Stress Relaxation during Isothermal Annealing at Elevated Temperatures in Electroplated Cu Films

2003 ◽  
Vol 795 ◽  
Author(s):  
Soo-Jung Hwang ◽  
Young-Chang Joo ◽  
Junichi Koike
Keyword(s):  
Thin Films ◽  
Stress Relaxation ◽  
Relaxation Process ◽  
Surface Diffusion ◽  
Elevated Temperatures ◽  
Isothermal Annealing ◽  
Slow Relaxation ◽  
Diffusion Creep ◽  
Relaxation Processes ◽  
Fast Relaxation

ABSTRACTDeformation mechanisms of electroplated Cu thin films on TaN/SiO2/Si were investigated by performing isothermal annealing above 200 °C. Stress relaxation behavior during isothermal annealing was analyzed by curve fitting using exponential decay equations. During heating, fast relaxation and subsequent slow relaxation processes were observed. In contrast, during cooling, only slow relaxation process was observed. Among possible mechanisms for stress relaxation, diffusion creep was found to be the most plausible mechanism based on the obtained values of the activation energy. It was suggested that the slow relaxation process observed both in the heating and in the cooling processes was attributed to a grain-boundary diffusion creep. On the other hand, the fast relaxation process observed during heating was attributed to a surface-diffusion controlled mechanism. The surface diffusion mechanism was considered to be characteristic to Cu thin films that did not form stable surface oxide.

Stress Relaxation Mechanisms in Rubbers Reinforced with Carbon Blacks

1972 ◽  
Vol 45 (1) ◽  
pp. 82-93 ◽  
Author(s):  
G. M. Bartenev ◽  
N. M. Lyalina
Keyword(s):  
Activation Energy ◽  
Stress Relaxation ◽  
Relaxation Process ◽  
Activation Energies ◽  
Relaxation Processes ◽  
Carbon Blacks ◽  
Multi Stage ◽  
Chemical Relaxation ◽  
Filled Rubbers ◽  
Weight Structures

Abstract 1. In vulcanized rubbers containing blacks a multi-stage mechanism for stress relaxation was observed. It was discovered that the stress relaxation process consists of five fundamental processes: the first three relaxation processes, related to the slow stages of physical relaxation within the bulk of the rubber, have no connection with the fillers (“soft” domains); the fourth process has to do with the relaxation in the black-rubber domain; the fifth process involves the chemical relaxation of vulcanizates. 2. The fundamental mechanisms of the first 3 relaxation processes in the soft domains have the same activation energy values and the same segmental mechanism as the rearranged domains found in supermolecular weight structures, which are also present in unfilled vulcanizates. 3. In the investigated stress range of up to 200% elongation, the activation energy for the first 3 relaxation processes in the soft domains of filled vulcanizates is not a function of the deformation strain, whereas the activation energy of the fourth relaxation process in the black-rubber domains of filled rubbers is a function of the deformation and of the filler content. For these reasons, rubber loaded with carbon blacks, in contrast to unfilled rubbers, possess the typical nonlinearity of viscoelastic materials. 4. The activation energies of the relaxation processes in the black-rubber domains decrease in a linear fashion with the value for the initial tensile stress in filled vulcanizates, and decrease in like manner for vulcanizates containing different proportions of fillers. The kinetic units, determined from the activation energies of these processes, appeared to be segments of chains with activation energies of up to 40% more than the activation energies of the physical relaxation processes in the soft domains. The other kinetic units of the processes proved to be black particles, the dimensions of which were calculated from the values for the coefficients in the formula for relaxation time.

Hydrogenography of PdHx thin films: Influence of H-induced stress relaxation processes

2009 ◽  
Vol 57 (4) ◽  
pp. 1209-1219 ◽  
Author(s):  
R. Gremaud ◽  
M. Gonzalez-Silveira ◽  
Y. Pivak ◽  
S. de Man ◽  
M. Slaman ◽  
...  
Keyword(s):  
Thin Films ◽  
Stress Relaxation ◽  
Relaxation Processes ◽  
Induced Stress

In-situ Measurement of Viscous Flow of Thermal Silicon Dioxide Thin Films at High Temperature

1996 ◽  
Vol 446 ◽  
Author(s):  
Chia-Liang Yu ◽  
Paul A. Flinn ◽  
John C. Bravman
Keyword(s):  
Thin Films ◽  
High Temperature ◽  
Stress Relaxation ◽  
Silicon Dioxide ◽  
Viscous Flow ◽  
Relaxation Process ◽  
Structural Relaxation ◽  
Wafer Curvature ◽  
Thermal Oxide

