Characterization methods for plasma process-induced damage to dielectric films with pre-existing defects

Abstract Interlayer dielectric (ILD) films contain various defect structures originating from species in precursor gases during deposition processes, as well as from plasma irradiation during manufacturing—known as plasma-induced damage (PID). This study investigates how pre-existing defects in ILD (SiO 2 ) films influence PID analysis. We examined changes in electrical characteristics by Ar and He plasma exposures using Al/SiO 2 /Si devices. Statistical current – voltage ( I–V ) analysis assigned significant distortion of the intrinsic I–V curves and an increase in the dielectric breakdown voltage of the SiO 2 films after plasma exposure, which may lead to erroneous PID assessments. Constant-voltage stress (CVS) tests were applied to address how the profiles of defects—created during deposition, plasma exposure (PID), and CVS—affect reliability lifetime predictions. The time evolutions of current under CVS were found to provide a precise and correct PID assessment.