The Effect of the Subthreshold Slope Degradation on NBTI Device Characterization

A new fast switching NBTI measurement method was introduced based on applying alternating V_GS test conditions to determine SS-NBTI results using this new method show that unexpectedly SS decreases (improves) with stress time ?? It was determined that SS improves during NBTI Stress because device |VT| increases effectively moving the VGS @ test point to a reduced |ID| point ?? An improvement in the pending NBTI JEDEC test standard was proposed which consists of incrementing the test VGS after each stress interval effectively keeping the test point at ID(0) - NBTI results from this improved method were in qualitative agreement with post stress ID-VGS results