Simulation approach for achieving configuration independent poly-silicon gate etching

Profile and dimension control mechanisms in poly-silicon gate etching are studied systematically by the use of a two-dimensional etching topography simulator. Reaction rates are calculated by taking into account interactions between incoming ion/radical fluxes and an ever-changing macroscopic adsorbed particle layer on the film surface. A qualitative guideline is presented for achieving both anisotropic etched-profile formation and the dimension difference minimization between the inner line pattern and the outermost line pattern in L&S.