Morphology, kinetics, and thermodynamics of solid-state aging of eutectic SnPb and Pb-free solders (Sn–3.5Ag, Sn–3.8Ag–0.7Cu and Sn–0.7Cu) on Cu

2002 ◽  
Vol 17 (2) ◽  
pp. 291-301 ◽  
Author(s):  
T. Y. Lee ◽  
W. J. Choi ◽  
K. N. Tu ◽  
J. W. Jang ◽  
S. M. Kuo ◽  
...  
Keyword(s):  
Activation Energy ◽  
Solid State ◽  
Ternary Phase ◽  
The Other ◽  
Molten State ◽  
Under Bump Metallization ◽  
Kinetics And Thermodynamics ◽  
Intermetallic Growth ◽  
Ternary Phase Diagrams ◽  
Eutectic Snpb

Intermetallic compound (IMC) growth during solid-state aging at 125, 150, and 170 °C up to 1500 h for four solder alloys (eutectic SnPb, Sn–3.5Ag, Sn–3.8Ag–0.7Cu, and Sn–0.7Cu) on Cu under bump metallization was investigated. The samples were reflowed before aging. During the reflow, the solders were in the molten state and the formation of the IMC Cu6Sn5 in the cases of eutectic SnPb and Sn–3.5Ag had a round scallop-type morphology, but in Sn–0.7Cu and Sn–3.8Ag–0.7Cu the scallops of Cu6Sn5 were faceted. In solid-state aging, all these scallops changed to a layered-type morphology. In addition to the layered Cu6Sn5, the IMC Cu3Sn also grew as a layer and was as thick as the Cu6Sn5. The activation energy of intermetallic growth in solid-state aging is 0.94 eV for eutectic SnPb and about 1.05 eV for the Pb-free solders. The rate of intermetallic growth in solid-state aging is about 4 orders of magnitude slower than that during reflow. Ternary phase diagrams of Sn–Pb–Cu and Sn–Ag–Cu are used to discuss the reactions. These diagrams predict the first phase of IMC formation in the wetting reaction and the other phases formed in solid-state aging. Yet, the morphological change and the large difference in growth rates between the wetting reaction and solid-state aging cannot be predicted.

Interfacial Microstructure Evolution Between Eutectic SnAgCu Solder and Al/Ni(V)/Cu Thin Films

2002 ◽  
Vol 17 (7) ◽  
pp. 1612-1621 ◽  
Author(s):  
M. Li ◽  
F. Zhang ◽  
W. T. Chen ◽  
K. Zeng ◽  
K. N. Tu ◽  
...  
Keyword(s):  
Thin Films ◽  
Phase Diagram ◽  
Solid State ◽  
Brittle Failure ◽  
Ternary Phase ◽  
Interfacial Microstructure ◽  
Snagcu Solder ◽  
Ball Shear ◽  
Aging Study ◽  
Eutectic Snpb

The evolution of interfacial microstructure of eutectic SnAgCu and SnPb solders on Al/Ni(V)/Cu thin films was investigated after various heat treatments. In the eutectic SnPb system, the Ni(V) layer was well protected after 20 reflow cycles at 220 °C. In the SnAgCu solder system, after 5 reflow cycles at 260 °C, the (Cu,Ni)6Sn5 ternary phase formed and Sn was detected in the Ni(V) layer. After 20 reflow cycles, the Ni(V) layer disappeared and spalling of the (Cu,Ni)6Sn5 was observed, which explains the transition to brittle failure mode after ball shear testing. The different interfacial reactions that occurred in the molten SnAgCu and SnPb systems were explained in terms of different solubilities of Cu in the two systems. The dissolution and formation of the (Cu,Ni)6Sn5phase were discussed on the basis of a Sn–Ni–Cu phase diagram. In the solid-state aging study of the SnAgCu samples annealed at 150 °C for up to 1000 h, the Ni(V) layer was intact and the intermetallic compound formed was Cu6Sn5 and not (Cu,Ni)6Sn5, which is the same as was observed for the eutectic SnPb system.

