Structural Analysis of Si(OEt)4 Deposits on Au(111)/SiO2 Substrates at Nanometer Scale using Focused Electron Beam Induced Deposition

TL;DR

This study investigates the nanometer-scale composition and structure of Si(OEt)4 deposits on Au(111)/SiO2 substrates created via focused electron beam induced deposition, revealing how age and conditions affect composition.

Contribution

It provides detailed analysis of Si(OEt)4 FEBID deposits at nanometer scale, highlighting the effects of aging and deposition parameters on composition and morphology.

Findings

C content decreases from over 60% to below 50% with deposit aging.

High-rate, low-temperature deposition yields Si content of 10-15%.

Au(111) substrate influences deposit composition and shape due to its surface properties.

Abstract

The focused electron beam induced deposition (FEBID) process was used by employing a Gemini SEM with a beam characteristic of 1keV and 24pA for the deposition of pillars and line shaped deposits with heights between 9nm to 1um and widths from 5nm to 0.5um. All structures have been analyzed to their composition looking at a desired Si : O : C content of 1: 2 : 0. The C content of the structure was found to be ~over 60% for older deposits kept in air (~at room temperature) and less than 50% for younger deposits, only 12 hours old. Using a deposition of Si(OEt)4 at high rates and a deposition temperature of under 0 degC, an Si content of our structure between 10at% and 15at% (compositional percentage) was obtained. The FEBID structures have been deposited on Au(111) over an SiO2 wafer. The Au(111) was chosen as a substrate for the deposition of Si(OEt)4 due to its structural and morphological properties, with its surface granulation following a Chevron pattern, and the Au(111) defects having a higher contribution to the change in the composition of the final content of the structure with the increase in O ratio and a reduction in the shapes heights.