Parameters in a plasma etcher can be varied by power, pressure, process time, reactant gas flow, flow ratio of reactants, and temperature. The reactive species in plasma etching systems are important.

The following is a list of requirements for the reactive species:

• High selectivity for etching the desired substrate material and not the masking material
• High plasma etching rate for the substrate material
• Good etching uniformity

The pressure of the plasma etcher controls the quantity of ions and free radicals in the chamber.

The radio frequency (RF) power input should be chosen in order to obtain the largest etch rate and to minimize undesired etching of other materials.