Electromigration in metals

1977 ◽  
Vol 55 (2) ◽  
pp. 103-115 ◽  
Author(s):  
S. T. Pai ◽  
J. P. Marton
Keyword(s):  
Thin Film ◽  
Experimental Data ◽  
Elevated Temperature ◽  
Temperature Gradient ◽  
Electrostatic Force ◽  
Electrical Current ◽  
Net Migration ◽  
Sample Position ◽  
Hole Current ◽  
Reversal Temperature

In bulk and thin film metal samples, a net migration of material may take place when electrical current is passed through the sample at an elevated temperature. The migration is due to the passage of electron (or hole) current, the electrostatic force on the metal ions, and the temperature gradient in the sample. The extent and the direction of net migration has not been predicted satisfactorily by existing theories, leaving many unexplained anomalous experimental results. The present work is the development of a generalized theory that contains the main features of previous theories. It can explain all major experimental observations. Its main features include predictions on the temperature and time dependence of migration, its direction, its reversal temperature, and the approximate sample position that is affected most. The theory has been used to interpret available experimental data on a number of electron- and hole-type metals.

scholarly journals The Development of Precision Thin Film Resistors for Submerged Repeater Applications

1978 ◽  
Vol 5 (1) ◽  
pp. 9-14 ◽  
Author(s):  
D. O. Spiller
Keyword(s):  
Thin Film ◽  
Experimental Data ◽  
Mathematical Model ◽  
Elevated Temperature ◽  
Electrochemical Corrosion ◽  
Life Test ◽  
Film Resistor ◽  
Thin Film Resistor ◽  
Diffusion Effects ◽  
Thin Film Resistors

The paper describes development of a low inductance thin film resistor series with a stability of ±0.15% change in resistance, over a 25 year life, in a submerged repeater environment. (40% RH maximum and 0 to 30℃ ambient temperature).It was first necessary to establish an appropriate mathematical model relating resistor stability with time and temperature. This was devised from experimental data based on measured resistor drift at various temperatures, and enabled acceleration of resistor drift to be carried out to ensure that each resistor possessed the required stability.Deposition of a secondary nichrome layer protects the gold/nichrome interface and promotes SiO2adhesion. This results in an improvement in the basic elevated temperature resistor stability by minimising diffusion effects of nichrome into the conductor, and protection against electrochemical corrosion as demonstrated by 10,000 hours life test at 83% RH @ 28℃ on 5 mW load and by elevated temperature tests under electrical loading.

Indentation Technique to Investigate Elastic Moduli of Thin Films on Substrates

1988 ◽  
Vol 130 ◽  
Author(s):  
D. S. Stone ◽  
T. W. Wu ◽  
P.-S. Alexopoulos ◽  
W. R. Lafontaine
Keyword(s):  
Thin Film ◽  
Experimental Data ◽  
Thin Films ◽  
Closed Form ◽  
Elastic Moduli ◽  
Depth Sensing ◽  
Indentation Technique ◽  
Average Displacement ◽  
Elasticity Solutions ◽  
Poor Adhesion

AbstractClosed-form elasticity solutions are introduced, that predict the average displacement beneath square and triangular, uniformly loaded areas at the surface of a bilayer. The solutions aid in the application of depth-sensing indentation techniques for measuring thin film elastic moduli. The elasticity solutions agree closely with experimental data of Al, Si, 1 μm Al on Si, and 2 μm Cr on Si. The case of poor adhesion between the film and substrate is briefly examined.

Detection Limit of Large Area Id Thin Film Position Sensitive Detectors Based in a-Si:H P.I.N. Diodes

1995 ◽  
Vol 377 ◽  
Author(s):  
R. Martins ◽  
G. Lavareda ◽  
F. Soares ◽  
E. Fortunato
Keyword(s):  
Thin Film ◽  
Experimental Data ◽  
Steady State ◽  
Detection Limit ◽  
Large Area ◽  
Position Sensitive ◽  
Position Sensitive Detectors

ABSTRACTThe aim of this work is to provide the basis for the interpretation of the steady state lateral photoeffect observed in p-i-n a-Si:H ID Thin Film Position Sensitive Detectors (ID TFPSD). The experimental data recorded in ID TFPSD devices with different performances are compared with the predicted curves and the obtained correlation's discussed.

L10 FePt–MgO perpendicular thin film deposited by alternating sputtering at elevated temperature

2006 ◽  
Vol 99 (8) ◽  
pp. 08F907 ◽  
Author(s):  
Yingguo Peng ◽  
Jian-Gang Zhu ◽  
David E. Laughlin
Keyword(s):  
Thin Film ◽  
Elevated Temperature

Effect of High Temperature on Concrete: A Literature Review

2006 ◽  
Vol 302-303 ◽  
pp. 138-149 ◽  
Author(s):  
Gai Fei Peng ◽  
Sammy Yin Nin Chan ◽  
Qi Ming Song ◽  
Quan Xin Yi
Keyword(s):  
Experimental Data ◽  
Mechanical Properties ◽  
High Temperature ◽  
Elevated Temperature ◽  
Literature Review ◽  
High Strength Concrete ◽  
High Strength ◽  
Research Needs ◽  
Standard Fire ◽  
Fire Condition

This paper presents a review on the effect of fire on concrete, citing 43 references. It was found that most of them are on the behavior of concrete under high temperature conditions more or less different from the standard fire condition. The problem of spalling, which high-strength concrete encounters when exposed to fire, is especially urgent to solve. Since the literature on the behavior of concrete under fire conditions is very limited, the literature even under elevated temperature has to be used as a part of the base of further research. The further research needs urgently to be carried out under the standard fire condition. Residual mechanical properties reported in most previous literature might be overestimated, where natural cooling was usually employed. Proper evaluation of fire resistance of concrete needs more experimental data obtained under various cooling regimes such as water spraying or water quenching.

