Dielectric, resistivity, and current–voltage characteristics of magnesium-doped tin oxide for optoelectronics application

For years, scientists have been working to identify new oxide materials with appropriate properties that could be used in the development of next–generation optoelectronic and spintronic devices. We investigated the electrical characteristics (Dielectric, Current–Voltage, and Resistivity) of Sn_1-xMg_xO₂ compounds (0 ≤ x ≤ 0.10) to assess their suitability for optoelectronic device applications. The SEM microstructural analysis of the sample showed that it was homogeneous, with an average grain size of around 60–70 nm. The elemental distribution, as revealed by EDS mapping, was agglomerated into various crystals. In order to understand the frequency-dependent dielectric behavior of Mg-doped SnO₂ compounds, the Maxwell–Wagner model was employed to examine the dielectric constant (ε_r), loss tangent (tan δ), complex impedance, and ac conductivity. The current–voltage (I–V) characteristics of the sample were examined using a Keithley 6517b electrometer in two–probe mode with a Tin metal pressure contact. The results showed that the I–V curve exhibited an Ohmic behavior, indicating a linear relationship between current and voltage. Furthermore, the room-temperature resistivity study revealed that the material is highly resistive in nature.