An experimental study of the etching of tungsten with SF6has been performed in a microwave multipolar plasma using an electron cyclotron resonance excitation with an independent low dc biasing. The anisotropy and etch rate of tungsten have been measured as a function of atomic fluorine concentration in the plasma and compared with silicon characteristics. The etching mechanisms of tungsten are analyzed in light of published data on the fluorine‐tungsten interaction, and the results are explained in terms of the diffusion model for plasma etching developed for the Si‐F system. Atomic fluorine adsorption on tungsten appears to be monolayerlike, whereas it is of multilayer type on silicon, and associative desorption of WF6occurs from WF3and/or WF4adspecies in nearest‐neighbor positions.