Bias-dependent photo-detection of dual-ion beam sputtered MgZnO thin films

[摘要] The structural, morphological, elemental and electrical properties of MgZnO thin films, grown on p-Si (001) substrates by dual-ion beam sputtering deposition (DIBSD) system at different substrate temperatures were thoroughly investigated. X-ray diffraction (XRD) pattern of MgZnO film exhibited crystalline hexagonal wurtzite structure with the preferred (002) crystal orientation. The full-width at half-maximum of the (002) plane was the narrowest with a value of 0.226° from MgZnO film grown at 400°C. X-ray photoelectron spectroscopy analysis confirmed the substitution of Zn$^{2+}$ by Mg$^{2+}$ in MgZnO thin films and the absence of MgO phase. Correlation between calculated crystallite size, as evaluated from XRD measurements, and room-temperature carrier mobility, as obtained from Hall measurements, was established. Current–voltage characteristics of MgZnO thin films were carried out under the influence of dark and light illumination conditions and corresponding values of photosensitivity were calculated. MgZnO film grown at 100°C exhibited the highest photosensitivity of 1.62. Compared with one of the best-reported values of photosensitivity factor from ZnO-material-based films available in the literature, briefly, $\sim$3.085-fold improved photosensitivity factor at the same bias voltage (2 V) was obtained.

[学科分类] 材料工程

[关键词] DIBSD;growth temperature;Hall measurements;MgZnO thin films;XRD;XPS.