FORMATION OF A LARGE GRAIN SIZED TIN LAYER USING TINX, THE EPITAXIAL CONTINUITY AT THE AL/TIN INTERFACE, AND ITS ELECTROMIGRATION ENDURANCE IN MULTILAYERED INTERCONNECTION

A new technique on the formation of TiN film with large grain size from TiNx is described. The TiNx layer (defined in Sec. II A) was deposited by sputtering in argon and nitrogen. The nitrogen atoms in Ti matrix relaxed the mechanical stress of the deposited him and limited the surface mobility during the deposition process, resulting in a nanocrystalline structure with extremely uniform thickness. After rapid thermal annealing (RTA), the TiNx yielded a bilayer structure of TiN/TiSixOy, in which the TiN showed (111) preferred texture, extremely smooth surface, and large grain size without any columnar structure. In addition, the resistivity of the bilayered TiN was as low as 40 mu Omega cm. In the TiN multilayered aluminum structure (i.e., TiN/Al/TiN), epitaxial continuity and the intermetallic compound such as TiAl3 were clearly observed at the aluminum/TiN interface. The multilayered structure showed better endurance against EM in comparison with the same structure using the conventional TiN (also defined in Sec. II A). (C) 1995 American Institute of Physics.