Decoding Directional Control in Metal-Assisted Chemical Etching via Catalyst Architecture.

ABSTRACT: Metal-assisted chemical etching (MaCE) has emerged as a promising technique for fabricating silicon nanostructures, yet the presence of anomalous isotropic etching poses significant challenges for precise dimensional control. Here, it is demonstrated that catalyst morphology, particularly its aspect ratio, plays a crucial role in determining etching directionality. Through systematic investigation of the initial stages of MaCE, it is revealed that significant undercutting occurs within seconds of etching initiation, persisting across all solution compositions. This phenomenon is quantitatively analyzed using the Degree of Undercutting (DoU) and Degree of Anisotropy (DoA) metrics, establishing that conventional solution chemistry control alone cannot suppress lateral etching. These findings

SUBMITTER: Han Y 

PROVIDER: S-EPMC12272007 | biostudies-literature | 2025 Jul

REPOSITORIES: biostudies-literature