Formation of Aligned α-Si3N4 Microfibers by Plasma Nitridation of Si (110) Substrate Coated with SiO2

Abstract

Plasma nitridation of an amorphous SiO2 layer on Si (110) substrate can form well-aligned α-Si3N4 crystallites in fibrous morphology. Nitriding is performed at a temperature in the range of 800–1000 °C by using microwave plasma with a gas mixture of N2 and H2. Raman spectroscopy shows the characteristics of an α-Si3N4 phase without other crystalline nitrides. As shown by scanning electron microscopy, the formed α-Si3N4 microfibers on the Si substrate can be in a dense and straight array nearly along with Si <11¯0>, and can have a length over 2 mm with a diameter in the range of 5–10 μm. Structural characterization of scanning transmission electron microscopy in cross section view reveals that the elongated α-Si3N4 crystallites are formed on the surface of the nitrided SiO2/Si (110) substrate without any interlayers between Si3N4 and Si, and the longitudinal direction of α-Si3N4 appears mainly along <112¯0>, which is approximately parallel to Si <11¯0>.

Utilization of Silicon Dust to Prepare Si3N4 Used for Steelmaking Additives: Thermodynamics and Kinetics

“…However, after nitriding, fibrous Si3N4 is produced at the f of its particles in Figure 4b. This is due to the fact that the surface oxide layer of the massive particles generates SiO gas and reacts with N2 to produce fibrous Si3N4.It is initially inferred that the different morphology of Si3N4 in Figure 4a,b is due to the different mechanism of nitriding [17,18], which will be discussed in detail below.…”

Effect of Rapid Thermal Annealing on Si-Based Dielectric Films Grown by ICP-CVD

“…These narrow peaks indicate the formation of Si nanocrystals − and nanocrystalline phases, α- and β-Si 3 N 4 . Formation of such phases occurs at normal pressure yet at high temperature . However, these requirements for nanocrystals can be relaxed .…”

“… 22 Formation of such phases occurs at normal pressure yet at high temperature. 30 However, these requirements for nanocrystals can be relaxed. 31 For example, α-Si 3 N 4 nanocrystals were registered in silicon oxynitride films deposited using ICP-CVD.…”