Heat capacity of bulk boron-doped single-crystal HPHT diamonds in the temperature range from 2 to 400 K

Abstract

Heat capacity of bulk boron doped single crystal HPHT diamonds in the temperature range from 2 to 400 K Heat capacity С р of boron-doped single crystal diamonds grown by the temperature gradient method was studied. Boron content was about < 10 16 , ∼ 10 18 and ∼ 10 20 cm-3. Heat capacity data for all tested crystals match well within the measurement accuracy (1 %) in the temperature range of 150-400 K and obey the Debye law. At low temperatures heat capacity follows linear law possibly due to metallic inclusions in diamond bulk. Using this data the amount of metal can be calculated for each sample.

Effects of Boron Doping on the Bulk and Surface Acoustic Phonons in Single-Crystal Diamond

“…The dependence on the phonon group velocity is due to the phonon density of states. The previously reported data on the heat capacity of boron-doped single-crystal HPHT diamond support our arguments . In this study, the doped diamond samples with higher boron concentration revealed higher heat capacity.…”

“…In this study, the doped diamond samples with higher boron concentration revealed higher heat capacity. The authors have interpreted their observation as a possible inclusion of metallic particles during the growth process and thus the dominance of electron heat capacity at low temperatures . However, their data can also be explained by the lower phonon group velocity.…”

Low Temperature Thermal Conductivity of Heavily Boron-Doped Synthetic Diamond: Influence of Boron-Related Structure Defects

“…Such change of habits consistently takes place when boron content exceeds 10 19 cm -3 . More details of the growth process, electrical properties and heat capacity of sin-gle-crystal BDD were described in [11][12][13]. We used proprietary laser cut system to prepare (001) plates from grown crystals, and then mechanically polished them.…”

“…In [1][2][3][4] temperature dependencies of thermal conductivity of pure single crystal diamonds were measured and analyzed within the frameworks of Debye and Callaway models. The dominating role of phonon scattering on isotope 13 C atoms in thermal conductivity reduction has been deduced. Studies [1][2][3][4] showed that the thermal conductivity of diamond can be calculated using Callaway model [5] and the model parameters for normal and umklapp processes have been evaluated.…”

HFCVD Synthesis of Boron-Doped Microcrystalline Diamonds

“…Featured with high electrical conductivity, sound chemical stability and superior mechanical properties, the diamond doped with boron attracts researchers' interests in the field of structural material [10][11][12][13][14]. In addition to enormous researches focus on the superconducting properties of boron-doped diamond films and large single crystals [15][16][17], many efforts contribute to understanding their growth behaviors and morphology.…”