Copper silicide
Copper silicide (Cu5Si), also called pentacopper silicide, is a binary compound of silicon with copper. It is an intermetallic compound, meaning that it has properties intermediate between an ionic compound and an alloy. This solid crystalline material is a silvery solid that is insoluble in water. It forms upon heating mixtures of copper and silicon.
Identifiers | |
---|---|
ECHA InfoCard | 100.032.066 |
PubChem CID |
|
CompTox Dashboard (EPA) |
|
Properties | |
Cu5Si | |
Molar mass | 345.8155 g/mol |
Appearance | silver powder |
Melting point | 825 °C (1,517 °F; 1,098 K) |
Hazards | |
NIOSH (US health exposure limits): | |
PEL (Permissible) |
TWA 1 mg/m3 (as Cu)[1] |
REL (Recommended) |
TWA 1 mg/m3 (as Cu)[1] |
IDLH (Immediate danger) |
TWA 100 mg/m3 (as Cu)[1] |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
Infobox references | |
Applications
Copper silicide thin film is used for passivation of copper interconnects, where it serves to suppress diffusion and electromigration and serves as a diffusion barrier.[2]
Copper silicides are invoked in the Direct process, the industrial route to organosilicon compounds. In this process, copper, in the form of its silicide, catalyses the addition of methyl chloride to silicon. An illustrative reaction affords the industrially useful dimethyldichlorosilane:[3]
- 2 CH3Cl + Si → (CH3)2SiCl2
References
- NIOSH Pocket Guide to Chemical Hazards. "#0150". National Institute for Occupational Safety and Health (NIOSH).
- "Archived copy". Archived from the original on 2007-09-29. Retrieved 2007-02-10.CS1 maint: archived copy as title (link)
- Greenwood, Norman N.; Earnshaw, Alan (1997). Chemistry of the Elements (2nd ed.). Butterworth-Heinemann. ISBN 978-0-08-037941-8.