Physico-Chemical nanomaterials science
Effect of boron doping on temperature dependence of Raman spectra of boron doped HPHT-diamond
Danylenko I.M.1, Mozdalevskyi I.V.1,2, Nikolenko A.S.1, Strelchuk V.V.1, Starik S.P.3, Gontar O.G.3, Kovalenko T.V.3, Ivakhnenko S.O.3
1 V.E. Lashkaryov Institute of Semiconductor Physics NASU, pr. Nauky 41, 03028 Kyiv, Ukraine 
E-mail: igor.tesV@gmail.com
2 Taras Shevchenko National University of Kyiv, Faculty of Physics, Volodymyrska Street 64/13, 01601 Kyiv, Ukraine
3 V. Bakul Institute for Superhard Materials NASU, Avtozavodska str. 2, 04074 Kyiv, Ukraine

High hardness and stability of diamond, its excellent electrical and optical properties are of great importance for the development of the next generation of high-frequency and high power electronic devices. In particular, boron doped diamond (BDD) is of interest as p-type semiconductor. The dynamical behavior of optical phonons is important in terms of heat transfer, since electronic devices must efficiently dissipate heat to maintain operating temperatures. Temperature-dependent Raman spectroscopy is an effective non-contact method for measuring the temperature dependence of phonon lifetime. In this study, the effects of anharmonic decay (damping) of optical phonons in BDD are studied as a function of boron doping using micro-Raman spectroscopy through the modeling of temperature dependence of experimental phonon linewidth and frequency position. The type IIb BDD crystals with different level of boron doping were grown by the temperature gradient method under high pressure and high temperature (HPHT) in the Fe-Al-B-C system and multisectoral BDD plates of different orientation were prepared by laser cutting and mechanical polishing from. Undoped type IIa HPHT-diamond was studied for comparison. Micro-FTIR transmission spectroscopy was used to estimate the spatial distribution of uncompensated boron impurity [Na-Nd] in BDD plates through the analysis of boron-related absorption peaks. Theoretical modeling of temperature dependence of experimental phonon linewidth and frequency was performed in the temperature range of 78-373 K. Contributions of different mechanisms of anharmonic decay of optical phonons are considered. The predominant decay mechanisms and anharmonicity parameters of optical phonons are determined, which is of fundamental importance for the thermal conductivity of semiconductor materials.