ScholarWorks@성균관대학교

초록

As the integration density of semiconductors is increased, the need for alternative interconnect materials to replace Cu has been growing in addition to the need of precise atomic scale etching of the materials. Mo is one of the candidates for next-generation interconnect materials, as it has lower apparent resistivity (electron mean free path × bulk resistivity; λ × ρ0) than Cu at critical dimension (CD) below 10 nm. In this study, an anisotropic atomic layer etching (ALE) process was performed by using Cl and O radicals for adsorption to form Mo compounds such as MoClx, MoOxCly, and MoOx, and by using Ar+ ions for desorption to etch the Mo compounds to achieve precise layer-by-layer etching. Based on this ALE process, precise etching was achieved with an etch depth per cycle (EPC) of ∼0.9 Å/cycle under Cl2 adsorption conditions, with a wide ALE window and low physical and chemical damage, and a EPC of ∼0.3 Å/cycle under Cl2 + O2 adsorption conditions, with high selectivity to TiN. © 2025

키워드