Ion beam etching is a dry etch technique. The core part of an IBE system is a large diameter ion source. Gases enter the discharge chamber of the ion source and become ionized into a uniform plasma. The cations in the plasma are accelerated by the grids of the ion source, and subsequently neutralized by the neutralizer. The ion beam formed gains kinetic energy in the process, bombarding the sample surface and removes surface materials through physical sputtering. As a result, patterns are etched onto the samples. This purely physical process is usually conducted in relatively high vacuum.
The core strength of IBE systems is that the beam energy and ion flux can be independently controlled, since the plasma is formed remotely, away from the sample. Besides, the wafer holder can be tilted, altering the direction of impact and creating slanted features.