Dry etching method and apparatus

摘要

An accurate dry etching technique is described that employs a flow of neutral radicals and a light beam. A dry etching apparatus 50 employs a neutral radical flow source 20 and a light beam 40 to irradiate a flow of neutral radicals 32, so that the velocity component of the neutral radicals parallel to the surface of an object to be etched 12 is reduced, and etches anisotropically the object to be etched, while the object 12 is exposed to the radical flow 32 whose parallel velocity component is decreased. The invention reduces the problem of etching parallel to the substrate while etching perpendicular to the substrate to improve anisotropic dry etching without any adverse or damage producing effect to dielectric or semiconductor layers due to ions.