Conductance transient comparative analysis of electron-cyclotron resonance plasma-enhanced chemical vapor deposited SiNx, SiO2/SiNx, and SiOxNy dielectric films on silicon substrates

An interface quality comparative study of metal-insulator-semiconductor (MIS) structures based on SiNx, SiO2/SiNx and SiO(x)Ny dielectric films deposited on silicon substrates by electron-cyclotron resonance plasma-enhanced chemical vapor deposition (ECR-PECVD) has been carried out. Overall interpretation of deep-level transient spectroscopy (DLTS) and conductance transient (G-t) measurements enables us to conclude that the interface quality of Al/SiOxNy/Si MIS structures is superior to those of Al/SiNx/Si devices. Moreover,. we have proved that thermal treatments applied to Al/SiOxNy/Si capacitors induce defect passivation, possibly related to the presence of hydrogen in the films, and disorder-induced gap-state (DIGS) density maxima can decrease to values even lower than those corresponding to Al/SiNx/SiO2/Si devices