Investigation of Ultrathin Ni Germanosilicide for Advanced pMOS Contact Metallization

Abstract

Ultrathin Ni germanosilicide liner ( x Ge y /p+-SiGe:B contacts show improved specific contact resistivity ( $\rho _{\text {c}}$ ) with respect to conventional TiSi x Ge y /p+-SiGe:B ones. It is further demonstrated that the $\rho _{\text {c}}$ of NiSi x Ge y /p+-SiGe:B contacts is correlated with both Ni thickness and post metal anneal (PMA). Utilizing Ge preamorphization implant (Ge PAI) followed by B ion implant (B I/I), the active concentration of B dopants is enhanced from $1\times 10^{{20}}$ cm $^{-{3}}$ for reference to $6\times 10^{{20}}$ cm $^{-{3}}$ . Consequently, a remarkably lowered $\rho _{\text {c}}$ of $\sim 7.42\times 10^{-{9}} \,\Omega \cdot $ cm2 is achieved for NiSi x Ge y /p+-SiGe:B contacts, where Ni layer is 20 A and PMA temperature is 500 °C.