Fifty centimeter ion beam sourcea

A 50‐cm‐diam ion source and its industrial applications are described. This is the largest commercial ion source presently available for ion beam etching and deposition over a full 20 in. diam. It has been used to generate beams of argon ions at 300–900 eV of ion energy and beam currents of 1–5 A with standard filament‐type cathodes. Operation at even higher current levels is possible with high emissivity hollow cathodes. A presentation of general performance characteristics of the ion source is given and some of the special considerations required for reliable and cost‐effective operation of large scale ion beam systems are discussed. To illustrate the application of this source, a brief description of a fully automatic production ion beam etching system developed around this ion source is given along with a description of the etch results. This system can simultaneously etch a batch of five 6‐in.‐diam wafers with etch rates of nickel–iron exceeding 500 A/min. The etch uniformity is excellent.