Rapid Thermal Oxidation of Silicon in Mixtures of Oxygen and Nitrous Oxide

1996 ◽  
Vol 429 ◽  
Author(s):  
John M. Grant ◽  
Zia Karim
Keyword(s):  
Nitric Oxide ◽  
Nitrous Oxide ◽  
Oxidation Kinetics ◽  
Atmospheric Pressure ◽  
Oxidation Rate ◽  
Molecular Nitrogen ◽  
Intermediate Species ◽  
Pressure Oxidation ◽  
Decomposition Of Nitrous Oxide ◽  
Wall Furnace

AbstractOxidation in nitrous oxide by conventional hot wall furnace processing and by rapid thermnal oxidation (RTO) has been a subject of much interest in recent years. RTO is a fundamentally different process than furnace oxidation, however, and the full effects of this type of processing on the oxidation kinetics are not well understood. Oxidation of silicon by RTO at a variety of pressures, temperatures, and oxidation gas mixtures has been studied. Although at lower temperatures (<850°C) the atmospheric pressure oxidation rate in nitrous oxide is very close to that in oxygen, at higher temperatures the oxidation rate in nitrous oxide is much lower than that in oxygen. At lower pressures in a RTO process, the oxidation rate in nitrous oxide is higher than that in oxygen. The effect of the nitrogen incorporated in the oxide acting as a diffusion barrier has been proposed as the mechanism of temperature dependence for atmospheric pressure oxidation in nitrous oxide. This does not explain the effects seen at lower pressures, however. We propose that some of the intermediate species produced in the decomposition of nitrous oxide into molecular nitrogen, molecular oxygen, and nitric oxide play a role in the initial stages of oxidation by RTO in nitrous oxide.

The Effect of Ge Segregation on Oxidation of Si

1987 ◽  
Vol 105 ◽  
Author(s):  
E. C. Frey ◽  
N. R. Parikh ◽  
M. L. Swanson ◽  
M. Z. Numan ◽  
W. K. Chu
Keyword(s):  
High Pressure ◽  
Low Temperature ◽  
Epitaxial Layer ◽  
Atmospheric Pressure ◽  
Oxidation Rate ◽  
Oxidation Temperature ◽  
Pressure Oxidation ◽  
Enhanced Oxidation ◽  
High Pressure Oxidation

AbstractWe have studied oxidation of various Si samples including: Ge implanted Si, CVD and MBE grown Si(0.4–4% Ge) alloys, and MBE grown Si-Si(Ge) superlattices. The samples were oxidized in pyrogenic steam (800–1000°C, atmospheric pressure) and at low temperature and high pressure (740°C, 205 atm of dry O2). The oxidized samples were analyzed with RBS/channeling and ellipsometry.An enhanced oxidation rate was seen for all Ge doped samples, compared with rates for pure Si. The magnitude of the enhancement increased with decreasing oxidation temperature. For steam oxidations the Ge was segregated from the oxide and formed an epitaxial layer at the Si-SiO2 interface; the quality of the epitaxy was highest for the highest oxidation temperatures. For high pressure oxidation the Ge was trapped in the oxide and the greatest enhancement in oxidation rate (>100%) was observed.

Role of Nitric Oxide in the Thermal Decomposition of Nitrous Oxide

1956 ◽  
Vol 25 (1) ◽  
pp. 106-115 ◽  
Author(s):  
Frederick Kaufman ◽  
Norman J. Gerri ◽  
Roger E. Bowman
Keyword(s):  
Nitric Oxide ◽  
Thermal Decomposition ◽  
Nitrous Oxide ◽  
Decomposition Of Nitrous Oxide

Temperature dependence of rate constants for the reactions of oxygen atoms, O(3P), with HBr and HI

1978 ◽  
Vol 56 (23) ◽  
pp. 2934-2939 ◽  
Author(s):  
D. L. Singleton ◽  
R. J. Cvetanović
Keyword(s):  
Nitric Oxide ◽  
Nitrous Oxide ◽  
Standard Deviation ◽  
Phase Shift ◽  
Rate Constants ◽  
Bond Energy ◽  
Bond Order ◽  
Shift Technique ◽  
Decomposition Of Nitrous Oxide ◽  
Oxygen Atoms

