Corrosion Susceptibility of Mesoporous Carbons: Evidential Understanding of the Effects of Quasi-Passive Oxide Formation

2021 ◽  
Vol MA2021-02 (6) ◽  
pp. 541-541
Author(s):  
Manila Ozhukil Valappil ◽  
Farisa Forouzandeh ◽  
Marwa Atwa ◽  
Samantha Luong ◽  
Viola Ingrid Birss
Author(s):  
M. Park ◽  
S.J. Krause ◽  
S.R. Wilson

Cu alloying in Al interconnection lines on semiconductor chips improves their resistance to electromigration and hillock growth. Excess Cu in Al can result in the formation of Cu-rich Al2Cu (θ) precipitates. These precipitates can significantly increase corrosion susceptibility due to the galvanic action between the θ-phase and the adjacent Cu-depleted matrix. The size and distribution of the θ-phase are also closely related to the film susceptibility to electromigration voiding. Thus, an important issue is the precipitation phenomena which occur during thermal device processing steps. In bulk alloys, it was found that the θ precipitates can grow via the grain boundary “collector plate mechanism” at rates far greater than allowed by volume diffusion. In a thin film, however, one might expect that the growth rate of a θ precipitate might be altered by interfacial diffusion. In this work, we report on the growth (lengthening) kinetics of the θ-phase in Al-Cu thin films as examined by in-situ isothermal aging in transmission electron microscopy (TEM).


Author(s):  
Fumio Watari ◽  
J. M. Cowley

STEM coupled with the optical system was used for the investigation of the early oxidation on the surface of Cr. Cr thin films (30 – 1000Å) were prepared by evaporation onto the polished or air-cleaved NaCl substrates at room temperature and 45°C in a vacuum of 10−6 Torr with an evaporation speed 0.3Å/sec. Rather thick specimens (200 – 1000Å) with various preferred orientations were used for the investigation of the oxidation at moderately high temperature (600 − 1100°C). Selected area diffraction patterns in these specimens are usually very much complicated by the existence of the different kinds of oxides and their multiple twinning. The determination of the epitaxial orientation relationship of the oxides formed on the Cr surface was made possible by intensive use of the optical system and microdiffraction techniques. Prior to the formation of the known rhombohedral Cr2O3, a thin spinel oxide, probably analogous to γ -Al203 or γ -Fe203, was formed. Fig. 1a shows the distinct epitaxial growth of the spinel (001) as well as the rhombohedral (125) on the well-oriented Cr(001) surface. In the case of the Cr specimen with the (001) preferred orientation (Fig. 1b), the rings explainable by spinel structure appeared as well as the well defined epitaxial spots of the spinel (001). The microdif fraction from 20A areas (Fig. 2a) clearly shows the same pattern as Fig. Ia with the weaker oxide spots among the more intense Cr spots, indicating that the thickness of the oxide is much less than that of Cr. The rhombohedral Cr2O3 was nucleated preferably at the Cr(011) sites provided by the polycrystalline nature of the present specimens with the relation Cr2O3 (001)//Cr(011), and by further oxidation it grew into full coverage of the rest of the Cr surface with the orientation determined by the initial nucleation.


1999 ◽  
Vol 09 (PR8) ◽  
pp. Pr8-65-Pr8-72 ◽  
Author(s):  
A. E. Turgambaeva ◽  
V. V. Krisyuk ◽  
A. F. Bykov ◽  
I. K. Igumenov
Keyword(s):  

1996 ◽  
Vol 451 ◽  
Author(s):  
Gerald S. Frankel

ABSTRACTCorrosion of thin film structures commonly used in electronic and magnetic devices is discussed. Typical failure modes are presented, and galvanic corrosion is discussed in some detail since it is one common problem with such devices. A graphical explanation for the determination of the ohmic potential drop during galvanic corrosion is presented. The corrosion problem of thin film disks is shown to have changed during the past ten years owing to changes in disk structure. The corrosion susceptibility of two antiferromagnetic alloys used for exchange coupling to soft magnetic layers is discussed.


