2 research outputs found
Poole-Frenkel conduction in Al/ZrO
Leakage currents through Al/ZrO2/SiO2/n-Si metal-insulator-semiconductor (MIS) capacitors were studied. Thin SiO2 films were chemically grown on monocrystalline phosphorous doped silicon wafers. Zirconia films with thicknesses of 15 and 50Â nm were
deposited by radio frequency (rf) magnetron sputtering and, then,
annealed in oxygen ambient at 850Â â—‹C, for 1Â h. The dielectric constant
of the sputtered and annealed ZrO2 layer was of about 17.8. The
equivalent oxide thickness (EOT) of the stack 15Â nm and 50Â nm-ZrO2/SiO2 structure was estimated to be 3.2Â nm and 10.7Â nm, respectively. The temperature dependence of the leakage currents was explained by Poole-Frenkel (PF) conduction mechanism. Shallow trap levels in the studied structure of about 0.2Â eV and 0.46Â eV were calculated. The existence of A and D-defects, due to the sputtering and high temperature annealing in oxygen, was suggested