Optical characterization of metalorganic vapor-phase epitaxy-grown GaAs_1-xN_x alloys using spectroscopic ellipsometry

摘要

We have measured complex dielectric functions, ε_1+iε_2, of GaAs_1-xN_x alloys using spectroscopic ellipsometry to investigate higher-energy band gaps. The E_1 gap-related peak height for ε_2 decreases with increasing N concentration, indicating that the optical absorption at the E_1 gap decreases. On the contrary, the E_2 gap transition does not change so much with varying N concentration.