Controlling Etch Anisotropy of Crystalline Germanium Nanostructures.

ABSTRACT: Orientation-dependent wet chemical etching of crystalline germanium (c-Ge) is essential for the fabrication of next-generation complementary metal oxide semiconductor (CMOS) devices. Here, using a combination of conventional and in situ liquid-phase transmission electron microscopy (TEM) imaging, we reveal the details of the wet etching process of c-Ge nanostructures and identify critical parameters that control the etching rates along different crystalline directions. We demonstrate that etching behavior can be changed from isotropic to anisotropic etching (i.e., from crystal-orientation-independent to orientation-dependent etching) by introducing hydrochloric acid (HCl) into a commonly used hydrogen peroxide (H₂O₂) etchant. The observations reveal that the relative

SUBMITTER: Saidov K 

PROVIDER: S-EPMC12508700 | biostudies-literature | 2025 Oct

REPOSITORIES: biostudies-literature