Application of Mueller matrix spectroscopic ellipsometry to determine line edge roughness on photomasks

A. Heinrich; I. Dirnstorfer; J. Bischoff; U. Richter; H. Ketelson; K. Meiner; T. Mikolajick

doi:10.1117/12.2030627

1 October 2013 Application of Mueller matrix spectroscopic ellipsometry to determine line edge roughness on photomasks

A. Heinrich, I. Dirnstorfer, J. Bischoff, U. Richter, H. Ketelson, K. Meiner, T. Mikolajick

Author Affiliations +

Proceedings Volume 8886, 29th European Mask and Lithography Conference; 88860L (2013) https://doi.org/10.1117/12.2030627
Event: 29th European Mask and Lithography Conference, 2013, Dresden, Germany

Abstract

We report on Mueller Matrix spectroscopic ellipsometry (MM-SE) to examine undesired asymmetries in structural parameters, i.e. line edge roughness (LER). The investigation was done on a photomask containing line space arrays with intentionally modulated line edges. The Mueller Matrix (MM) elements were measured within the complete azimuth angle range (0 - 360°) and a wavelength range from 300 nm to 980 nm. The results are presented in polar coordinates with the azimuth angle and wavelength as the angular and radial coordinate, respectively. It was found that LER significantly impacts the MM elements, which is indicated by the increase of the isotropic character of the array. The experimental data are confirmed by Rigorous Coupled Wave Analysis (RCWA) simulations on perturbed arrays. Based on RCWA the impact of LER amplitudes in the nm range is determined. It was found that both deviation of critical dimension (CD) and LER amplitude impact the MM elements. Based on the intensity ratios of the elements and their spectral distribution both errors create a characteristic finger print, which allows to separate them. Finally, the required measurement precision for LER in the nm range is estimated at 0.001. This precision is challenging but achievable with today’s metrology.

Citation Download Citation

A. Heinrich, I. Dirnstorfer, J. Bischoff, U. Richter, H. Ketelson, K. Meiner, and T. Mikolajick "Application of Mueller matrix spectroscopic ellipsometry to determine line edge roughness on photomasks", Proc. SPIE 8886, 29th European Mask and Lithography Conference, 88860L (1 October 2013); https://doi.org/10.1117/12.2030627

ACCESS THE FULL ARTICLE

INSTITUTIONAL
Select your institution to access the SPIE Digital Library.

SELECT YOUR INSTITUTION

PERSONAL
Sign in with your SPIE account to access your personal subscriptions or to use specific features such as save to my library, sign up for alerts, save searches, etc.

PERSONAL SIGN IN

No SPIE Account? Create one

;

PURCHASE THIS CONTENT

SUBSCRIBE TO DIGITAL LIBRARY

50 downloads per 1-year subscription

Members: $195

Non-members: $335 ADD TO CART

25 downloads per 1 - year subscription

Members: $145

Non-members: $250 ADD TO CART

PURCHASE SINGLE ARTICLE