Zinc magnesium oxide is a ternary compound wide bandgap semiconductor. Incorporation of Mg into ZnO helps in increasing the of p-type conductivity by affecting the background n-type nature of ZnO. This is possible because Mg incorporation in ZnO elevates the conduction band edge which in turn increases the distance between the shallow donor level and conduction band minima, resulting increase of activation energy for background donor. In this work, we report Spin-on Dopant technique to dope phosphorus in Zn0.85Mg0.15O lattice. The undoped ZnMgO thin film (sample A) was deposited using RF sputtering. The SOD sample (sample B) was prepared using P509 spin on dopant and kept approximate 1cm above ZnMgO film at 600°C for four hours. The doped sample was annealed at temperature 700°C (sample C) in oxygen ambient to see the high temperature annealing effect on doping. In studies of high-resolution x-ray diffraction, a dominant (002) peak was observed in sample A, B, and C at 34.173°, 34.624°, and 34.638° respectively. The shifting of (002) peak at higher angle for doped samples indicates the phosphorus doping in film. The XPS spectra of phosphorus 2p peak are appears at ~134 eV indicates the presence of P atoms as P-O bonds in ZnMgO lattice. The Donor-Acceptor pair (DAP) transition peak around 3.473eV and free Acceptor (AX°) peak around 3.588eV were found in photoluminescence spectra of sample B revels the phosphorus doping in ZnMgO.
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