Epitaxial Growth of Metallic Layers by Solid Phase Interdiffusion : Study of the Ni/GaAs and Ni/AlAs Systems

1989 ◽  
Vol 160 ◽  
Author(s):  
Roland Guerin ◽  
S. Deputier ◽  
J. Caulet ◽  
M. Minier ◽  
A. Poudoulec ◽  
...  
Keyword(s):  
Solid State ◽  
Metal Film ◽  
Ternary Phase ◽  
Annealing Temperature ◽  
Solid Phase ◽  
Metallic Films ◽  
Ternary Phase Diagrams ◽  
Starting Point ◽  
Semiconductor Contact

AbstractAn ideal metal/III-V semiconductor contact should be made by stable and epitaxial metallic films. In principle, such a contact may be obtained by the solid state ΐnterdiffusion of a metal film with a III-V SC substrate. We studied the solid state interdiffusions in the Ni/GaAs and Ni/AlAs systems. Our starting point was the experimental determination of the Ni-Ga-As and Ni-Al-As ternary phase diagrams. The main steps of the interaction appear to be different in the two systems. During the Ni/GaAs one, three successive steps as a function of the annealing temperature are observed : first a mixture of a Ga-rich ternary phase (C phase) + NiAs, then C phase + NiAs + NiGa and at last the two binaries NiAs + NiGa where the reaction stops. In the case of the Ni/AlAs reactions, the three steps successively correspond to a mixture of NiAl + an As-rich ternary phase then NiAl + another As-rich ternary phase + NiAs and finally NiAl + NiAs. NiAs and NiAl are the key compounds in Ni/GaAs and Ni/AlAs reactions respectively and all the reaction compounds are either textured (pseudocubic NiAs and ternaries) or epitaxial (cubic binaries NiGa and NiAl).

Measurement of electromigration activation energy in eutectic SnPb and SnAg flip-chip solder joints with Cu and Ni under-bump metallization

2010 ◽  
Vol 25 (9) ◽  
pp. 1847-1853 ◽  
Author(s):  
Hsiao-Yun Chen ◽  
Chih Chen
Keyword(s):  
Activation Energy ◽  
Flip Chip ◽  
Void Formation ◽  
Under Bump Metallization ◽  
Solder Bumps ◽  
Snpb Solder ◽  
Snag Solder ◽  
Temperature Coefficient Of Resistivity ◽  
Eutectic Snpb ◽  
Real Temperature

Electromigration activation energy is measured by a built-in sensor that detects the real temperature during current stressing. Activation energy can be accurately determined by calibrating the temperature using the temperature coefficient of resistivity of an Al trace. The activation energies for eutectic SnAg and SnPb solder bumps are measured on Cu under-bump metallization (UBM) as 1.06 and 0.87 eV, respectively. The activation energy mainly depends on the formation of Cu–Sn intermetallic compounds. On the other hand, the activation energy for eutectic SnAg solder bumps with Cu–Ni UBM is measured as 0.84 eV, which is mainly related to void formation in the solder.

A comparative study of sintered and melt-grown recrystallized YBa2Cu3Ox

1989 ◽  
Vol 4 (1) ◽  
pp. 28-32 ◽  
Author(s):  
Hamid Hojaji ◽  
Karen A. Michael ◽  
Aaron Barkatt ◽  
Arthur N. Thorpe ◽  
Matthew F. Ware ◽  
...  
Keyword(s):  
Solid State ◽  
Comparative Study ◽  
The Other ◽  
Current Paper ◽  
Molten State ◽  
Magnetization Measurements ◽  
Yttrium Barium Cuprate ◽  
Solid State Sintering ◽  
Yttrium Barium

This paper compares the properties of yttrium barium cuprate bulk specimens prepared by means of solid-state sintering on one hand and of growth from a largely molten state on the other. The current paper focuses on magnetization measurements at 77 K which show specimens made by the latter method to have high remanence magnetization values.

Phase equilibria of the Cu–Dy–Ti ternary system at 973 K

2015 ◽  
Vol 30 (3) ◽  
pp. 218-223
Author(s):  
Yanfang Pan ◽  
Hao Liu ◽  
Wenchao Yang ◽  
Bo Zhang ◽  
Hongqun Tang ◽  
...  
Keyword(s):  
Solid State ◽  
Ternary System ◽  
Phase Equilibria ◽  
Homogeneity Range ◽  
Solid Solubility ◽  
Ternary Phase ◽  
Single Phase ◽  
Phase Relations ◽  
The Other ◽  
Binary Compounds

The solid-state phase equilibria of the copper (Cu)–dysprosium (Dy)–titanium (Ti) ternary system at 973 K has been experimentally investigated. The existence of nine binary compounds, Cu4Ti, Cu3Ti2, Cu4Ti3, CuTi, CuTi2, CuTi3, CuDy, Cu2Dy, and Cu5Dy was confirmed. The controversial phase of CuTi3 was found in this work. The temperature range of Cu7Dy was determined to be from 1112 to 1183 K. The phase relations at 973 K are governed by ten ternary phase regions, 21 binary phase regions, and 12 single-phase regions. The solid solubility of Cu in Dy is undetectable. None of the other phase in this system reveals a remarkable homogeneity range at 973 K.

