Mg-doped ZnO thin film based capacitive memory with low leakage current

The study demonstrates the capacitive memory of ZnO TF and Mg-doped ZnO TF metal oxide semiconductor (MOS) capacitor synthesised on p-Si substrate using RF magnetron sputtering technique. The Field Emission Scanning Electron Microscope (FE-SEM) image shows the uniform growth of thin film (TF) with length of ⁓ 300 nm. Doping of Mg in ZnO the absorption band edge is shifted and an increment in bandgap were observed may be due to the formation of crystallographic defects and active adsorption sites, which can also be confirm from photoluminescence (PL) analysis. A low leakage current (4.22 × 10^–9 A), larger memory window (1.8 V), higher charge storage capability, and good endurance over 1000 programming/erasing cycles were recorded for Mg-doped ZnO TF device due to rise in deep level traps and better interface quality. Moreover, the interface state density (D_it) was computed and found to be 2.0 × 10¹⁰ eV⁻¹ cm⁻² at 1 MHz. As a result, the performance of Mg-doped ZnO TF could be a potential candidate for capacitive memory application.