1 Band gaps of wurtzite Sc x Ga 1 - x N alloys
نویسندگان
چکیده
Optical transmittance measurements on epitaxial, phase-pure, wurtzite-structure ScxGa1-xN films with 0 ≤ x ≤ 0.26 showed that their direct optical band gaps increased from 3.33 eV to 3.89 eV with increasing x, in agreement with theory. These films contained I1and I2-type stacking faults. However, the direct optical band gaps decreased from 3.37 eV to 3.26 eV for ScxGa1-xN films which additionally contained nanoscale lamellar inclusions of the zincblende phase, as revealed by aberration-corrected scanning transmission electron microscopy. Therefore we conclude that the apparent reduction in ScxGa1-xN band gaps with increasing x is an artefact resulting from the presence of nanoscale zinc-blende inclusions.
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تاریخ انتشار 2015