Observing the Degradation and Breakdown Characteristics of Thin Gate Dielectrics Observed by Conductive Atomic Force Microscopy

Degradation and breakdown are the major reliability concerns of gate dielectric in modern metal-oxide-semiconductor (MOS) devices. Due to the highly localized nature of dielectric breakdown, scanning probe microscopy (SPM) based tools are very suitable for monitoring the degradation and breakdown of gate dielectric. In this paper the authors demonstrate the typical I-V characteristics as well as the dielectric breakdown behavior of gate dielectric subjected to electrical stresses measured by the conductive atomic force microscopy (C-AFM). The measurement capability of the C-AFM has been extended by connecting it with the Agilent 4156C semiconductor parameter analyzer. The effect of current compliance on C-AFM measured post-breakdown I-V characteristics is also discussed