Published online by Cambridge University Press: 28 February 2011
A chemically assisted ion beam etching (CAIBE) technique is described which employs an ion beam from an electron bombardment ion source and a directed flux of ClF3 neutrals. This technique enables the etching of tungsten foils and films in excess of 40 μm thick with good anisotropy and pattern definition over areas 5 mm2, and with a high degree of selectivity. (100) tungsten foils etched with this process exhibit preferred orientation etching, while polycrystalline tungsten films exhibit high etch rates approximately 80% that of (100) orientation tungsten.