Progressive-degradation and breakdown of W-La2O3 MOS structures after constant voltage stress

In this paper, we report the progressive electrical degradation and consequent breakdown (both soft and hard-breakdown regimes) of thin W-La₂O₃ stacked films deposited on silicon substrates and their influence on the electrical characteristics of metal-oxide-semiconductor (MOS) devices. Initial electrical degradation of the MOS devices results in an increase of the gate oxide leakage current (mostly known as Stress-Induced Leakage-Current, SILC), with the device´s practical effect being a monotonous shift in threshold voltage (?Vth) after constant voltage stressing. Following the initial degradation of the gate oxide, both soft and hard-breakdown modes are detected and their influence on the electrical characteristics of the MOS devices are also obtained and compared.