Determination of boron concentration in diamond from Raman spectroscopy

This tool has been developed for the determination of boron concentration ([B]) in heavily doped diamond ([B] > 5 x 1019 cm-3) using non-destructive Raman measurements. It is based on the analysis of the two characteristic Raman peaks located at ca. 1200 cm-1 and 1330 cm-1 attributed respectively to the Fano-shaped maximum of phonon density of states and zone-centre phonon line of heavily boron-doped diamond [1]. The model makes a reasonable assumption of a linear Electronic Raman scattering “background” over the analysed wavenumber range (1000 – 1500 cm-1) [2]. The fitting function is described below. The program does not take into account any potential additional peaks due to other forms of non-diamond carbon. More details on the analysis of the Raman spectrum of heavily boron-doped diamond and the determination of boron concentration of epitaxial diamond layers can be found in references [2-4]

\[I(\omega) = (B_1\omega + B_2)\times(\sum_{i}^nA_i \cfrac{q_i+{(\cfrac{\omega-\omega_i}{\Gamma_i})}^2} {1+{(\cfrac{\omega-\omega_i}{\Gamma_i})}^2}+C)\]

This fitting tool is simple and should be used as described below. A demonstration video is available here. The fitting process is fast and all parameters are changeable. In case fitting is not accurate, you may obtain a better fit by changing the boundaries of the fitting parameters or by changing the wavenumber analysis range. The outputs of the program are all fitting parameters and the boron concentration determined from the unperturbed width of the diamond ZCP peak (parameter “G2”) according to ref. [1]. Raw data is not corrected for temperature and spectral response of the spectrometer, as it is assumed not to be necessary over the narrow range under investigation. The intensity is normalized (i.e. divided by its maximum value) prior to the fitting process.

  1. Load the Raman data (The data file must be in csv format without any headings).

  2. Use the mouse to define the fitting wavenumber analysis range.

  3. Choose the type of parameters (Automatic, user defined…).

  4. Press Analyze data.

This program has been developed at FZU - Institute of Physics of the Czech Academy of Sciences by Ing. M. Lamac, Ing. N. Lambert, Msc. L. Iwanikov and Dr. V. Mortet and financially supported by the Czech Science Foundation (grant number 17-05259S)

[1] V. Mortet et al., Insight into boron-doped diamond Raman spectra characteristic features, Carbon 115 (2017) 279-284. (https://doi.org/10.1016/j.carbon.2017.01.022)

[2] V. Mortet et al., Determination of atomic boron concentration in heavily boron-doped diamond by Raman spectroscopy, Diamond and Related Materials 93 (2019) 54-58. (https://doi.org/10.1016/j.diamond.2019.01.028)

[3] V. Mortet et al., New perspectives for heavily boron-doped diamond Raman spectrum analysis, Carbon 168 (2020) 319-327. (https://doi.org/10.1016/j.carbon.2020.06.075)

[4] Analysis of heavily boron-doped diamond Raman spectrum, Diamond and Related Materials 88 (2018) 163-166. (https://doi.org/10.1016/j.diamond.2018.07.013)