DOI: 10.1063/1.3297902. Variable-wavelength frequency-domain terahertz ellipsometry

Variable-wavelength frequency-domain terahertz ellipsometry

10.1063/1.3297902

Crossref journal-article

AIP Publishing

Review of Scientific Instruments (317)

Abstract

We report an experimental setup for wavelength-tunable frequency-domain ellipsometric measurements in the terahertz spectral range from 0.2 to 1.5 THz employing a desktop-based backward wave oscillator source. The instrument allows for variable angles of incidence between 30° and 90° and operates in a polarizer-sample-rotating analyzer scheme. The backward wave oscillator source has a tunable base frequency of 107–177 GHz and is augmented with a set of Schottky diode frequency multipliers in order to extend the spectral range to 1.5 THz. We use an odd-bounce image rotation system in combination with a wire grid polarizer to prepare the input polarization state. A highly phosphorous-doped Si substrate serves as a first sample model system. We show that the ellipsometric data obtained with our novel terahertz ellipsometer can be well described within the classical Drude model, which at the same time is in perfect agreement with midinfrared ellipsometry data obtained from the same sample for comparison. The analysis of the terahertz ellipsometric data of a low phosphorous-doped n-type Si substrate demonstrates that ellipsometry in the terahertz spectral range allows the determination of free charge-carrier properties for electron concentrations as low as 8×1014 cm−3.

Bibliography

Hofmann, T., Herzinger, C. M., Boosalis, A., Tiwald, T. E., Woollam, J. A., & Schubert, M. (2010). Variable-wavelength frequency-domain terahertz ellipsometry. Review of Scientific Instruments, 81(2).

Authors 6

T. Hofmann (first)
C. M. Herzinger (additional)
A. Boosalis (additional)
T. E. Tiwald (additional)
J. A. Woollam (additional)
M. Schubert (additional)

References 51 Referenced 80

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Dates

Type	When
Created	15 years, 6 months ago (Feb. 3, 2010, 6:39 p.m.)
Deposited	2 years, 1 month ago (July 3, 2023, 9:35 p.m.)
Indexed	22 hours, 43 minutes ago (Aug. 27, 2025, noon)
Issued	15 years, 6 months ago (Feb. 1, 2010)
Published	15 years, 6 months ago (Feb. 1, 2010)
Published Online	15 years, 6 months ago (Feb. 2, 2010)
Published Print	15 years, 6 months ago (Feb. 1, 2010)

Funders 0

None

BibTeX

@article{Hofmann_2010, title={Variable-wavelength frequency-domain terahertz ellipsometry}, volume={81}, ISSN={1089-7623}, url={http://dx.doi.org/10.1063/1.3297902}, DOI={10.1063/1.3297902}, number={2}, journal={Review of Scientific Instruments}, publisher={AIP Publishing}, author={Hofmann, T. and Herzinger, C. M. and Boosalis, A. and Tiwald, T. E. and Woollam, J. A. and Schubert, M.}, year={2010}, month=feb }

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