Diamonds are for everyone

Man-made diamonds – manufactured by chemical vapour deposition (CVD) – are grown in carbon-containing gas in a plasma state. Layers of carbon atoms create stones chemically identical to mined diamonds

Microwave plasma chamber
Magnetron (microwave source)
Tuner to adjust frequency
Gas inlet Methane and hydrogen precursors
Chamber
Vacuum Gas pressures in range of 30-300 Torr – between 4% and 39% of
one standard atmosphere

Waveguide

Sliding short-circuit Positions location of plasma above pedestal
Window
Plasma  Fourth state of matter, after solids, liquids and gas. Temperature 700-1000°C
Pedestal 

High supersaturation 99% hydrogen to 1% methane gas
H2 CH4
Diamond wafers act as seed crystals
Pedestal
Plasma
Carbon atoms are deposited on diamond wafers Diamond used for industrial applications or gems



Sources: De Beers Element Six, Diamond Materials, Cardiff University     © GRAPHIC NEWS