Ion beam transfer of fine mechanical patterns into cemented carbide chips

In this paper we describe the fabrication of dies for electrical devices and fine mechanical parts by transferring mask patterns into cemented carbide chips. Mechanical masks were made from tungsten wires. The pattern transfer into cemented carbide chips, with grain size of 2-3 μm and of 0.5 μm, and binderless grains, was performed using a Kaufman-type ion beam machining apparatus. The surface roughness of the cemented carbide chips increased rapidly to the same machined depth as their grain size and increased more slowly after that in proportion to the ion beam machined depth. The surface of cemented carbide chips machined at lower ion incidence angles (more nearly parallel to the surface) was also roughened more rapidly than the surface those machined at higher angles (more nearly perpendicular to the surface). Fine-grained cemented carbide chips with a size of 0.5 μm, machined with 1.0 keV argon ions at changing ion incident angles, exhibited smooth surfaces. The chips may be useful as a substrate for mechanical parts and dies, and tungsten wire may be also useful as a mask material for ion beam etching. The transferred dies have good pattern profiles.