Rate constants for the reactions O(3P) + HX → OH + X (X = Br, I) have been determined by a phase shift technique. Oxygen atoms were generated by modulated mercury photosensitized decomposition of nitrous oxide, and were monitored by the chemiluminescence from the reaction with nitric oxide. Over the temperature interval 298–554 K, the rate constants are satisfactorily represented by the Arrhenius expressions kO+HBr = (8.09 ± 0.86) × 109 exp (−3.59 ± 0.08)/RT and kO+HI = (2.82 ± 0.27) × 1010 exp (−1.99 ± 0.07)/RT, where the units are ℓ mol−1 s−1 and kcal mol−1. The indicated uncertainties are one standard deviation. The results of bond energy–bond order calculations, incorporating recently proposed modifications, are discussed.

The thermal decomposition of nitrous oxide I. Secondary catalytic and surface effects

1955 ◽  
Vol 231 (1185) ◽  
pp. 162-178 ◽  
Keyword(s):  
Nitric Oxide ◽  
Thermal Decomposition ◽  
Nitrous Oxide ◽  
Surface Reaction ◽  
Order Rate Constant ◽  
Side Reactions ◽  
Chain Reactions ◽  
First Order ◽  
Reaction Vessels ◽  
Decomposition Of Nitrous Oxide

In the region of pressure 0 to 500 mrn approximately to the equation the thermal decomposition of nitrous oxide conforms approximately to the equation k = an /1 + a'n + bn , where k is the form al first-order rate constant, — (1/n) d n /d t , n the initial concentration and a, a' and b are nearly constant. Above about 100 m m this expression approximates to k = A + bn , which holds up to several atmospheres. Fresh and more detailed experiments have once again disproved the suggestion that the first term in these expressions is due to a surface reaction. (In certain states of reaction vessels, made of a particular brand of silica, a surface reaction may appear but is immediately recognizable by special criteria, and can be eliminated.) Detailed study of the formation of nitric oxide in the course of the decomposition, and of the effect of inert gas upon this process, shows that side reactions involving oxygen atoms, chain reactions and catalysis by nitric oxide play only minor parts in determining the shape of the k-n curve. The form of this curve, which is an inherent character of the reaction N 2 O = N 2 + O, raises theoretical questions of considerable interest.

Kinetics of the oxidation of ethane by nitric oxide over manganese(III) oxide

1981 ◽  
Vol 59 (14) ◽  
pp. 2232-2238
Author(s):  
R. A. Ross ◽  
C. Fairbridge
Keyword(s):  
Nitric Oxide ◽  
Carbon Dioxide ◽  
Nitrous Oxide ◽  
Atmospheric Pressure ◽  
Flow System ◽  
Oxide Formation ◽  
Catalyst Structure ◽  
X Ray ◽  
Apparent Activation Energies ◽  
Kinetics Of

The catalytic reaction between ethane and nitric oxide over manganese(III) oxide has been investigated in a continuous flow system from 673 to 573 K at atmospheric pressure. The products of catalysis were nitrogen, carbon dioxide, nitrous oxide, and water. The rate of nitrous oxide formation was constant over this temperature region, while the apparent activation energies for nitrogen and carbon dioxide formation increased from 32 ± 4 and 22 ± 4 kJ mol−1, respectively, at 573 to 613 K, to 78 ± 4 and 63 ± 4 kJ mol−1 between 613 and 673 K. The kinetic results were best described by the rate equation:[Formula: see text]The surface mechanism appears to be complex and has been interpreted by a scheme involving interaction of the reactants in an absorbed layer. Both nitric oxide and ethane are believed to be involved further in subsequent steps. Infrared evidence indicates the possibility of a surface nitrate intermediate consistent with the mechanistic proposal. Scanning electron microscopy and X-ray powder diffraction techniques were used to assess the catalyst structure.

