Mechanism of incipient oxidation of bulk chemical vapor deposited Si[sub 3]N[sub 4]

Journal Article · Mon Mar 01 04:00:00 EST 1993 · Journal of the Electrochemical Society; (United States)

DOI:https://doi.org/10.1149/1.2056154· OSTI ID:6399054

Ogbuji, L U.T. ^[1]; Jayne, D T ^[2]

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1. NASA, Cleveland, OH (United States) Sverdrup Technology Inc., Cleveland, OH (United States)
2. NASA, Cleveland, OH (United States) Case Western Reserve Univ., Cleveland, OH (United States)

X-ray photoelectron spectroscopy was employed, in conjunction with ion bombardment, to analyze the chemical composition profile across thin (< 50 nm) oxide films on chemically vapor deposited Si[sub 3]N[sub 4]. The thermal oxides were grown in dry oxygen at 1,100 C on samples with or without native oxide film (formed in room air). The results show that the thermal oxidation product was silicon oxynitride of graded N:O ratio, and that the presence of a native oxide film promoters the formation of a SiO[sub 2] crust over the oxynitride. It is proposed that the fundamental mechanism of Si[sub 3]N[sub 4] oxidation is progressive O-for-N substitution in the silicon oxynitride unit tetrahedron, which is best designated SiN[sub 2[minus]x]O[sub 2+x], where x is also an index of depth. The corresponding equation for nonstoichiometric oxidation of Si[sub 3]N[sub 4] describes a bulk (rather than an interface) reaction process, with significant implications for O[sub 2] and N[sub 2] fluxes and diffusivities.

• OSTI ID: 6399054
• Journal Information: Journal of the Electrochemical Society; (United States), Journal Name: Journal of the Electrochemical Society; (United States) Vol. 140:3; ISSN JESOAN; ISSN 0013-4651
• Country of Publication: United States
• Language: English

Related Subjects

36 MATERIALS SCIENCE
360205* -- Ceramics
Cermets
&amp; Refractories-- Corrosion &amp; Erosion
BEAMS
CHALCOGENIDES
CHEMICAL COATING
CHEMICAL COMPOSITION
CHEMICAL REACTION KINETICS
CHEMICAL REACTIONS
CHEMICAL VAPOR DEPOSITION
DEPOSITION
ELECTRON SPECTROSCOPY
ION BEAMS
KINETICS
NITRIDES
NITROGEN COMPOUNDS
OXIDATION
OXIDES
OXYGEN COMPOUNDS
PHOTOELECTRON SPECTROSCOPY
PNICTIDES
REACTION KINETICS
SILICON COMPOUNDS
SILICON NITRIDES
SILICON OXIDES
SPECTROSCOPY
SURFACE COATING
X-RAY SPECTROSCOPY