Laser Anneal-Induced Effects on the NBTI Degradation of Advanced-Process 45nm High-K PMOS

Abstract

This paper presents the effects imposed on the reliability of advanced-process CMOS devices, specifically the NBTI degradation, subsequent to the integration of laser annealing (LA) in the process flow of a 45nm HfO2/TiN gate stack PMOS device. The laser annealing temperatures were varied from 900°C to 1350°C. The effects imposed on the NBTI degradation of the device were comprehensively analyzed in which the shifts of the threshold voltage and drain current degradation were observed. The analysis was extended to the effects of the conventional RTA as opposed to the advanced laser annealing process. It was observed that the incorporation of laser annealing in the process flow of the device enhances the NBTI degradation rate of the device, in contrast to the integration of the conventional RTA. Laser annealing subsequent to spike-anneal is observed to improve the reliability performance of the transistor at high negative biases.