THE EFFECT OF MOLECULAR OXYGEN ON THE REACTION OF OXYGEN ATOMS WITH cis-2-PENTENE

1959 ◽  
Vol 37 (5) ◽  
pp. 953-965 ◽  
Author(s):  
S. Sato ◽  
R. J. Cvetanović
Keyword(s):  
Nitric Oxide ◽  
Nitrous Oxide ◽  
Nitrogen Dioxide ◽  
Molecular Oxygen ◽  
Reaction Mechanisms ◽  
Room Temperature ◽  
Pressure Independent ◽  
Decomposition Of Nitrous Oxide ◽  
Oxygen Atoms

The effect of the presence of nitrogen, oxygen, and nitric oxide on the reaction between cis-2-pentene and oxygen atoms has been investigated at room temperature (25 ± 2 °C). For production of oxygen atoms use was made of mercury-photosensitized decomposition of nitrous oxide and of the photolysis of nitrogen dioxide at 3660 Å.In the N2O work, the presence of molecular oxygen induced the formation of acetaldehyde, propanal, methanol, and ethanol. In the NO2 work, the amounts of acetaldehyde, propanal, and ethyl nitrate formed increased rapidly with increasing pressure of molecular oxygen. Possible reaction mechanisms for the formation of these compounds are discussed.Additional information was obtained on the pressure-independent fragmentation in the reaction of oxygen atoms with cis-2-pentene.

Arrhenius parameters for the reactions of O(3P) atoms with several aldehydes and the trend in aldehydic C—H bond dissociation energies

1977 ◽  
Vol 55 (18) ◽  
pp. 3321-3327 ◽  
Author(s):  
D. L. Singleton ◽  
R. S. Irwin ◽  
R. J. Cvetanović
Keyword(s):  
Nitric Oxide ◽  
Nitrous Oxide ◽  
Ground State ◽  
Hydrogen Abstraction ◽  
Bond Dissociation Energies ◽  
Bond Dissociation ◽  
Dissociation Energies ◽  
Shift Technique ◽  
Decomposition Of Nitrous Oxide ◽  
Oxygen Atoms

The phase-shift technique has been used to determine the temperature dependence of the reaction of ground state oxygen atoms with several aldehydes. Oxygen atoms were generated by modulated photosensitized decomposition of nitrous oxide and were monitored by the chemiluminescence from their reaction with nitric oxide. The Arrhenius expressions determined over the temperature interval 298–472 K are: k1 (acetaldehyde) = (7.21 ± 1.49) × 109 exp (−1960 ± 153/RT); k1(propionaldehyde) = (7.78 ± 0.75) × 109 exp (−1727 ± 66/RT); k1(butyralde-hyde) = (9.99 ± 0.56) × 109 exp (−1702 ± 40/RT); k1(isobutyraldehyde) = (7.92 ± 1.02) × 109 exp (−1445 ± 91/RT), where the units are ℓ mol−1 s−1 and cal mol−1. The indicated uncertainties are one standard deviation. After small corrections were made for the potential abstraction of alkyl hydrogens, the activation energies of aldehydic hydrogen abstraction were used to estimate the aldehydic C—H bond dissociation energies, D(RCO—H). The trend of slightly decreasing values of D(RCO—H) thus obtained for the sequence H2CO, CH3CHO, C2H5CHO, n-C3H7CHO, i-C3H7CHO was also indicated by the aldehydic C—H stretching frequencies.

Emissions of nitrous oxide and nitric oxide associated with the decomposition of arable crop residues on a sandy loam soil in Eastern England

Agronomie ◽  
2002 ◽  
Vol 22 (7-8) ◽  
pp. 731-738 ◽  
Author(s):  
Roland Harrison ◽  
Sharon Ellis ◽  
Roy Cross ◽  
James Harrison Hodgson
Keyword(s):  
Nitric Oxide ◽  
Nitrous Oxide ◽  
Crop Residues ◽  
Sandy Loam ◽  
Sandy Loam Soil ◽  
Arable Crop ◽  
Loam Soil
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