Cathodoluminescence Studies of the Inhomogeneities in Sn-doped Ga2O3 Nanowires

Cathodoluminescence real-color imaging and spectroscopy were employed to study the properties of Ga2O3 nanowires grown with different Sn/Ga ratios. The structures grown under Sn-rich conditions show large spectral emission variation, ranging from blue to red, with a green transition zone. Spectral emission changes correlate with changes in the chemical composition and structure found by energy dispersive spectroscopy and electron diffraction. A sharp transition from green to red emission correlates with a phase transition of beta-Ga2O3 to polycrystalline SnO2. The origin of the green emission band is discussed based on ab initio calculation results.