An Approximate Analysis of Stresses in Multilayered Elastic Thin Films

1988 ◽  
Vol 55 (1) ◽  
pp. 143-148 ◽  
Author(s):  
E. Suhir

The analysis contains an engineering method for the approximate evaluation of thermally induced stresses in single and multilayered heteroepitaxial structures fabricated on thick substrates, with consideration of the finite size of the structure. The examined stresses include normal stresses, acting in the film layers themselves and responsible for their ultimate and fatigue strength, as well as interfacial stresses, responsible for film blistering and peeling. The developed formulas are simple, easy-to-use, and clearly indicate how material and structural characteristics affect the magnitude and the distribution of stresses and deflections. Some recommendations for smaller stresses in film structures are presented. The obtained results can be utilized as a guidance for physical design of multilayered heteroepitaxial structures in microelectronics.

1987 ◽  
Vol 91 ◽  
Author(s):  
E. Suhir

ABSTRACTThe analysis contains an engineering method for the prediction of thermally induced stresses in single- and multilayered heteroepitaxial structures on a thick substrate. The examined stresses include 1) normal stresses acting in the film layers themselves and responsible for their ultimate and fatigue strength, and 2) interfacial stresses responsible for film blistering and peeling. The developed formulas are simple, visible, easy-to-use, and clearly indicate how material and structural characteristics affect the magnitude and the distribution of stresses and deflections. Some recommendations for smaller stresses in film structures are presented. The obtained results can be utilized as a guidance for an optimal physical design of multilayered heteroepitaxial structures used in Microelectronics.


2009 ◽  
Vol 105 (11) ◽  
pp. 113520 ◽  
Author(s):  
Dong Guo ◽  
Susumu Ikeda ◽  
Koichiro Saiki

1994 ◽  
Vol 338 ◽  
Author(s):  
U. Burges ◽  
H. Helneder ◽  
H. KÖrner ◽  
H. Schroeder ◽  
W. Schilling

ABSTRACTA bending beam technique was used to measure the mechanical stresses in AlSi(l%)Cu(0.5%) blanket films as well as in patterned lines (aspect ratio: 0.8) - unpassivated and passivated with SiNx - during thermal cycling from –170°C or room temperature to 450°C.Main results are:a) No significant differences in unpassivated and passivated blanket films with thickness ranging from 0.2 µm to 3.2 µm.b) In unpassivated patterned lines of 0.8 µm thickness the stresses across the lines are very small, while parallel to the lines they show nearly elastic behaviour, except at high temperatures.c) In passivated patterned lines the stresses are much higher than in blanket films, very similar parallel and across the line and nearly elastic. The stress relaxation is small compared with blanket films and depends strongly on the temperature.


Author(s):  
C. S. Giggins ◽  
J. K. Tien ◽  
B. H. Kear ◽  
F. S. Pettit

The performance of most oxidation resistant alloys and coatings is markedly improved if the oxide scale strongly adheres to the substrate surface. Consequently, in order to develop alloys and coatings with improved oxidation resistance, it has become necessary to determine the conditions that lead to spallation of oxides from the surfaces of alloys. In what follows, the morphological features of nonadherent Al2O3, and the substrate surfaces from which the Al2O3 has spalled, are presented and related to oxide spallation.The Al2O3, scales were developed by oxidizing Fe-25Cr-4Al (w/o) and Ni-rich Ni3 (Al,Ta) alloys in air at 1200°C. These scales spalled from their substrates upon cooling as a result of thermally induced stresses. The scales and the alloy substrate surfaces were then examined by scanning and replication electron microscopy.The Al2O3, scales from the Fe-Cr-Al contained filamentary protrusions at the oxide-gas interface, Fig. 1(a). In addition, nodules of oxide have been developed such that cavities were formed between the oxide and the substrate, Fig. 1(a).


2021 ◽  
Vol 114 ◽  
pp. 110966
Author(s):  
K. Erturk ◽  
M. Isik ◽  
M. Terlemezoglu ◽  
N.M. Gasanly

1991 ◽  
Vol 113 (3) ◽  
pp. 258-262 ◽  
Author(s):  
J. G. Stack ◽  
M. S. Acarlar

The reliability and life of an Optical Data Link transmitter are inversely related to the temperature of the LED. It is therefore critical to have efficient packaging from the point of view of thermal management. For the ODL® 200H devices, it is also necessary to ensure that all package seals remain hermetic throughout the stringent military temperature range requirements of −65 to +150°C. For these devices, finite element analysis was used to study both the thermal paths due to LED power dissipation and the thermally induced stresses in the hermetic joints due to ambient temperature changes


2015 ◽  
Vol 159 ◽  
pp. 118-121 ◽  
Author(s):  
Ernandes T. Tenório-Neto ◽  
Marcos R. Guilherme ◽  
Manuel E.G. Winkler ◽  
Lucio Cardozo-Filho ◽  
Stéphani C. Beneti ◽  
...  

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