Silver oxide (A2O) films were deposited on glass and silicon substrates held at temperatures in the range 303–473？K by reactive RF magnetron sputtering of silver target. The films formed at room temperature were single phase Ag2O with polycrystalline in nature, while those deposited at 373？K were improved in the crystallinity. The films deposited at 423？K were mixed phase of Ag2O and Ag. Atomic force micrographs of the films formed at room temperature were of spherical shape grains with size of 85？nm, whereas those deposited at 473？K were with enhanced grain size of 215？nm with pyramidal shape. Electrical resistivity of the single phase films formed at room temperature was 5.2 × 10？3？Ωcm and that of mixed phase was 4.2 × 10？4？Ωcm. Optical band gap of single phase films increased from 2.05 to 2.13？eV with the increase of substrate temperature from 303 to 373？K, while in mixed phase films it was 1.92？eV. 1. Introduction Silver-oxygen system (Ag-O) was extensively attracted by researchers due to its novel applications in high density optical storage devices, gas sensors, photovoltaic cells, photo diodes, and antibacterial coatings [1–6]. This system exists in different defined compounds, namely, Ag2O, AgO, Ag3O4, Ag4O3, Ag2O3, and Ag4O4. Among these oxides, Ag2O is the most thermodynamically stable. The compound Ag2O possesses a simple cubic structure at room temperature [7]. Ag2O in thin film form is a p-type semiconductor with a band gap ranging from 1.2 to 3.4？eV due to the deviation in the stoichiometry, structure and crystallinity, phases, and physical properties arising from the employed deposition technique [8]. Thermal decomposition of silver oxide into oxygen and silver is the unique characteristics which led to the promising technological applications. Kim et al. [9] reported that silver oxide films also act as a mask layer in magneto-optical disk to enhance the magneto-optical signal. However, the high threshold of thermal decomposition temperature >673？K for silver oxide films has been a bottleneck of application in optical and magneto-optical storage [10, 11]. The Ag2O films grown with (111) orientation by rapid thermal annealing process at temperature of 473？K find application as readout layer in a magneto-optical disk. Peyser et al. [12] achieved strong photoactivated emission of nanoscale Ag2O for excitation with a wavelength <520？nm find application in blue optical lasers. Nanoparticles of Ag2O embedded in ZnO inhibit the degradation in the performance of photodetector when annealed in oxygen ambient at temperature of 473？K [3]. Büchel et
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