Eur. Phys. J. Appl. Phys.
Volume 76, Number 3, December 2016
|Number of page(s)||12|
|Section||Instrumentation and Metrology|
|Published online||09 January 2017|
Analysis and detection of an incorrect profile shape in a classical scatterometric process
Univ. Lyon, UJM-Saint Etienne, LaHC, 42023 Saint-Etienne, France
2 Univ. Chad, LARTIC, INSTA, BP 6077, N’djamena, Chad
3 Univ. Grenoble, LTM, UMR CNRS 5129, 38054 Grenoble, France
a e-mail: firstname.lastname@example.org
Revised: 6 November 2016
Accepted: 18 November 2016
Published online: 9 January 2017
Scatterometry has become an efficient alternative method for subwavelength diffraction grating characterisation in semiconductor industries. It is based on the reconstruction of the periodic surface from its optical response. Ellipsometry seems to be a more powerful technique for optical measurement and neural networks has proved its effectiveness in the inverse scattering problem. However, in all cases, inverse characterisation processing needs a previously defined geometrical model. The aim of this works to study the impact of an incorrect profile shape in the characterization process and to measure the ability to detect it. Two type of neural network will be treated based respectively on a fixed trapezoidal profile and a generic one involving four different shapes. Theoretical results are presented for different simulated samples including several profile shapes. Experimental results are performed on a photoresist grating with a period of 140 nm on silicon substrate.
© EDP Sciences, 2016
Current usage metrics show cumulative count of Article Views (full-text article views including HTML views, PDF and ePub downloads, according to the available data) and Abstracts Views on Vision4Press platform.
Data correspond to usage on the plateform after 2015. The current usage metrics is available 48-96 hours after online publication and is updated daily on week days.
Initial download of the metrics may take a while.