Detection of Two Highly Stable Silicon Nitrides: HSiNSi and H3SiNSi

• Published in: The journal of physical chemistry. A, Molecules, spectroscopy, kinetics, environment, & general theory Vol. 117; no. 44; pp. 11282 - 11288
• Main Authors: Crabtree, Kyle N, Martinez, Oscar, McCarthy, Michael C
• Format: Journal Article
• Language: English
• Published: Washington, DC American Chemical Society 07.11.2013
• Subjects: Atomic and molecular physics; Exact sciences and technology; Molecular properties and interactions with photons; Molecular spectra; Physics; Radio-frequency and microwave spectra; Inorganic free radical; Electric discharges; Rotational transition; Silicon nitride; Theoretical study; Gas mixtures; CVD; Polyatomic molecules; Hyperfine structure; Molecular beams; Gas phase; Microwave spectra; Formation mechanism
• ISSN: 1089-5639; 1520-5215; 1520-5215
• DOI: 10.1021/jp4068119

The formation mechanisms of silicon nitride and silicon nitrogen hydrogen films, both produced by chemical vapor deposition (CVD) techniques and widely used in electronic device fabrication, are poorly understood. Identification of gas-phase intermediates formed from starting materials, typically silane, ammonia, and/or nitrogen, is a critical step in assessing the interplay between gas and surface processes in film formation. Two potential intermediates in this process, HSiNSi and H3SiNSi, have now been detected in a molecular beam by means of rotational spectroscopy. Both molecules were produced in electrical discharges of CVD-like gas mixtures and are the most readily observed silicon–nitrogen-containing molecules in the 6–20 GHz frequency range, though neither has been the subject of prior experimental or theoretical studies. HSiNSi and H3SiNSi are likely formed from reactions involving the silanitrile radical (SiN, isoelectronic to CN), implying that similar gas-phase reactions may be involved in film growth.