Plasma Etching of SiO2 Using Heptafluoropropyl Methyl Ether and Perfluoropropyl Vinyl Ether

Deaerated liquid acetaldehyde dimethyl acetal has been photolyzed at λ = 185 nm, and 28 products have been determined. The major ones with their quantum yields are: methanol (0.59), methane (0.26), ethyl methyl ether (0.17), methyl vinyl ether (0.16), methyl formate (0.14), ketene dimethyl acetal (0.1), ethane (0.06), hydrogen (0.06), and acetaldehyde (0.06).The major primary processes are suggested to be the scission of the C-OCH3 bonds (homolytic and molecular) and of the O-CH3 bonds (homolytic). Minor processes are hydrogen elimination reactions and the scission of the C-CH3 bond.

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Using the secondary electrons (SE) of SEM with NIST‘s MONSEL-II program to obtain improved linewidth measurements and slope angles of line edges on a MMIC GaAs device

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100167184 ◽

1996 ◽

Vol 54 ◽

pp. 944-945

Author(s):

Richard G. Sartore

Keyword(s):

Integrated Circuits ◽

Plasma Etching ◽

Microwave Integrated Circuits ◽

Monolithic Microwave Integrated Circuits ◽

Thick Gold ◽

Gaas Devices ◽

Source Distance ◽

Margin Of Error ◽

Dimensional Measurements ◽

Barrier Metal

In the evaluation of GaAs devices from the MMIC (Monolithic Microwave Integrated Circuits) program for Army applications, there was a requirement to obtain accurate linewidth measurements on the nominal 0.5 micrometer gate lengths used to fabricate these devices. Preliminary measurements indicated a significant variation (typically 10 % to 30% but could be more) in the critical dimensional measurements of the gate length, gate to source distance and gate to drain distance. Passivation introduced a margin of error, which was removed by plasma etching. Additionally, the high aspect ratio (4-5) of the thick gold (Au) conductors also introduced measurement difficulties. The final measurements were performed after the thick gold conductor was removed and only the barrier metal remained, which was approximately 250 nanometer thick platinum on GaAs substrate. The thickness was measured using the penetration voltage method. Linescan of the secondary electron signal as it scans across the gate is shown in Figure 1.

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Silicon layers grown over SiO2 by liquid phase epitaxy: Electron Microscopical study

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s042482010017596x ◽

1990 ◽

Vol 48 (4) ◽

pp. 566-567

Author(s):

F. Banhart ◽

F.O. Phillipp ◽

R. Bergmann ◽

E. Czech ◽

M. Konuma ◽

...

Keyword(s):

Electron Microscopy ◽

Liquid Phase ◽

Plasma Etching ◽

Liquid Phase Epitaxy ◽

Three Dimensional ◽

Microscopical Study ◽

Sample Temperature ◽

Structural Defects ◽

Si Substrates ◽

Etched Surface

Defect-free silicon layers grown on insulators (SOI) are an essential component for future three-dimensional integration of semiconductor devices. Liquid phase epitaxy (LPE) has proved to be a powerful technique to grow high quality SOI structures for devices and for basic physical research. Electron microscopy is indispensable for the development of the growth technique and reveals many interesting structural properties of these materials. Transmission and scanning electron microscopy can be applied to study growth mechanisms, structural defects, and the morphology of Si and SOI layers grown from metallic solutions of various compositions.The treatment of the Si substrates prior to the epitaxial growth described here is wet chemical etching and plasma etching with NF3 ions. At a sample temperature of 20°C the ion etched surface appeared rough (Fig. 1). Plasma etching at a sample temperature of −125°C, however, yields smooth and clean Si surfaces, and, in addition, high anisotropy (small side etching) and selectivity (low etch rate of SiO2) as shown in Fig. 2.

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A test of the effects of pregnenolone methyl ether on subjective feelings of B-29 crews after a twelve-hour mission.

PsycEXTRA Dataset ◽

10.1037/e429882004-001 ◽

1955 ◽

Author(s):

Saul B. Sells ◽

John R. Barry ◽

David K. Trites ◽

Herman I. Chinn

Keyword(s):

Methyl Ether

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Observations on a Relationship between Steroid Metabolism and the Concentration of Plasma Fibrinogen

Thrombosis and Haemostasis ◽

10.1055/s-0038-1654793 ◽

1963 ◽

Vol 10 (02) ◽

pp. 400-405 ◽

Cited By ~ 4

Author(s):

B. A Amundson ◽

L. O Pilgeram

Keyword(s):

Blood Coagulation ◽

Methyl Ether ◽

Broad Spectrum ◽

Human Subjects ◽

Plasma Fibrinogen ◽

Steroid Metabolism ◽

Specific Site ◽

Chain Reaction ◽

Normal Human ◽

A Chain

SummaryEnovid (5 mg norethynodrel and 0.075 mg ethynylestradiol-3-methyl ether) therapy in young normal human subjects causes an increase in plasma fibrinogen of 32.4% (P >C 0.001). Consideration of this effect together with other effects of Enovid on the activity of specific blood coagulatory factors suggests that the steroids are exerting their effect at a specific site of the blood coagulation and/or fibrinolytic system. The broad spectrum of changes which are induced by the steroids may be attributed to a combination of a chain reaction and feed-back control.

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Thermal gravimetric analysis of in-situ crosslinked nanocellulose whiskers • poly(methyl vinyl ether-co-maleic acid) • polyethylene glycol

TAPPI Journal ◽

10.32964/tj10.4.29 ◽

2011 ◽

Vol 10 (4) ◽

pp. 29-33

Author(s):

LEE A. GOETZ ◽

AJI P. MATHEW ◽

KRISTIINA OKSMAN ◽

ARTHUR J. RAGAUSKAS

Keyword(s):

Thermal Stability ◽

Polyethylene Glycol ◽

Vinyl Ether ◽

Thermal Gravimetric Analysis ◽

Maleic Acid ◽

Gravimetric Analysis ◽

Thermal Gravimetric ◽

Methyl Vinyl ◽

Methyl Vinyl Ether

The thermal stability and decomposition of in-situ crosslinked nanocellulose whiskers – poly(methyl vinyl ether-co-maleic acid) – polyethylene glycol formulations (PMVEMA-PEG), (25%, 50%, and 75% whiskers) – were investigated using thermal gravimetric analysis (TGA) methods. The thermal degradation behavior of the films varied according to the percent cellulose whiskers in each formulation. The presence of cellulose whiskers increased the thermal stability of the PMVEMA-PEG matrix.

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