Share Email Print

Proceedings Paper

High-aspect ratio silicon structures by displacement Talbot lithography and Bosch etching
Author(s): Konstantins Jefimovs; Lucia Romano; Joan Vila-Comamala; Matias Kagias; Zhentian Wang; Li Wang; Christian Dais; Harun Solak; Marco Stampanoni
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Despite the fact that the resolution of conventional contact/proximity lithography can reach feature sizes down to ~0.5- 0.6 micrometers, the accurate control of the linewidth and uniformity becomes already very challenging for gratings with periods in the range of 1-2 μm. This is particularly relevant for the exposure of large areas and wafers thinner than 300 μm. If the wafer or mask surface is not fully flat due to any kind of defects, such as bowing/warpage or remaining topography of the surface in case of overlay exposures, noticeable linewidth variations or complete failure of lithography step will occur. We utilized the newly developed Displacement Talbot lithography to pattern gratings with equal lines and spaces and periods in the range of 1.0 to 2.4 μm. The exposures in this lithography process do not require contact between the mask and the wafer, which makes it essentially insensitive to surface planarity and enables exposures with very high linewidth uniformity on thin and even slightly deformed wafers. We demonstrated pattern transfer of such exposures into Si substrates by reactive ion etching using the Bosch process. An etching depth of 30 μm or more for the whole range of periods was achieved, which corresponds to very high aspect ratios up to 60:1. The application of the fabricated gratings in phase contrast x-ray imaging is presented.

Paper Details

Date Published: 27 March 2017
PDF: 7 pages
Proc. SPIE 10146, Advances in Patterning Materials and Processes XXXIV, 101460L (27 March 2017); doi: 10.1117/12.2258007
Show Author Affiliations
Konstantins Jefimovs, Paul Scherrer Institut (Switzerland)
ETH Zürich (Switzerland)
Lucia Romano, Paul Scherrer Institut (Switzerland)
ETH Zürich (Switzerland)
Univ. degli Studi di Catania (Italy)
Joan Vila-Comamala, Paul Scherrer Institut (Switzerland)
ETH Zürich (Switzerland)
Matias Kagias, Paul Scherrer Institut (Switzerland)
ETH Zürich (Switzerland)
Zhentian Wang, Paul Scherrer Institut (Switzerland)
ETH Zürich (Switzerland)
Li Wang, Eulitha AG (Switzerland)
Christian Dais, Eulitha AG (Switzerland)
Harun Solak, Eulitha AG (Switzerland)
Marco Stampanoni, Paul Scherrer Institut (Switzerland)
ETH Zürich (Switzerland)

Published in SPIE Proceedings Vol. 10146:
Advances in Patterning Materials and Processes XXXIV
Christoph K. Hohle, Editor(s)

© SPIE. Terms of Use
Back to Top
Sign in to read the full article
Create a free SPIE account to get access to
premium articles and original research
Forgot your username?