High-mobility Sb-doped p -type ZnO by molecular-beam epitaxy

Reproducible Sb-doped p -type ZnO films were grown on n - Si (100) by electron-cyclotron-resonance-assisted molecular-beam epitaxy. The existence of Sb in ZnO:Sb films was confirmed by low-temperature photoluminescence measurements. An acceptor-bound exciton ( A ° X ) emission was observed at 3.358 eV at 8 K. The acceptor energy level of the Sb dopant is estimated to be 0.2 eV above the valence band. Temperature-dependent Hall measurements were performed on Sb-doped ZnO films. At room temperature, one Sb-doped ZnO sample exhibited a low resistivity of 0.2 Ω cm , high hole concentration of 1.7 × 10 18 cm − 3 and high mobility of 20.0 cm 2 ∕ V s . This study suggests that Sb is an excellent dopant for reliable and reproducible p -type ZnO fabrication.