A novel silicide and germanosilicide by NiCo alloy for Si and SiGe source/drain contact with improved thermal stability

Abstract

NiCo (10 at.% of Co) alloy was employed in the formation of metal silicide and germanosilicide as the contact layer which can be used as future complementary metal–oxide–semiconductor source/drain contact. The resistivity and structure evolution of NiCo silicide and germanosilicide were investigated, and the performance of the NiCo silicide is better than conventional NiSi and comparable with NiPt silicides, as well as NiPt germanosilicide below 700 °C. The thermal stability and enhanced sheet resistance of NiCo silicide and germanosilicide were found to be up to 900 °C and 700 °C, respectively. The low sheet resistance at high temperature was attributed to the low-temperature CoSi by enhancing the thermal stability and uniformity of the Ge. The influence of Ge concentration was studied in different Si_1−xGe_x substrates, and the low sheet resistance can be reliable up to 650 °C.