Electron effective masses in 4H SiC

Results from optically detected cyclotron resonance (ODCR) studies of electron effective masses in 4H SiC are reported. ODCR measurements were performed on high-purity n-type 4H SiC epitaxial layers grown by chemical vapor deposition at both X band (9.23 GHz) and Q band (35.05 GHz) microwave frequencies. Electron effective masses in 4H SiC were directly determined as m⊥*=0.42m0 and m∥*=0.29m0. A scattering time in the basal plane τ⊥≊4.3×10−11 s, and hence, the corresponding electron mobility μ⊥≊1.8×105 cm2/V s, was obtained from a fit of the ODCR line shape.