LPCVD silicon nitride layers can be easily deposited on silicon wafers in a reproducible, pure and uniform way. This leads to silicon nitride layers with low electrical conductivity, very good coverage of edges and high thermal stability.
PECVD silicon nitride layers allow higher growth rate, which therefore leads to thicker layers. Stoichiometry and stress can also be adjusted. High thickness uniformity and etch rates are eventually obtained. PECVD Silicon nitride wafers are particularly suitable for passivation layers.
In the field of tool-making, stoichiometric trisilicon tetranitride (Si3N4) with its very high mechanical and thermal stability is used for tools such as roller bearings used under harsh conditions.
For semiconductor devices, the chemical, electrical and optical properties of amorphous hydrogenated silicon nitride (SiNx) make this material well-suited for different applications, such as for
passivation or insulating layers in integrated circuits
masking or etch stop material in wet and plasma etching processes due to its high chemical stability
masking material in silicon oxidation processes due to the very low oxygen diffusion coefficient in SiNx
anti-reflective coating in photovoltaics due to its adjustable refractive index