Top-down fabrication of diamond nanostructures.

Diamond nanostructures can have exciting applications in electronics and thermal management, but their controlled fabrication can be challenging. Here, we present a top-down approach for the fabrication of diamond nanorod (DNR) clusters, via use of metal masks (Al, Ag, Au, and Cr) and reactive-ion etching (RIE). Prolonged RIE on Ag and Cr masks yields distinct etching profiles, and DNR clusters are selectively formed from Ag masks, with individual nanorods having dimensions of ∼100 nm diameter and ∼ 1.5 μm length. Detailed electron microscopy shows thin layer of amorphous carbon (a-C) around single crystalline DNR cores. Chemical analyses also show presence of oxygen on the surface of the DNRs. Fabrication of the DNR clusters with scalable top-down approach could lead to new nanodiamond-based applications. [Display omitted] • Our study presents a top-down approach for fabricating diamond nanorod (DNR) clusters. • We uncover responses of different metal masks (Al, Ag, Au, and Cr) to plasma etching, providing valuable insights for optimizing fabrication processes. • In-situ decomposition of bulk Ag into nanoparticles during reactive-ion etching (RIE), facilitates controlled DNR formation. • Through detailed microscopic analyses, we characterize the morphology and composition of DNR clusters. [ABSTRACT FROM AUTHOR]