Bandgap engineering of Ga x Zn 1 –x O nanowire arrays for wavelength‐tunable light‐emitting diodes

Wavelength‐tunable light‐emitting diodes (LEDs) of Ga x Zn 1–x O nanowire arrays are demonstrated by a simple modified chemical vapor deposition heteroepitaxial growth on p‐GaN substrate. As a gallium atom has similar electronegativity and ion radius to a zinc atom, high‐level Ga‐doped Ga x Zn 1–x O nanowire arrays have been fabricated. As the x value gradually increases from 0 to 0.66, the near‐band‐edge emission peak of Ga x Zn 1–x O nanowires shows a significant shift from 378 nm (3.28 eV) to 418 nm (2.96 eV) in room‐temperature photoluminescence (PL) measurement. Importantly, the electroluminescence (EL) emission of Ga x Zn 1–x O nanowire arrays LED continuously shifts with a wider range (∼100 nm), from the ultraviolet (382 nm) to the visible (480 nm) spectral region. The presented work demonstrates the possibility of bandgap engineering of low‐dimensional ZnO nanowires by gallium doping and the potential application for wavelength‐tunable LEDs.