AbstractWith a newly constructed high temperature wafer curvature system, we measured significant viscous flow of thermal oxides at temperatures as low as 800°C. In-situ measurements were performed at temperatures between 800°C and 1100°C for wet and dry thermal oxide films of various thicknesses. We found that dry oxides have higher stresses and slower stress relaxation compared to wet oxides grown at higher temperatures. The viscosity of thermal oxide thin films was found to increase with time during relaxation and a structural relaxation process is suggested to explain this phenomenon.

In situ study of stress relaxation mechanisms of pure Al thin films during isothermal annealing

2006 ◽  
Vol 54 (11) ◽  
pp. 1841-1846 ◽  
Author(s):  
Soo-Jung Hwang ◽  
Yong-Duck Lee ◽  
Young-Bae Park ◽  
Je-Hun Lee ◽  
Chang-Oh Jeong ◽  
...  
Keyword(s):  
Thin Films ◽  
Stress Relaxation ◽  
Isothermal Annealing ◽  
In Situ Study

Slow relaxation of the magnetization observed in mononuclear Ln–radical compounds with D4d geometry configurations

2019 ◽  
Vol 48 (2) ◽  
pp. 558-565 ◽  
Author(s):  
Peng Yun Chen ◽  
Ming Ze Wu ◽  
Zhong Yi Liu ◽  
Li Tian ◽  
Yi Quan Zhang
Keyword(s):  
Relaxation Process ◽  
Slow Relaxation ◽  
Relaxation Processes

Three monometallic Ln-NIT complexes have been synthesized based on a pyrazole radical. The central LnIII ions are all in D4d polyhedron configurations. Tb's complex shows a single relaxation process. Dy's complex exhibits complicated relaxation processes.

scholarly journals Effect of Elevated Temperatures on the Mechanical Properties of a Direct Laser Deposited Ti-6Al-4V

Materials ◽  
2021 ◽  
Vol 14 (21) ◽  
pp. 6432
Author(s):  
Sergei Ivanov ◽  
Marina Gushchina ◽  
Antoni Artinov ◽  
Maxim Khomutov ◽  
Evgenii Zemlyakov
Keyword(s):  
Mechanical Properties ◽  
Stress Relaxation ◽  
Young’S Modulus ◽  
Elevated Temperatures ◽  
Coefficient Of Thermal Expansion ◽  
Young's Modulus ◽  
Tensile Tests ◽  
Process Conditions ◽  
Relaxation Processes ◽  
Direct Laser

In the present work, the mechanical properties of the DLD-processed Ti-6Al-4V alloy were obtained by tensile tests performed at different temperatures, ranging from 20 °C to 800 °C. Thereby, the process conditions were close to the conditions used to produce large-sized structures using the DLD method, resulting in specimens having the same initial martensitic microstructure. According to the obtained stress curves, the yield strength decreases gradually by 40% when the temperature is increased to 500 °C. Similar behavior is observed for the tensile strength. However, further heating above 500 °C leads to a significant increase in the softening rate. It was found that the DLD-processed Ti-6Al-4V alloy had a Young’s modulus with higher thermal stability than conventionally processed alloys. At 500 °C, the Young’s modulus of the DLD alloy was 46% higher than that of the wrought alloy. The influence of the thermal history on the stress relaxation for the cases where 500 °C and 700 °C were the maximum temperatures was studied. It was revealed that stress relaxation processes are decisive for the formation of residual stresses at temperatures above 700 °C, which is especially important for small-sized parts produced by the DLD method. The coefficient of thermal expansion was investigated up to 1050 °C.

scholarly journals Relaxation Phenomena in Chitosan-Au Nanoparticle Thin Films

Polymers ◽  
2021 ◽  
Vol 13 (19) ◽  
pp. 3214
Author(s):  
Elodie Strupiechonski ◽  
Marisa Moreno-Ríos ◽  
Erika O. Ávila-Dávila ◽  
Ramón Román-Doval ◽  
Evgeny Prokhorov ◽  
...  
Keyword(s):  
Thin Films ◽  
Glass Transition ◽  
Relaxation Process ◽  
Disordered Systems ◽  
Chemical Reduction ◽  
Sodium Succinate ◽  
Au Nanoparticle ◽  
Relaxation Processes ◽  
Potential Barriers ◽  
Percolation Effect