A New Postulation of Viscosity and Its Application in Computation of Film Thickness in TFL1

2002 ◽  
Vol 124 (4) ◽  
pp. 811-814 ◽  
Author(s):  
Chaohui Zhang ◽  
Jianbin Luo ◽  
Shizhu Wen
Keyword(s):  
Thin Film ◽  
Experimental Data ◽  
Film Thickness ◽  
Solid Surface ◽  
Contact Area ◽  
Elastohydrodynamic Lubrication ◽  
Thin Film Lubrication ◽  
Lubrication Film ◽  
Viscosity Modification ◽  
Film Lubrication

In this paper, a viscosity modification model is developed which can be applied to describe the thin film lubrication problems. The viscosity distribution along the direction normal to solid surface is approached by a function proposed in this paper. Based on the formula, lubricating problem of thin film lubrication (TFL) in isothermal and incompressible condition is solved and the outcome is compared to the experimental data. In thin film lubrication, according to the computation outcomes, the lubrication film thickness is much greater than that in elastohydrodynamic lubrication (EHL). When the velocity is adequately low (i.e., film thickness is thin enough), the pressure distribution in the contact area is close to Hertzian distribution in which the second ridge of pressure is not obvious enough. The film shape demonstrates the earlobe-like form in thin film lubrication, which is similar to EHL while the film is comparatively thicker. The transformation relationships between film thickness and loads, velocities or atmosphere viscosity in thin film lubrication differ from those in EHL so that the transition from thin film lubrication to EHL can be clearly seen.

scholarly journals Effect of elevated temperature on green gram [Vigna radiata (I).Wilczek] performance under temperature gradient tunnel (TGT) environment in Punjab

2021 ◽  
Vol 23 (1) ◽  
pp. 3-13
Author(s):  
HARPREET SINGH ◽  
PRABHJYOT KAUR ◽  
S.K. BAL ◽  
B.U. CHOUDHURY
Keyword(s):  
Elevated Temperature ◽  
Temperature Gradient ◽  
Grain Yield ◽  
Harvest Index ◽  
Elevated Temperatures ◽  
Ambient Condition ◽  
Green Gram ◽  
Seasonal Temperature ◽  
Early Maturity ◽  
Semi Arid

Physiology of green gram is highly sensitive to fluctuations in the thermal environment. Abnormally high temperatures during pod setting to pod development stage induces reduction in pod setting, nonhealthy development and early maturity of grain which results in yield decline. We evaluated the effect of elevated temperatures in a Temperature Gradient Tunnel (TGT) on phenology, physiology and crop performance of green gram cultivars at semi-arid climate of Indian Punjab (Ludhiana). Five green gram cultivars were grown in TGT chambers in a factorial randomized block design with varying level of elevated temperatures (+3.3° C to 5.2° C) for two consecutive kharif seasons (2015-2016). The results reveal that the phenological stages of green gram, were advanced under elevated temperature within the TGT compared to open / ambient condition by 12-13 days. Maximum influence was observed in pod formationand pod maturity stages. With rise in temperatures by 3.3 to 5.2°C in TGT over ambient condition, the plant height increased but the number of branches per plant and the total above ground biomass as well as grain yield decreased consistently. It was found that with 1 oC increase in average seasonal temperature, the grain yield decreased by 75 kg ha-1. On the other hand, the harvest index was in general lower inside TGT chamber implying adverse influence of elevated temperature on biomass production although the partitioning of biomass was more efficient inside the TGT as evident from increase in harvest index. There was strong negative correlation of elevated temperature (inside TGT) with different yield attributes like 1000 seed weight, number of seeds per pod and number of pods per plant. Among the five green gram cultivars, ML-2037 was the most tolerant while cv. SML-1811 was the most susceptible to elevated temperature condition. In general, the grain yield decreased linearly with gradual increase in temperature.Average seasonal temperature of 29-30 oC may be considered as the favourable thermal conditions for the green gram crop in semi-arid conditions of Punjab. However, the future thrust will be to create more temperature gradients in the lower side so that the critical temperature threshold limits for optimum yield of green gram can be ascertained more accurately.

Statistical Model of a Thin Film Formation

2021 ◽  
Vol 887 ◽  
pp. 597-602
Author(s):  
E.L. Kuleshov ◽  
Vladimir S. Plotnikov ◽  
Evgenii V. Pustovalov ◽  
T.S. Ostachenova
Keyword(s):  
Thin Film ◽  
Experimental Data ◽  
Probability Distribution ◽  
Amorphous Alloy ◽  
Statistical Model ◽  
Pareto Distribution ◽  
Film Formation ◽  
Informational Entropy ◽  
Thin Film Formation ◽  
Conditional Unit

This paper presents a model of a thin film formation process of an amorphous alloy as a sequential procedure when a conditional unit of substance is randomly thrown onto a substrate at each next step. The islands of a precipitant are generated on the substrate with an increase of number of steps (density defects of substance). We determine the probability distribution of an island area, which shows the maximum informational entropy. An algorithm for computing estimates of parameters of this distribution is obtained. The results of processing experimental data are presented. We demonstrate that the proposed distribution is more consistent with the experimental data than the Pareto distribution.

Sign in / Sign up

Export Citation Format

Share Document