The statistical analysis of substrate current to soft breakdown in ultra-thin gate oxide n-MOSFETs

In this work, the characteristics of the substrate current to soft breakdowns (SBDs) in n-MOSFETs were Studied under constant voltage stress (CVS). The jump of the substrate current can be regarded a soft breakdown (SBD) event. Both the time-to-breakdown (t(BD)) obtained from I-sub, jumps and the SBD substrate current increment (Delta Isub((SBD))) followed Weibull distribution. The Weibull,Slopes of t(BD) and Delta Isub(SBD) increased with increasing test temperature, but the temperature dependence of the characteristic Delta Isub((SBD)) (63% Delta Isub((SBD))) is different. On,the other hand, the relation between the I-sub and I-g (gate current,) after SBDs was studied. Both the forming process and jumps of I-sub under CVS were described and explained by the variable frequency light pumping effect (VFLP).Engineering, Electrical & ElectronicMaterials Science, MultidisciplinaryPhysics, Condensed MatterCPCI-S(ISTP)