Characterization of the Cu/barrier metal interface for copper interconnects

Thermal stress and reliability characterization of barriers for Cu interconnects

“…Second set of samples with blanket PVD Cu(10-2Onm)/ barrier film on blanket PECVD Si@ substrates were prepared and these samples were baked in a vacuum chamber at 35OC for 15min. These were then observed for Cu film agglomeration using the SEM to evaluate the Cu wetting property [3]. A third set of samples with blanket ECP Cu (1.3p)PVD Cu(2OOnm)/barrier films on blanket PECVD Si@ substrates were prepared to evaluated stress hysteresis and Cu to Cu barrier adhesion [4,5].…”

Highly >111< textured Cu film formation on CVD-TiN film by Ti underlayer and Ar sputter etch for damascene interconnection

“…Sputtered Ta and TaN films are usually used as barrier layers for Cu interconnection, because high wetting and highly (1 1 1)-oriented texture of Cu films are obtained by using them as underlayers (2). Though MOCVD-TIN film has an advantage of good step coverage, it is well-known that .cl 11> texture and wetting of Cu films on the CVD-TIN films are poorer than those on the Ta and TaN films (2,3). To improve EM endurance of CuICVD-TiN interconnection, wetting and <111> texture of Cu films must be improved.…”

“…It is well known that high wetting and highly (111)-oriented texture of Cu films are effective to enhance electromigration (EM) endurance in Cu damascene interconnection (1)(2)(3)(4). Sputtered Ta and TaN films are usually used as barrier layers for Cu interconnection, because high wetting and highly (1 1 1)-oriented texture of Cu films are obtained by using them as underlayers (2).…”