Anisotropic reactive ion etching of titanium

The reactive ion etching of titanium is described using rf discharges of CCl4 and O2 with additions of fluorine containing gases. Because of these additions the titanium etch rate increases substantially in comparison with the pure CCl4/O2 plasma. This is presumably due to a shift of equilibrium reactions within the discharge towards the production of the volatile etch product. Process parameters are given for which the reactive ion etching of titanium with a photoresist mask is highly anisotropic and an etch end point control by optical emission spectroscopy is possible.