Atomic Layer Etching of Si(100) and Si(111) Using Cl[sub 2] and Ar Neutral Beam

Atomic layer etching of Si(100) and Si(111) was carried out using adsorption followed by the Ar neutral beam irradiation for the removal of charging damage during the etching. By supplying and Ar neutrals higher than the critical doses, the exact same depth per cycle corresponding to one atomic layer per cycle of for silicon (100) and for silicon (111) could be obtained by a self-limited etching mechanism. The critical pressure and Ar neutral beam irradiation time corresponded to one monolayer chemisorption of chlorine by the dissociative Langmuir isotherm and the irradiation of Ar neutral beam was enough to remove one layer of silicon chloride formed on the silicon surfaces, respectively.