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 ◽  
...  

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.

1985 ◽  
Vol 16 ◽  
pp. 179-184 ◽  
Author(s):  
P RAMAEKERS ◽  
F VANLOO ◽  
G BASTIN ◽  
R METSELAAR

1988 ◽  
Vol 100 ◽  
Author(s):  
I. L. Singer ◽  
R. G. Vardiman ◽  
C. R. Gossett

ABSTRACTTi+ ions were implanted to high fluences (up to 5 × 1017 /cm2 ) into Si3N4 substrates heated to around 900°C. Composition vs depth profiles were obtained by RBS (in conjunction with RUMP analysis) and microstructures were examined by TEM. At a fluence of 4 × 1017 /cm2, the Si concentration was considerably reduced at the Ti peak depth but enriched near the surface. By 5 × 1017 /cm2, Si was nearly depleted from the implanted layer, leaving a Ti-rich nitride layer merging continuously into Si3N4. TEN detected TiN precipitates up to several pm in diameter, and coherent with Si3N4 crystallites. A Si-Ti-N ternary phase diagram is used to interpret the observed solid state reactions.


1989 ◽  
Vol 169 ◽  
Author(s):  
T. D. Rolin ◽  
F. S. Cheng ◽  
J. R. Ashburn ◽  
H. Y. Cheng ◽  
E. E. Anderson

AbstractWe have investigated the Y‐Sr‐Cu‐O system which has been reported to form a K2NiF4‐type superconducting phase (TC∼40K) and a “123”‐type phase (Tc‐80K). Difficulties in preparing single phase materials by standard solid state reaction of carbonates and oxides have compelled us to explore other methods. A two‐stage solid state processing technique in addition to a coprecipitation method will be discussed along with the relative advantages and disadvantages of each. Using data obtained from XRD and EDS, we have mapped some of the YO1.5‐SrO‐CuO ternary phase diagram in anticipation of continued efforts at single crystal growth.


2002 ◽  
Vol 17 (2) ◽  
pp. 291-301 ◽  
Author(s):  
T. Y. Lee ◽  
W. J. Choi ◽  
K. N. Tu ◽  
J. W. Jang ◽  
S. M. Kuo ◽  
...  

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.


Author(s):  
F. Ma ◽  
S. Vivekanand ◽  
K. Barmak ◽  
C. Michaelsen

Solid state reactions in sputter-deposited Nb/Al multilayer thin films have been studied by transmission and analytical electron microscopy (TEM/AEM), differential scanning calorimetry (DSC) and X-ray diffraction (XRD). The Nb/Al multilayer thin films for TEM studies were sputter-deposited on (1102)sapphire substrates. The periodicity of the films is in the range 10-500 nm. The overall composition of the films are 1/3, 2/1, and 3/1 Nb/Al, corresponding to the stoichiometric composition of the three intermetallic phases in this system.Figure 1 is a TEM micrograph of an as-deposited film with periodicity A = dA1 + dNb = 72 nm, where d's are layer thicknesses. The polycrystalline nature of the Al and Nb layers with their columnar grain structure is evident in the figure. Both Nb and Al layers exhibit crystallographic texture, with the electron diffraction pattern for this film showing stronger diffraction spots in the direction normal to the multilayer. The X-ray diffraction patterns of all films are dominated by the Al(l 11) and Nb(l 10) peaks and show a merging of these two peaks with decreasing periodicity.


Author(s):  
Rachel Orenstein ◽  
James P. Male ◽  
Michael Toriyama ◽  
Shashwat Anand ◽  
G. Jeffrey Snyder

A new understanding of the MgSi–MgSn miscibility gap is reached through phase boundary mapping the Mg–Si–Sn ternary phase diagram.


Nanomaterials ◽  
2021 ◽  
Vol 11 (6) ◽  
pp. 1494
Author(s):  
Mustapha El Hariri El Nokab ◽  
Khaled O. Sebakhy

Solid-state NMR has proven to be a versatile technique for studying the chemical structure, 3D structure and dynamics of all sorts of chemical compounds. In nanotechnology and particularly in thin films, the study of chemical modification, molecular packing, end chain motion, distance determination and solvent-matrix interactions is essential for controlling the final product properties and applications. Despite its atomic-level research capabilities and recent technical advancements, solid-state NMR is still lacking behind other spectroscopic techniques in the field of thin films due to the underestimation of NMR capabilities, availability, great variety of nuclei and pulse sequences, lack of sensitivity for quadrupole nuclei and time-consuming experiments. This article will comprehensively and critically review the work done by solid-state NMR on different types of thin films and the most advanced NMR strategies, which are beyond conventional, and the hardware design used to overcome the technical issues in thin-film research.


JOM ◽  
2021 ◽  
Author(s):  
Evgeny T. Moiseenko ◽  
Sergey M. Zharkov ◽  
Roman R. Altunin ◽  
Oleg V. Belousov ◽  
Leonid A. Solovyov ◽  
...  

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