Platinum germanosilicide as source/drain contacts in P-channel fin field-effect transistors (FinFETs)

Abstract

In this paper, platinum germanosilicide (PtSiGe) was investigated extensively as an alternative to nickel germanosilicide (NiSiGe) for contact formation on silicon-germanium (SiGe) source/drain (S/D) stressors. We show that PtSiGe has superior thermal and morphological stability as compared to NiSiGe. Our results further show that the formation of PtSiGe yields a low hole barrier height ΦB P of 215 meV in a self-aligned process. We also demonstrated the integration of PtSiGe contacts in FinFET devices. FinFETs with PtSiGe contacts achieve a 27% reduction in external resistance (REXT compared to FinFETs with NiSiGe contacts. Statistical comparison reveals that the drive current performance is enhanced by 21% while maintaining comparable control of short-channel effects. These results illustrate the potential of forming contacts with low Schottky barrier heights using PtSiGe in strained transistors with SiGe S/D stressors, thereby reducing REXT and extending transistor performance. © 2009 IEEE.