Optical constants for 2 variants of silicon-germanium (SiGe) from 80 eV - 250 eV

In our newest publication (open access) we present a method comparison of EUV reflectometry and STEM-EDX on stacked thin-film samples. As a side product, we determined the optical constants of two SiGe materials with ~20% and ~40% germanium content.

Ciesielski, R., Bogdanowicz, J., Loo, R., Shimura, Y., Mani, A., Mitterbauer, C., ... & Soltwisch, V. (2024). Interface sharpness in stacked thin film structures: a comparison of soft X-ray reflectometry and transmission electron microscopy. Journal of Micro/Nanopatterning, Materials, and Metrology, 23(4), 041405-041405.

https://doi.org/10.1117/1.JMM.23.4.041405

Welcome! This is ocdb, a Python package for easily accessing the X-ray/EUV/VUV scattering and absorption data contained in the Optical Constants Database (OCDB) provided by the German National Metrology Institute, the Physikalisch-Technische Bundesanstalt, PTB.

Features

A list of (planned) features:

• Access to X-ray/EUV/VUV scattering and absorption coefficients (n and k)
• Interface compatible to the periodictable Python package
• Provides data and uncertainties
• FAIR and linked data: citable, reliable, and reproducible
• Offline access: data contained in package
• Community-driven: easy to contribute

And to make it even more convenient for users and future-proof:

• Open source project written in Python (>= 3.9)
• Developed fully test-driven
• Extensive user and API documentation

Ru n&k from 8.0 nm - 23.75 nm

Time-frequency analysis assisted determination of ruthenium optical constants in the sub-EUV spectral range 8 nm – 23.75 nm

Qais Saadeh et al. 2021

https://doi.org/10.1364/OE.426029

Ta n&k from 5 nm - 24 nm

Nested Sampling aided determination of tantalum optical constants in the EUV spectral range

Qais Saadeh et al. 2022

https://doi.org/10.1364/AO.472556

Updated figure for quick overview over the 13.5nm optical constants. Current optical constants published in the following journal papers:

• Saadeh, Qais et al. Optics Express 29.25 (2021): 40993-41013.
• Andrle, Anna et al. Journal of Applied Crystallography 54.2 (2021): 402-408.
• Saadeh, Qais et al Applied Optics 61.33 (2022): 10032-10042.
• Ciesielski, Richard et al. Applied Optics 61.8 (2022): 2060-2078.
• Saadeh, Qais et al. Optical Materials Express 13.1 (2023): 78-91.
• Saadeh, Qais et al. Optik 273 (2023): 170455.
   

Optical constants for TaCo
Reconstructed from reflection measurements in the wavelength range 8 - 22 nm

Tunability of the optical constants of tantalum-cobalt alloy thin films in the extreme ultraviolet  Optical Materials Express Vol. 13, Issue 1, pp. 78-91 (2023)

Qais Saadeh, Vicky Philipsen, Devesh Thakare, Philipp Naujok, Meiyi Wu, Frank Scholze, Christian Buchholz, Claudia Tagbo-Fotso, Ayhan Babalik, Bettina Kupper, and Victor Soltwisch

https://doi.org/10.1364/OME.474887

Co n&k from 8 nm - 25 nm

On the optical constants of cobalt in the M-absorption edge region

Qais Saadeh et al. 2023

https://doi.org/10.1016/j.ijleo.2022.170455

Added Quartz n&k data 45 eV to 620 eV.

A. Andrle et al. J. Appl. Cryst. (2021). 54, 402-408 https://doi.org/10.1107/S1600576720016325
Quartz Data https://zenodo.org/record/4118056

launch of the website ocdb.ptb.de

Mo, Ni, Pt, Ru, Ta, Te,  Ni₂ Al₃, Ni₃ Al, NiAl, Pt₂Mo, PtMo, PtTe, RuTa, Ru₃Ta, Ru₃Re, Ru₃W, TaBN, TaTeN

Publication https://doi.org/10.5281/zenodo.5607168
Full data set: doi.org/10.5281/zenodo.5602719