28 August 2003 Measurement of hard pellicles for 157-nm lithography using Fourier transform phase-shifting interferometry
Author Affiliations +
Proceedings Volume 5130, Photomask and Next-Generation Lithography Mask Technology X; (2003) https://doi.org/10.1117/12.504217
Event: Photomask and Next Generation Lithography Mask Technology X, 2003, Yokohama, Japan
Though phase-shifting interferometry (PSI) is widely regarded as the method of choice for precision measurements of the surface and bulk characteristics of optical components, conventional PSI suffers from severe distortions in the presence of multiple reflections caused from co-parallel surfaces. The optical and physical characteristics of hard pellicles used for 157nm lithography mean that they are essentially parallel plates and the use of standard PSI techniques to evaluate the optical quality of these components will suffer from these problems. We describe a measurement method called Fourier Transform phase-shifting interferometry (FTPSI) that can overcome the disadvantages of standard PSI by the use of wavelength tuning and special analysis techniques. The technique can measure several surfaces simultaneously without distortion from multiple interference effects and is applied to the measurement of mounted and unmounted pellicles. Additionally, bulk properties of the pellicle, such as index homogeneity, can be easily measured with high precision. By spectrally separating the interference produced by different surfaces in the cavity during a wavelength chirp, each surface is identified and measured individually. In this paper, we describe the technique and give examples of measurements of hard pellicles provided by International SEMATECH.
© (2003) COPYRIGHT Society of Photo-Optical Instrumentation Engineers (SPIE). Downloading of the abstract is permitted for personal use only.
Leslie L. Deck, Chris Van Peski, Richard D. Eandi, "Measurement of hard pellicles for 157-nm lithography using Fourier transform phase-shifting interferometry", Proc. SPIE 5130, Photomask and Next-Generation Lithography Mask Technology X, (28 August 2003); doi: 10.1117/12.504217; https://doi.org/10.1117/12.504217


Influence of the pellicle on final photomask flatness
Proceedings of SPIE (May 20 2006)
157-nm lithography program at International SEMATECH
Proceedings of SPIE (August 01 2002)
New directions in image placement metrology
Proceedings of SPIE (April 01 2011)
Contamination control for ArF photo masks
Proceedings of SPIE (May 27 2009)
Photomask lifetime issues in ArF lithography
Proceedings of SPIE (June 28 2005)

Back to Top