Characterizing SiC-AlN semiconductor solid solutions with indirect and direct bandgaps

摘要

The objective of the study is to characterize the dependence of the optical properties of solid solutions of silicon carbide and aluminum nitride on composition. Even small differences in composition provide manipulation of band gap features over a wide range. Data for this paper were collected by X-ray diffraction, photoluminescence and absorption spectroscopy. The evolution of the observed optical properties as a result of compositional changes were studied. X-ray studies confirm the presence of a(SiC)_(1-x)(AlN)_x solid solution. Investigation of absorption spectra shows the optical band gap of the sample with composition (SiC)_0.88(AlN)_0.12 is 3.5eV, and 4.24 eV for the (SiC)_0.36(AlN)_0.64 solid solution. The photoluminescence spectra demonstrate the strong dependence of the spectra on composition x. The experimental results are in agreement with theory. These data demonstrate the optimization of optical properties for particular optoelectronic applications by varying the (SiC)_(1-x)(AlN)_x composition.