Electron effective masses and mobilities in high-purity 6H–SiC chemical vapor deposition layers

The first observation of cyclotron resonance in 6H-SiC by optically detected cyclotron resonance (ODCR) spectroscopy at X-band microwave frequency is reported. High purity undoped, n-type 6H-SiC layers grown by chemical vapor deposition (CVD), with residual doping concentrations in the 1014–1015 cm−3 range, were investigated. Effective mass values were determined as m*⊥=(0.42±0.02)m0 and m*∥=(2.0±0.2)m0. From the fit of the ODCR line shape, a remarkably high mobility at 6 K was deduced: μ⊥≊1.1×105 cm2/V s for electrons in the basal plane. The anisotropy of the effective mass and the carrier mobility is discussed in comparison with previously reported data.