Hot-electron characteristics in chemically resolved electrical measurements of thin silica and SiON layers

摘要

We use the recently developed chemically resolved electrical measurements (CREM) to sensitively measure hot-electron transport characteristics in thin dielectric layers. By comparing bare gate-oxide layers, SiO_2 and SiON, pronounced differences are revealed that are absent from standard contact measurements and from CREM conducted on top metallic pads. The "on pad" and standard measurements obey a similar defect-assisted "Poole-Frenkel" transport, whereas I～V~α characterizes the hot-electron transport through the bare overlayer, with a clear thickness dependence of α. These unique CREM features offer useful advantages in gate-oxide characterization.