Nickel monosilicide explained

Nickel monosilicide is an intermetallic compound formed out of nickel and silicon. Like other nickel silicides, NiSi is of importance in the area of microelectronics.

Preparation

Nickel monosilicide can be prepared by depositing a nickel layer on silicon and subsequent annealing. In the case of Ni films with thicknesses above 4 nm, the normal phase transition is given by Ni₂Si at 250 °C followed by NiSi at 350 °C and NiSi₂ at approximately 800 °C.^[1] For films with an initial Ni thickness below 4 nm a direct transition from orthorhombic Ni₂Si to epitaxial NiSi_2−x, skipping the nickel monosilicide phase, is observed.^[2]

Uses

Several properties make NiSi an important local contact material in the area of microelectronics, among them a reduced thermal budget, low resistivity of 13–14 μΩ·cm and a reduced Si consumption when compared to alternative compounds.^[3]

Notes and References

1. d'Heurle . F. M. . Gas . P. . February 1986 . Kinetics of formation of silicides: A review . Journal of Materials Research. 1 . 1 . 205–221 . 10.1557/JMR.1986.0205 . 1986JMatR...1..205D. 135724287 .
2. Wolf . Philipp M. . Pitthan . Eduardo . Zhang . Zhen . Lavoie . Christian . Tran . Tuan T. . Primetzhofer . Daniel . 2022-02-21 . Direct Transition from Ultrathin Orthorhombic Dinickel Silicides to Epitaxial Nickel Disilicide Revealed by In Situ Synthesis and Analysis . Small . 18 . 14 . en . 2106093 . 10.1002/smll.202106093. 35191181 . 247023770 . 1613-6810. free .
3. Lavoie . C. . d’Heurle . F.M. . Detavernier . C. . Cabral . C. . November 2003 . Towards implementation of a nickel silicide process for CMOS technologies . Microelectronic Engineering . 70 . 2–4 . 144–157 . 10.1016/S0167-9317(03)00380-0 .