(s):  
K. Jagannadham ◽  
J. Narayan
Keyword(s):  
Grain Boundary ◽  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
Boundary Effects ◽  
Boundary Structure ◽  
Excess Charge ◽  
High Tc Superconductors ◽  
High Tc ◽  
Grain Boundary Structure

ABSTRACTWe have modelled the grain boundaries in high-Tc superconducting oxides and determined the critical current density. The tunneling of superconducting pairs across the coalesced regions is used to determine the boundary effects. The length of the coalesced regions, with continuity of the Cu-O planes maintained by relaxation of the atom positions, is determined by minimization of the energy of the configuration. The depression of the order parameter is evaluated using the continuity conditions at the boundary in the proximity effect formulation. The excess charge distribution at the core of the boundary, determined from the solution to the Poisson's equation, is used to determine the scattering of the superconducting pairs. The width of the boundary, evaluated from modelling, determines the transmission coefficient for tunnelingof superconducting pairs. The critical current density is expressed in terms of these four important factors associated with the grain boundary. All the experimental results are explained by the present modelling of the grain boundary effects.

Grain boundary microstructure and transport critical current density in YBa2Cu3Ox

1992 ◽  
Author(s):  
Donglu Shi ◽  
Yufei Gao ◽  
A. C. Biondo ◽  
J. G. Chen ◽  
K. L. Merkle ◽  
...  
Keyword(s):  
Grain Boundary ◽  
Critical Current Density ◽  
Critical Current ◽  
Current Density ◽  
Transport Critical Current Density ◽  
Boundary Microstructure

The interfacial structure of orthogonally oriented twins in YBa2Cu3O7

1993 ◽  
Vol 51 ◽  
pp. 938-939
Author(s):  
Yimei Zhu ◽  
M. Suenaga ◽  
J. Tafto
Keyword(s):  
Grain Boundary ◽  
Critical Current Density ◽  
Critical Current ◽  
Twin Boundary ◽  
Current Density ◽  
Interfacial Structure ◽  
Hrem Image ◽  
Twin Boundaries ◽  
Wedge Shape

Interfaces such as the twin boundary and grain boundary in YBa2Cu3O7-δ are thought to be important in reconciling the large discrepancy between the low critical-current density observed in bulk polycrystalline. Recently, we studied another type of frequently encountered interface, i.e., the interface between the orthogonally orientated (110) and (-110) twins. In the vicinity of the interface, the crystal has a characteristic geometry because of additional constrains due to the impediment and the local orientational difference. The impinging twins usually have a wedge shape (Fig. la), and when the wedge slope is large, the tip of the twin splits (Fig. lb). A HREM image of a tapered twin is shown in Fig.2. Four twin variants give rise to five boundaries. Boundaries between IV-III, III-IV, IV-II, and II-IV are twin boundaries, while II-III, which has no apparent structure, is the interface of the orthogonal twins. If there is no constrain, the orientation of II and III should be equivalent (Fig.3a and 3b); however, we observed that the lattice in II does not align with that in III.

TEM Characterization of Grain Boundary Structure in YBCO Coated Conductors

2000 ◽  
Vol 6 (S2) ◽  
pp. 394-395
Author(s):  
H. Kung ◽  
J.P. Hirth ◽  
S.R. Foltyn ◽  
P.N. Arendt ◽  
Q.X. Jia ◽  
...  
Keyword(s):  
Grain Boundary ◽  
Critical Current Density ◽  
Grain Boundaries ◽  
Critical Current ◽  
Current Density ◽  
Lattice Mismatch ◽  
Coupling Effect ◽  
High Temperature Superconductors ◽  
Coated Conductors ◽  
Boundary Structure

Studies of defects, such as grain boundaries, in high temperature superconductors (HTS) are important due to the interaction of the defects with flux-bearing vortices. The benefit of in-plane grain alignment has been documented in YBCO thin film bicrystals, in which the high critical current density (Jc) observed across small angle grain boundaries deteriorates exponentially with grain boundary angles beyond ∼ 7°. In addition to the weak coupling effect, a grain boundary may also influence the transport properties via the grain boundary dislocations (GBDs) serving as pinning centers to increase the critical current density. There have been a number of studies on grain boundary structures in YBCO. Despite many differences in structure among the different types of boundaries, it has been established that the low angle [001] tilt boundary in YBCO consists of aperiodic array of edge type GBDs with [100] type Burgers vector that accommodate the lattice mismatch, and the regions between the GBDs are channels of relatively undisturbed lattices [1].

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