The Effect of Degradation of Gate Oxide on the Electrical Parameters for Sub-Micron MOSFETS

박막 게이트 산화막의 열화에 의해 나타나는 MOSFET의 특성 변화

Experimental results are presented for gate oxide degradation and its effect on device parameters under negative and positive bias stress conditions using NMOSFET's with 3 nm gate oxide. The degradation mechanisms are highly dependent on stress conditions. For negative gate voltage, both hole- and electron-trapping are found to dominate the reliability of gate oxide. However, with changing gate voltage polarity, the degradation becomes dominated by electron trapping. Statistical parameter variations as well as the "OFF" leakage current depend on those charge trapping. Our results therefore show that Si or O bond breakage by electron can be another origin of the investigated gate oxide degradation.gradation.