Negative-bias-temperature-instability in metal–insulator–semiconductor structures

Abstract

We have demonstrated that negative-bias-temperature-instability (NBTI) significantly decreases the minority carrier generation lifetime as well as modifying the dominant source supplying minority carriers to the inversion layer at the semiconductor–insulator interface. This was manifested by an NBTI-induced shift in the deep-level-transient-spectroscopy (DLTS) peak signal associated with the inversion layer formation at the semiconductor–insulator interface at temperatures above room temperature to a lower temperature. In addition, we have observed that the DLTS inversion layer-related peak signal gradually shifted back, close to its pre-NBTI temperature position after a substantial time at zero bias-voltage and room temperature conditions had elapsed since the NBTI experiment. We have tentatively ascribed this recovery to a post-NBTI reaction at the semiconductor–insulator interface between unpassivated positively charged silicon dangling bonds and negatively charged hydrogen ions.