Far-infrared absorption, cyclotron resonance and electron paramagnetic resonance measurements of silicon carbide

摘要

We have studied electronic and phonon properties in hexagonal-type (4H, 6H) SiC through far-infrared (FIR) absorption, cyclotron resonance (CR) and electron paramagnetic resonance (EPR) measurements. For the FIR absorption in 6H-SiC samples, a narrow doublet and a singlet lines located at 240 and 235 cm~(-1) are observed, respectively. It is found that the temperature variation of these lines is closely related to concentration of impurities. For the CR, an effective mass of the conduction band and temperature dependence of relaxation time in 4H-SiC are estimated. For the EPR, three lines due to N impurities with hyperfine structure are observed. It is found that behavior of temperature dependence of the EPR signals is similar to that of the vibrational mode.