Investigation of the Shadow Effect in Focused Ion Beam Induced Deposition

Abstract

Due to the precursor gas flow in the focused ion beam induced deposition process, a shadow effect appears behind the shading structures. This article carries out experiments with phenanthrene as the precursor gas and establishes a numerical model to define the shadow area and estimate the intensity of the shadow effect, considering the morphology of shading structure, the beam shift, and the nozzle parameters. Within the shadow area, the precursor molecule adsorption contribution is estimated by calculating the fraction of precursor gas flow in a specific direction. Finally, the number of precursor molecules within the beam impact area influenced by the shadow effect is obtained, emphasizing the important role of gas surface diffusion. The adsorption contribution within the shadow area differs a lot while deposited structures are similar in height. The error between the simulation and the experimental results is about 5%, verifying the accuracy of the proposed model.

Pillar Growth by Focused Electron Beam-Induced Deposition Using a Bimetallic Precursor as Model System: High-Energy Fragmentation vs. Low-Energy Decomposition

“…For the final shape and cross-sectional evolution in the as-deposited FEBID wires, the direction of the gas injection system [21]. shadowing effects [22] and beam parameters [19] have to be considered and carefully tuned to achieve the highest shape fidelities. Furthermore, the influence of beam currents on crystallinity and purity has been described.…”

Cationic Defect-Modulated Li-Ion Migration in High-Voltage Li-Metal Batteries

“…Typically, 3D hosts exhibit complex nanostructures. Building blocks with different 3D skeleton morphologies show line-of-sight self-shadowing, hindering the movement of the Li + -ion flux into the shadow region behind the supported network; this causes a predominant deposition of Li on the top surface of the support. ,, …”

“…Building blocks with different 3D skeleton morphologies show line-of-sight self-shadowing, hindering the movement of the Li + -ion flux into the shadow region behind the supported network; this causes a predominant deposition of Li on the top surface of the support. 19,21,22 Significant electrical interactions in 3D host scaffolds enable the charged surface of the host to undergo strong electrostatic interactions; this facilitates the efficient adhesion and homogeneous distribution of the Li + -ion flux, minimizing adverse morphology Li-metal deposition. Oxygen vacancies have been used to generate local electric fields on the Li-host surface to modulate electrical ordering and manipulate the migration of Li + ions under Coulombic forces.…”