Titanium Nitride Multilayer Deposition for Flat Narrow-Groove Films

The patent divides the film formation process into multiple sequential steps: first forming a titanium-containing film, then performing multiple alternating cycles of reducing gas supply and reactive gas supply. Each cycle creates a thin layer that contributes to flattening the surface while maintaining the barrier function. This segmented approach allows gradual surface refinement without compromising the underlying adhesion properties.

The patent employs periodic alternating supply of reducing gas and reactive gas in multiple cycles. The reducing gas step forms a metal-containing film, while the reactive gas step forms a compound film on its surface. This periodic action repeatedly builds and modifies thin layers, progressively flattening the titanium nitride film surface while maintaining its barrier functionality and adhesion properties.

The patent applies different gas supply conditions and process parameters specifically tailored for narrow groove structures. The multiple alternating cycles of reducing and reactive gas supply create locally optimized film deposition that adapts to the confined geometry, ensuring flat surface formation even in extremely narrow embeddings where conventional single-step processes would fail.

The patent performs preliminary surface preparation by forming a titanium-containing film first, then systematically building up and refining the surface through multiple reducing and reactive gas cycles before final tungsten deposition. This preliminary multi-step action ensures the surface is adequately flattened and prepared, creating a stable foundation for subsequent low-resistance tungsten film formation in narrow grooves.