Share Email Print

Proceedings Paper

Two-step modified NERIME process using combined focused ion beam lithography and plasma etching
Author(s): Khalil Arshak; Miroslav Mihov; Arous Arshak; Declan McDonagh; David Sutton; Simon B. Newcomb
Format Member Price Non-Member Price
PDF $17.00 $21.00

Paper Abstract

Focused ion beams (FIB) have been widely used as a patterning lithography technique for advanced ICs and optical masks fabrication. FIB lithography has certain advantages over the direct-write electron beam lithography in terms of resist sensitivity, backscattering and proximity effects. However, combining the FIB exposure with both Top Surface Imaging (TSI) and dry etching will further extend its advantages towards anisotropic processing of thicker resist layers in comparison to those used by the conventional lithography processes. The newly developed NERIME (Negative Resist Image by Dry Etching) process combines these advantages by the incorporation of focused Ga+ ion beam (Ga+ FIB) exposure, near UV exposure, silylation and dry etching. The work described here follows our investigations into the NERIME process for nanostructure applications and outlines a simplified (two-step) process incorporating FIB exposure and oxygen dry development. The two-step modified NERIME process is a negative working TSI system for DNQ/novolak based resists. Results show that Ga+ ion beam dose higher than 800μC/cm2 at 30keV can modify the exposed resist areas as to withstand the subsequent oxygen plasma etching, thus giving formation of negative resist image. In this study, nanometer resist patterns as small as 30nm with high aspect ratio of up to 15 were successfully resolved due to the high resolution ion beam exposure and anisotropic dry development. The proposed two-step lithography scheme could be utilized for the fabrication of critical CMOS process steps, such as sub-100nm gate formations and lithography over substantial topography.

Paper Details

Date Published: 15 October 2003
PDF: 11 pages
Proc. SPIE 5220, Nanofabrication Technologies, (15 October 2003); doi: 10.1117/12.503510
Show Author Affiliations
Khalil Arshak, Univ. of Limerick (Ireland)
Miroslav Mihov, Univ. of Limerick (Ireland)
Arous Arshak, Univ. of Limerick (Ireland)
Declan McDonagh, Integrated Devices Technology, Inc. (United States)
David Sutton, Univ. of Limerick (Ireland)
Simon B. Newcomb, Univ. of Limerick (Ireland)

Published in SPIE Proceedings Vol. 5220:
Nanofabrication Technologies
Elizabeth A. Dobisz, 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?