TaSi2

TaSi2, or tantalum disilicide, is a binary intermetallic compound composed of tantalum and silicon with the formula TaSi2. It forms in the tantalum–silicon system and can be generated by high-temperature reaction of tantalum with silicon or by depositing Ta and Si followed by annealing to promote TaSi2 formation. The compound is notable for its thermal stability and for its metallic-like electrical conductivity, which makes it relevant for high-temperature electronic applications.

Crystal structure and phase relations of TaSi2 have been studied in bulk and thin-film forms. The bulk material is reported to crystallize in a well-defined intermetallic lattice, with structural details that can vary with preparation method and impurities. In the Ta–Si phase diagram, TaSi2 exists alongside other tantalum silicides such as Ta5Si3, and its stability is temperature- and composition-dependent. Thin-film TaSi2 often shows orientation and microstructure that depend on substrate choice and deposition conditions.

Preparation and processing considerations are important for its use in devices. TaSi2 can be produced by solid-state diffusion at elevated temperatures or by co-deposition of Ta and Si with subsequent annealing. In microelectronics, TaSi2 is formed at silicon interfaces by annealing tantalum on silicon or by co-sputtering Ta and Si, yielding a silicide layer that adheres to silicon and can provide a low-resistivity contact.

Applications and relevance: TaSi2 has been investigated as a diffusion barrier and contact material in silicon-based electronics, where its stability at silicon interfaces and electrical conductivity are advantageous. Its role is often considered alongside other tantalum silicides in strategies for silicon diffusion control and silicide formation.