Issue 5, 2020

Metal assisted chemical etching of silicon in the gas phase: a nanofabrication platform for X-ray optics

Abstract

High aspect ratio nanostructuring requires high precision pattern transfer with highly directional etching. In this work, we demonstrate the fabrication of structures with ultra-high aspect ratios (up to 10 000 : 1) in the nanoscale regime (down to 10 nm) by platinum assisted chemical etching of silicon in the gas phase. The etching gas is created by a vapour of water diluted hydrofluoric acid and a continuous air flow, which works both as an oxidizer and as a gas carrier for reactive species. The high reactivity of platinum as a catalyst and the formation of platinum silicide to improve the stability of the catalyst pattern allow a controlled etching. The method has been successfully applied to produce straight nanowires with section size in the range of 10–100 nm and length of hundreds of micrometres, and X-ray optical elements with feature sizes down to 10 nm and etching depth in the range of tens of micrometres. This work opens the possibility of a low cost etching method for stiction-sensitive nanostructures and a large range of applications where silicon high aspect ratio nanostructures and high precision of pattern transfer are required.

Graphical abstract: Metal assisted chemical etching of silicon in the gas phase: a nanofabrication platform for X-ray optics

Supplementary files

Article information

Article type
Communication
Submitted
11 11 2019
Accepted
17 2 2020
First published
17 2 2020
This article is Open Access
Creative Commons BY-NC license

Nanoscale Horiz., 2020,5, 869-879

Metal assisted chemical etching of silicon in the gas phase: a nanofabrication platform for X-ray optics

L. Romano, M. Kagias, J. Vila-Comamala, K. Jefimovs, L. Tseng, V. A. Guzenko and M. Stampanoni, Nanoscale Horiz., 2020, 5, 869 DOI: 10.1039/C9NH00709A

This article is licensed under a Creative Commons Attribution-NonCommercial 3.0 Unported Licence. You can use material from this article in other publications, without requesting further permission from the RSC, provided that the correct acknowledgement is given and it is not used for commercial purposes.

To request permission to reproduce material from this article in a commercial publication, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party commercial publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.

Social activity

Spotlight

Advertisements