Structural and optical analysis of ZnBeMgO powder and thin films

Abstract: We here report the structural and optical studies of Zn1−x−y Be x Mg y O (0≤ x ≤0.15; 0≤ y ≤0.20) powders and thin films. From the Rietveld refinement of the powder X-ray diffraction (XRD) patterns it was revealed that the value of ‘a’ lattice parameter remains almost unchanged whereas ‘c’ parameter reduces with Be and Mg co-doping in ZnO. The Zn-O bond length also decreases in co-doped samples. Raman studies of the pure ZnO powder showed all the characteristic peaks of the wurtzite hexagonal structure and with (Be, Mg) co-doping new modes appeared which can be attributed to arise as a result of substitution. The XRD of the films prepared from the powders using pulsed laser deposition (PLD) technique exhibited the preferential orientation and with increase in co-doping the (0002) peak also shifts to higher 2θ values suggesting the incorporation of Be/Mg at the Zn-site. From the UV–visible optical transmittance measurement it was noticed that the band gap of the pristine ZnO film is 3.3eV which enhanced up to 4.51eV for Zn0.7Be0.1Mg0.2O film which lies in the solar blind region and is very useful in the realization of deep UV detectors. [ABSTRACT FROM AUTHOR]