Corrections Thermogravimetric Study of Magnesium and Aluminum Metal-Gas Reactions

Studying the behavior of surfaces at high temperatures is of great importance for understanding the properties of ceramics and associated surface-gas reactions. Atomic processes occurring on bulk crystal surfaces at high temperatures can be recorded by reflection electron microscopy (REM) in a conventional transmission electron microscope (TEM) with relatively high resolution, because REM is especially sensitive to atomic-height steps.Improved REM image resolution with a FEG: Cleaved surfaces of a-alumina (012) exhibit atomic flatness with steps of height about 5 Å, determined by reference to a screw (or near screw) dislocation with a presumed Burgers vector of b = (1/3)<012> (see Fig. 1). Steps of heights less than about 0.8 Å can be clearly resolved only with a field emission gun (FEG) (Fig. 2). The small steps are formed by the surface oscillating between the closely packed O and Al stacking layers. The bands of dark contrast (Fig. 2b) are the result of beam radiation damage to surface areas initially terminated with O ions.

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Residual Gas Reactions in the Electron Microscope: I. Qualitative Observations on the Water Gas Reaction

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100101207 ◽

1968 ◽

Vol 26 ◽

pp. 292-293

Author(s):

Richard E. Hartman ◽

Roberta S. Hartman ◽

Peter L. Ramos

Keyword(s):

Electron Beam ◽

Electron Microscope ◽

Gas Phase ◽

Absolute Temperature ◽

Residual Gas ◽

Gas Reactions ◽

Image Position ◽

The Right ◽

Water Gas ◽

Thinning Rate

The action of water and the electron beam on organic specimens in the electron microscope results in the removal of oxidizable material (primarily hydrogen and carbon) by reactions similar to the water gas reaction .which has the form:The energy required to force the reaction to the right is supplied by the interaction of the electron beam with the specimen.The mass of water striking the specimen is given by:where u = gH2O/cm2 sec, PH2O = partial pressure of water in Torr, & T = absolute temperature of the gas phase. If it is assumed that mass is removed from the specimen by a reaction approximated by (1) and that the specimen is uniformly thinned by the reaction, then the thinning rate in A/ min iswhere x = thickness of the specimen in A, t = time in minutes, & E = efficiency (the fraction of the water striking the specimen which reacts with it).

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Thermogravimetric Study of Coal Vitrinites at Different Metamorphic Stages in the Oxidizing Medium

Химия в интересах устойчивого развития ◽

10.15372/khur20180213 ◽

2018 ◽

Keyword(s):

Thermogravimetric Study

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Thermogravimetric study of barium titanate

10.31274/rtd-180813-4315 ◽

1973 ◽

Author(s):

James Nicholas Lingscheit

Keyword(s):

Barium Titanate ◽

Thermogravimetric Study

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Latch-Up Induced Slit Voiding in Aluminum Metal Lines

ISTFA 1999: Conference Proceedings from the 25th International Symposium for Testing and Failure Analysis ◽

10.31399/asm.cp.istfa1999p0145 ◽

1999 ◽

Author(s):

Chunyu Zhang ◽

Lakshmi Vedula ◽

Shekhar Khandekar

Keyword(s):

High Temperature ◽

Line Width ◽

Fold Increase ◽

Metal Line ◽

Operating Life ◽

Mixed Signal ◽

Aluminum Metal ◽

Temperature Operating ◽

Latch Up

Abstract Latch-up induced during High Temperature Operating Life (HTOL) test of a mixed signal device fabricated with 1.0 μm CMOS, double poly, double metal process caused failures due to an open in aluminum metal line. Metal lines revealed wedge voids of about 50% of the line width. Triggering of latch up mechanism during the HTOL test resulted in a several fold increase of current flowing through the ground metal line. This increase in current resulted in the growth of the wedge voids leading to failures due to open metal lines.

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