Quartz is reduced with carbon in a submerged-arc furnace: SiO2 + 2 C → Si + 2 CO at ~2000 °C. Semiconductor Si is made by the Siemens process: SiHCl3 vapor decomposes on hot (~1100 °C) Si rods.
Research Elements Si · atomic number 14 Metalloid · period 3, group 14 [Ne] 3s2 3p2 Shells: 2, 8, 4 Valence electrons: 4 in the outer shell (3s2 3p2) Green dots are the outer shell's s and p electrons. Softer green dots are the d electrons of transition metals, and the d and f electrons of lanthanides and actinides: they often take part in bonding, but not always. Grey dots are the core. Ground-state configuration from the NIST Atomic Spectra Database (A. Kramida, Yu. Ralchenko, J. Reader and the NIST ASD Team). Abundance is the mole fraction of the element found as that isotope on Earth; digits in parentheses are the uncertainty in the last digits. Masses and abundances from NIST, Atomic Weights and Isotopic Compositions (J. S. Coursey, D. J. Schwab, J. J. Tsai and R. A. Dragoset, National Institute of Standards and Technology).Silicon
Electrons
How it's obtained
Natural isotopes
Isotope Relative atomic mass Abundance How this isotope is separated 28Si 27.97692653465(44) 0.92223(19) Ultracentrifugation of gaseous SiF4, on the same principle as uranium enrichment: heavier isotopes migrate outward in a spinning rotor. Enriched SiF4 is reduced back to elemental Si by CVD onto a hot rod, and the boule is float-zoned to redistribute impurities. 29Si 28.97649466490(52) 0.04685(8) 30Si 29.973770136(23) 0.03092(11)