The use of acoustic spectroscopy in the characterisation of ternary phase diagrams

2013 ◽  
Vol 441 (1-2) ◽  
pp. 603-610 ◽  
Author(s):  
Giulia Bonacucina ◽  
Marco Cespi ◽  
Giovanna Mencarelli ◽  
Luca Casettari ◽  
Giovanni F. Palmieri
Keyword(s):  
Phase Diagrams ◽  
Ternary Phase ◽  
Ternary Phase Diagrams ◽  
Acoustic Spectroscopy

scholarly journals Na3Co2(As0.52P0.48)O4(As0.95P0.05)2O7

2013 ◽  
Vol 69 (12) ◽  
pp. i85-i86 ◽  
Author(s):  
Youssef Ben Smida ◽  
Abderrahmen Guesmi ◽  
Mohamed Faouzi Zid ◽  
Ahmed Driss
Keyword(s):  
Solid State ◽  
Solid State Reaction ◽  
Title Compound ◽  
General Position ◽  
Structural Model ◽  
Three Dimensional ◽  
The Other ◽  
Coordination Polyhedra ◽  
Bond Valence Sum ◽  
Full Occupancy

The title compound, trisodium dicobalt(II) (arsenate/phosphate) (diarsenate/diphosphate), was prepared by a solid-state reaction. It is isostructural with Na3Co2AsO4As2O7. The framework shows the presence of CoX22O12(X2 is statistically disordered with As0.95P0.05) units formed by sharing corners between Co1O6octahedra andX22O7groups. These units form layers perpendicular to [010]. Co2O6octahedra andX1O4(X1 = As0.54P0.46) tetrahedra form Co2X1O8chains parallel to [001]. Cohesion between layers and chains is ensured by theX22O7groups, giving rise to a three-dimensional framework with broad tunnels, running along thea- andc-axis directions, in which the Na+ions reside. The two Co2+cations, theX1 site and three of the seven O atoms lie on special positions, with site symmetries 2 andmfor the Co,mfor theX1, and 2 andm(× 2) for the O sites. One of two Na atoms is disordered over three special positions [occupancy ratios 0.877 (10):0.110 (13):0.066 (9)] and the other is in a general position with full occupancy. A comparison between structures such as K2CdP2O7, α-NaTiP2O7and K2MoO2P2O7is made. The proposed structural model is supported by charge-distribution (CHARDI) analysis and bond-valence-sum (BVS) calculations. The distortion of the coordination polyhedra is analyzed by means of the effective coordination number.

scholarly journals Removal of Chromium from Aqueous Solution Using Modified Pomegranate Peel:Mechanistic and Thermodynamic Studies

2009 ◽  
Vol 6 (s1) ◽  
pp. S153-S158 ◽  
Author(s):  
Tariq S. Najim ◽  
Suhad A. Yassin
Keyword(s):  
Activation Energy ◽  
Solid Solution ◽  
Aqueous Solution ◽  
Adsorption Process ◽  
Batch Process ◽  
The Other ◽  
Water Molecules ◽  
Pomegranate Peel ◽  
Solution Interface ◽  
Adsorbent Surface

Modified pomegranate peel (MPGP) and formaldehyde modified pomegranate peel (FMPGP) were prepared and used as adsorbent for removal of Cr(VI) ions from aqueous solution using batch process. The temperature variation study of adsorption on both adsorbents revealed that the adsorption process is endothermic, from the positive values of ∆H˚. These values lie in the range of physisorption. The negative values of ∆G˚ show the adsorption is favorable and spontaneous. On the other hand, these negative values increases with increase in temperature on both adsorbents, which indicate that the adsorption is preferable at higher temperatures. ∆S˚ values showed that the process is accompanied by increase in disorder and randomness at the solid solution interface due to the reorientation of water molecules and Cr(VI) ions around the adsorbent surface. The endothermic nature of the adsorption was also confirmed from the positive values of activation energy, Ea, the low values of Ea confirm the physisorption mechanism of adsorption. The sticking probability, S*, of Cr(VI) ion on surface of both adsorbents showed that the adsorption is preferable due to low values of S*(0< S*< 1 ), but S*values are lower for FMPGP indicating that the adsorption on FMPGP is more preferable .

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