Diabetes ◽  
1992 ◽  
Vol 41 (4) ◽  
pp. 552-556 ◽  
Author(s):  
J. A. Corbett ◽  
R. G. Tilton ◽  
K. Chang ◽  
K. S. Hasan ◽  
Y. Ido ◽  
...  

Author(s):  
И.В. Коваленко ◽  
М.А. Чубинский ◽  
Д.С. Русаков ◽  
Г.С. Варанкина

Применение древесины осины в промышленном производстве материалов и изделий ограничено из-за ее низких механических свойств, подверженности поражению коррозионно-деструктивной гнили, отсутствием должного обоснования технологии ее переработки. Невостребованная осина осложняет условия хозяйствования в лесу, ухудшает породный состав древостоев, препятствует восстановлению хвойных пород древесины. Древесина осины хуже смачивается водой по сравнению с другими породами. Изучение ее поверхностных свойств и строения на микроуровне представляет безусловный интерес для изучения взаимодействия древесины с водой, жидкими клеящими и защитно-декоративными веществами. Это сложная многопараметрическая задача, решение которой может явиться новым инструментом для обоснования наукоемких технологических процессов сушки, пропитки, склеивания и облагораживания древесины. Истинная поверхность древесины, образованная в результате обработки резанием (лущением, пилением, фрезерованием) значительно больше ее проекции на плоскости в результате разрезания микроструктурных элементов. Неровности на поверхности искажают результаты измерения поверхностных свойств, определяемых на основе угла смачивания. Учитывая то, что размеры стенок клеток меньше размеров полостей, истинная площадь поверхности древесины, в зависимости от вида разреза, может в десятки раз превышать кажущуюся. Ухудшение способности смачиваться объясняет образование на поверхности капель клея, нанесенного на шпон методом вальцевания. При горячем прессовании фанеры в первый момент времени повышается подвижность молекул клея, снижается упругость древесины, поверхность выравнивается, улучшая условия адгезионного взаимодействия связующего и древесины. Для определения истинных характеристик древесины, обоснования расхода клея, способности древесины поглощать жидкость необходимо знать размеры ее микроструктурных элементов и характер их распределения, объем поверхностных полостей. Эффективный радиус полостей древесины осины может быть описан с использованием теории фракталов. The use of aspen wood in manufacturing of materials and products is limited due to its low mechanical properties, corrosion susceptibility destructive lesion decay, its lack of proper justification processing technology. Unclaimed aspen difficult economic conditions in the forest, degrades the species composition of forest stands and prevents restoration of softwood. Wood aspen worse moistened with water compared to other breeds. The study of its structure and surface properties at the micro level is of great interest to study the interaction of wood with water, liquid adhesives and protective-decorative materials. This is the problem whose solution can be a new tool for the study of science-intensive technological processes of drying, impregnation, gluing and surface finishes. Real wood surface, formed by the machining (peeling, sawing, milling) significantly greater its projection on the plane as a result of cutting the microstructural elements. Surface irregularities distort the results of measurement of surface properties which are determined based on the contact angle. Given that the size of the cell walls is less than the size of the cavities, the true surface area of the veneer, depending on the type of incision, may be ten times the apparent. The deterioration of the ability of wetted explains the formation of droplets on the surface of adhesive deposited on the veneer by rolling. When plywood hot pressing at a first time increases mobility of adhesive molecules, decreases the modulus of elasticity of wood, surface is aligned, improving the conditions of interaction of the glue and the wood. To determine the true characteristics of the wood, glue flow study, the ability of wood to absorb liquid it is necessary to know the size of microstructural elements and their distribution, the amount of surface cavities. The effective radius of aspen wood cavities can be described using fractal theory.


Sign in / Sign up

Export Citation Format

Share Document