Tunable n-Type Conductivity and Transport Properties of Cubic Boron Nitride via Carbon Doping

Abstract

The recent discovery of direct conversion of hexagonal boron nitride (h-BN) into quenched BN (Q-BN) and single-crystal cubic BN (c-BN) by pulsed laser annealing (PLA) have been implemented to fabricate carbon-doped c-BN with dopant concentration ranging from 2 × 10 19 to 7 × 10 21 cm −3 . Micro Raman analysis shows a total conversion of h-BN into phase-pure c-BN, whereas the X-ray diffraction (XRD) confirms the presence of the cubic structure with (111) epitaxy on c-sapphire. Hall measurements demonstrate the n-type electrical property, and the temperature-dependent resistivity measurements confirm the semiconductor-like profile of the doped c-BN. Consistent changes in resistivity, Hall mobility, and other electrical properties were investigated with the variance in dopant concentration level. We have observed a shift in the conduction mechanism with temperature from the resistivity vs temperature analyses. At the hightemperature regime (130−330 K), the activation energy lies in between 0.012 and 0.074 eV, whereas at the low-temperature regime (20−130 K), the activation energy was obtained to be in between 0.0024 and 0.0083 eV. The lower values of activation energies, showing a complete ionization of the impurity atoms even at room temperature, are surmised to result from dopant-profile broadening. The enhanced electrical activation and superior quality c-BN films open exciting avenues for next-generation device applications.

Small Electron Polaron in Carbon-Doped Cubic Boron Nitride

“…We note that, for a given concentration of carbon dopants (number of carbon dopants per supercell), there are several ways to divide the carbon at nitrogen and boron sites. Since the experimental samples are n-doped, we only consider configurations with scriptN normalB ≥ scriptN normalN namely, C B (1.5% doping) (and C N for reference), 2 C B (3%), C B C N (3%), 2 C B 1 C N (4.7%), 2 C B 2 C N (6.25%), 3 C B 1 C N (6.25%), 3 C B 2 C N (7.8%), and 4 C B 1 C N (7.8%). Also, under N-rich conditions, the formation energies of C B and C N substituents were shown to be comparable, with a slight preference for the formation of the former defect than for the latter one .…”

“…The temperature dependent resistivity measurements by Haque et al . show two regimes in carbon-doped cBN: (i) a high temperature regime (≥35 K) with higher activation energies and resistivity decreasing with temperature and (ii) a low temperature regime (<35 K) where the resistivity increases with a decrease in temperature with a lower activation energy.…”

“…Cubic boron nitride (cBN) is known for its stability and an ultrawide band gap of 6.1 eV, qualities that enable its use in applications demanding extreme pressures and temperatures and high power. − Notwithstanding numerous reports of successful n-doping ,, and p-doping − of cBN since the late 1980s, doping it controllably and reliably with the precision required for optoelectronics applications had proved to be difficult over the decades. Recent advances in experimental techniques, in particular pulsed laser deposition, has allowed Haque et al to controllably n-dope cBN using up to 5% carbon (C), a concentration about 100 times higher than the thermodynamic solubility limit of 0.08%. These high doping levels open up new possibilities for the use of cBN in electronic and optical high-power applications.…”

Superior p‐Type Surface Doping of Cubic Boron Nitride via MoO3 Adsorption

“…[3] The p-type c-BN has been generally achieved by doping with beryllium (Be), magnesium, zinc, and the n-type c-BN is obtained by doping with silicon (Si), sulfur, and carbon. [1,4] Importantly, the p-n junction diodes were successfully fabricated by DOI: 10.1002/adts.202100460 growing Si-doped c-BN films on Be-doped c-BN seed crystals. [5] Despite these progress, it is arduous to control growths of pure c-BN crystals and dope the material with the desirable carrier concentrations and mobilities.…”

Polymer-Assisted Dispersion of Boron Nitride/Graphene in a Thermoplastic Polyurethane Hybrid for Cooled Smart Clothes

“…Polymer nanocomposites with high thermal conductivity nanofillers have received increasing attention owing to their easy processing and low cost . Examples of such materials include composites with aluminum oxide (Al 2 O 3 ), graphene nanoplatelets (GNPs), − and boron nitride (BN) nanofillers. − However, the thermal conductivity of polymer composite materials can still be affected by factors such as the nanofiller loading, interface, geometry/aspect ratio, and dispersion state . In addition, the dispersion of the nanofillers in composite materials also affects the thermal conductivity because heat transfer usually occurs via the vibrational energy of atoms in solid materials.…”