Improved contactless method of IR reflectance under grazing incidence for measurement of doping profiles

0501967 - FZÚ 2019 RIV BE eng C - Conference Paper (international conference)
Holovský, Jakub - Remeš, Zdeněk - Franta, D. - Conrad, B. - Abelová, Lucie - Bušek, D. - Poruba, Aleš
Improved contactless method of IR reflectance under grazing incidence for measurement of doping profiles.
Proceedings of 35th European Photovoltaic Solar Energy Conference and Exhibition. Brusel: WIP, 2018, s. 278-280. ISBN 3-936338-50-7.
[European Photovoltaic Solar Energy Conference and Exhibition /35./. Brusel (BE), 24.09.2018-28.09.2018]
R&D Projects: GA ČR GA18-24268S
Institutional support: RVO:68378271
Keywords : diffusion * characterisation * free-carrier absorption * in-Line * IR spectroscopy
OECD category: Condensed matter physics (including formerly solid state physics, supercond.)

We have elaborated contactless method of measurement and evaluation of doping profiles in silicon polished wafers based on infrared reflectance under high angle of incidence. We have found higher angle of incidence increases sensitivity, however approaching Brewster angle increases also experimental error, therefore 65 angle has been chosen. Moreover, to increase reproducibility we divide the measured spectra by reference spectra taken on an undoped sample, and further we rescale the spectra to fixed value in the region of 4000 cm-1–7000 cm-1. To reduce number of evaluated parameter, the carrier profile in boron-doped samples was parametrized by 3 parameters and that in phosphorous-doped samples was parametrized by 4 parameters, using additional empirically determined assumption that the first part of the profile is a constant plateau and that the following two exponential tails are joined at a value of 3x10^19 cm-3.

Permanent Link: http://hdl.handle.net/11104/0293938