Conductance Transient Comparative Analysis of Electron-Cyclotron Resonance Plasma-Enhanced Chemical Vapor Deposited SiN_x, SiO_2/SiN_x and SiO_xN_y Dielectric Films on Silicon Substrates

摘要

An interface quality comparative study of metal-insulator-semiconductor (MIS) structures based on SiN_x, SiO_2/SiN_x and SiO_xN_y 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/SiO_xN_y/Si MIS structures is superior to those of Al/SiN_x/Si devices. Moreover, we have proved that thermal treatments applied to Al/SiO_xN_y/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/SiN_x/SiO_2/Si devices.