Low Voltage Stress Induced Substrate Current as a Monitor for Interface States generation in ultra-thin oxide n-MOSFETs

In this paper, the low voltage stress induced substrate leakage current (I_b) was studied based on generation kinetics and using it as a monitor of interface states (N_it) generation for ultra-thin oxide MOSFETs after periodical stress interruptions. It is found the low voltage I_b is formed by electrons tunnel through interface states, and its variations DeltaI_b are proportion to N_it variations (DeltaN_it). The N _it energy distributions were determined by substrate leakage current variations. The obtained results were compared with that measured by gate diode techniques