Publication detail

Spin dynamics of exchange-coupled nitrogen donors in heavily doped n-type 15R SiC monocrystals: Multifrequency EPR and EDMR study

SOLODOVNYK, A. LAGUTA, O. PROKHOROV, A. SEGANTINI, M. NAYDENOV, B. NEUGEBAUER, P. GREULICH-WEBER, E. KALABUKHOVA, E. SAVCHENKO D.

Original Title

Spin dynamics of exchange-coupled nitrogen donors in heavily doped n-type 15R SiC monocrystals: Multifrequency EPR and EDMR study

Type

journal article in Web of Science

Language

English

Original Abstract

Semiconductor devices based on 15R silicon carbide (SiC) show improved properties compared to other polytypes. Here, we report the investigation of nitrogen-doped 15R SiC monocrystals with (ND–NA ) ∼ 5×1018 cm−3 using multifrequency electron paramagnetic resonance (EPR) and electrically detected magnetic resonance (EDMR) spectroscopic methods in the microwave (MW) frequency range from 9.4 to 328.84 GHz and in the temperature range from 4.2 to 300 K. A single intensive S line with S = 1/2, at g⊥ = 2.0026(2), and g = 2.0043(2) dominates the EPR spectrum in 15R SiC at T < 160 K and was attributed to the exchange-coupled nitrogen (N) donors substituting quasicubic “k1” site having the deeper energy level in 15R SiC lattice. From the analysis of the temperature behavior of the integral intensity, magnetic field position, intensity, shape, and width of the S line, it was concluded that at T < 90 K, the exchange coupling occurs between localized donor electrons, while at T = 90−150 K the interaction between exchange-coupled N donors and conduction electrons takes place. In the temperature interval from 20 to 160 K, the S-line EPR width was characterized by a two-phonon Orbach relaxation process with the activation energy of ∼6.5 meV corresponding to the valley-orbit splitting values for N donors in 15R SiC. The variable-range hopping regime obeying the T 1/4 law was found to take place at T < 20 K leading to the appearance of the S line in the EDMR spectrum at low temperatures. The appearance of the EDMR signal from exchange-coupled N donors is caused by the EPR-induced temperature-increase mechanism and the spin-flip hops process. The results obtained from MW conductivity measurements agree with EPR and EDMR data. The temperature variation of MW conductivity was described by several processes, including the electron-hopping process between N donor impurity atoms at T < 50 K with activation energy ε3 = 1.5 meV, electron transitions between Hubbard bands at T = 50–100 K; the transition of the electrons from the donor energy levels to conduction band with ionization energy ε1 = 32 meV at T = 100–200 K and scattering of theconduction electrons by ionized donors occurred at the temperature higher than 200 K

Keywords

ELECTRON-PARAMAGNETIC-RESONANCE; CAVITY PERTURBATION TECHNIQUE; SILICON-CARBIDE; MICROWAVE CONDUCTIVITY; MAGNETIC-RESONANCE; RESISTIVITY; ABSORPTION; CENTERS; METALS; GROWTH

Authors

SOLODOVNYK, A.; LAGUTA, O.; PROKHOROV, A.; SEGANTINI, M.; NAYDENOV, B.; NEUGEBAUER, P.; GREULICH-WEBER, E.; KALABUKHOVA, E.; SAVCHENKO D.

Released

13. 4. 2023

Publisher

American Physical Society

ISBN

2469-9969

Periodical

PHYSICAL REVIEW B

Year of study

107

Number

155202

State

United States of America

Pages count

13

URL

https://journals.aps.org/prb/abstract/10.1103/PhysRevB.107.155202

BibTex

@article{BUT183292,
  author="SOLODOVNYK, A. and LAGUTA, O. and PROKHOROV, A. and SEGANTINI, M. and NAYDENOV, B. and NEUGEBAUER, P. and GREULICH-WEBER, E. and KALABUKHOVA, E. and SAVCHENKO D.",
  title="Spin dynamics of exchange-coupled nitrogen donors in heavily doped n-type 15R SiC monocrystals: Multifrequency EPR and EDMR study",
  journal="PHYSICAL REVIEW B",
  year="2023",
  volume="107",
  number="155202",
  pages="13",
  doi="10.1103/PhysRevB.107.155202",
  issn="2469-9969",
  url="https://journals.aps.org/prb/abstract/10.1103/PhysRevB.107.155202"
}