Temperature-dependent Raman property of n-type SiC

Abstract

Micro-Raman scattering from the nitrogen doped n-SiC is performed at the temperatures ranging from 100 to 450 K. The temperature dependences of the first-order Raman scattering, electronic Raman spectra and the second-order Raman features are obtained. These measurements reveal that most of the first-order Raman phonon frequencies decrease with temperature increasing, but the redshifts of the acoustic phonon modes are smaller than those of the optical phonon modes. Meanwhile, the longitudinal optical phonon-plasma coupled (LOPC) mode manifests different features with temperature increasing. The LOPC mode tends to have a blueshift at a lower temperature but a redshift at a higher temperature. This indicates that the temperature dependence of LOPC mode is affected not only by the anharmonic effects, but also by the ionized donor concentration. With the increase of the measurement temperature, the intensity of the electronic Raman spectrum decreases, and the linewidth gradually broadens, but the electronic Raman signal is almost not shifted. The redshift of the second-order Raman spectrum is smaller than that of the first-order Raman spectrum, but the intensity of the second-order Raman spectrum substantially decreases with the increase of temperature.

Temperature-dependent characteristics of 4H—SiC junction barrier Schottky diodes

“…Equation (3) shows that in a suitable range of forward bias voltage, the slope of the forward waveform in logarithmic coordinates should be close to q/kT , therefore, n should have a value close to 1.…”

Growth and Temperature-Depending Raman Characterization of Different Nitrogen-Doped 4H-SiC Crystals

“…Raman scattering was used to probe the vibrational states of SiC, which are also very sensitive to temperature [5]. In general, temperature dependent Raman scattering measurements are well suited to better understand the electronic properties of semiconductors at different temperatures as well as to analyze more specific aspects of lattice dynamics [6].…”