Interactions between binary metallic alloys and Si, GeSi and GaAs

Thin film interactions for ternary systems (metalmetalSi and metalGeSi) and quaternary systems (metalmetalGaAs and metalmetalGeSi) are reviewed in this paper. Interactions between silicon and metal alloys are classified into Sisolid solutions, Siamorphous phases and Siintermetallic compounds. Different reaction behaviors for these three categories and their respective applications are discussed. The outcomes of the reaction are analyzed using knowledge from binary silicide formation, solid solubilities of binary silicides and metalmetal interactions. For GaAs, emphasis is placed on thermal stabilities of different metallization schemes. Both amorphous alloys and intermetallic compounds are considered. The metalGeSi reactions are illustrated using specific examples and the results are explained based on data obtained from binary silicide and germanide formation. The energetically more favorable metalSi reaction than the metalGe reaction often causes composition changes in GeSi, thus thermally stable contacts are addressed.