Chitosan–gold nanoparticle (CS/AuNP) thin films were synthesized through the chemical reduction of HAuCl4 in sodium citrate/chitosan solutions. The dielectric and dynamic mechanical behaviors of CS/AuNP films have been investigated as a function of moisture and HAuCl4 content. Two relaxation processes in the nanocomposites have been observed. The α-relaxation process is related to a glass transition in wet CS/AuNP films. However, in dry composites (with 0.2 wt% of moisture content), the glass transition vanished. A second relaxation process was observed from 70 °C to the onset of thermal degradation (160 °C) in wet films and from 33 °C to the onset of degradation in dry films. This relaxation is identified as the σ-relaxation and may be related to the local diffusion process of ions between high potential barriers in disordered systems. The α- and σ-relaxation processes are affected by the HAuCl4 content of the solutions from which films were obtained because of the interaction between CS, sodium succinate, and gold nanoparticles. With about 0.6 mM of HAuCl4, the conductivity of both wet and dry films sharply increased by six orders, corresponding to the percolation effect, which may be related to the appearance of a conductivity pathway between AuNPs, HAuCl4, and NaCl.

Effect of Dispersoids on Long-Term Stable Electrical Aluminium Connections

2016 ◽  
Vol 877 ◽  
pp. 409-415 ◽  
Author(s):  
Richard H. Kemsies ◽  
Benjamin Milkereit ◽  
Olaf Kessler ◽  
Torsten Fuhrmann ◽  
Stephan Schlegel ◽  
...  
Keyword(s):  
Stress Relaxation ◽  
Power Systems ◽  
Elevated Temperatures ◽  
Electrical Power ◽  
Bolted Joints ◽  
Relaxation Processes ◽  
Electrical Power Systems ◽  
Worst Case ◽  
Joint Force

In electrical power systems bolted joints with bus bars made of aluminium are common, whereby the tendency towards higher operating temperatures can be observed. At higher temperatures a reduction of the joint force can occur due to creep and/or stress relaxation processes, which leads to an increasing electrical resistance and, in the worst case, to failed joints. The aim of this project is to increase the creep resistance (and to minimise the stress relaxation) of aluminium conductors for electrical applications without a significant reduction in their electrical conductivity – even after long-term exposure to elevated temperatures. The effect of dispersoids in different aluminium alloys on the longterm behaviour of currentcarrying joints at high temperatures (i.e. 140 °C) was investigated. Longterm tests on bolted joints with force measuring devices were performed to monitor the joint forces and to measure the joint resistances, both with and without current supply.

Stress Relaxation and the Formation of Silicides in the Process of the Crystallization of NI-NB Films on SI

1991 ◽  
Vol 49 ◽  
pp. 898-899
Author(s):  
N. Rozhanski ◽  
V. Lifshitz
Keyword(s):  
Thin Films ◽  
Stress Relaxation ◽  
Integrated Circuits ◽  
Direct Evidence ◽  
Alloy Film ◽  
Diffusion Barriers ◽  
Effective Barrier

Thin films of amorphous Ni-Nb alloys are of interest since they can be used as diffusion barriers for integrated circuits on Si. A native SiO2 layer is an effective barrier for Ni diffusion but it deformation during the crystallization of the alloy film lead to the appearence of diffusion fluxes through it and the following formation of silicides. This study concerns the direct evidence of the action of stresses in the process of the crystallization of Ni-Nb films on Si and the structure of forming NiSi2 islands.

WIELAND-K88

Alloy Digest ◽  
2005 ◽  
Vol 54 (12) ◽  
Keyword(s):  
Thermal Conductivity ◽  
Corrosion Resistance ◽  
High Temperature ◽  
Stress Relaxation ◽  
Copper Alloy ◽  
Elevated Temperatures ◽  
Heat Treating ◽  
Relaxation Resistance ◽  
Temperature Performance ◽  
Very High

Abstract Wieland K-88 is a copper alloy with very high electrical and thermal conductivity, good strength, and excellent stress relaxation resistance at elevated temperatures. This datasheet provides information on composition, physical properties, hardness, elasticity, and tensile properties. It also includes information on high temperature performance and corrosion resistance as well as forming, heat treating, machining, joining, and surface treatment. Filing Code: CU-738. Producer or source: Wieland Metals Inc.

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