Reliability and gate conduction variability of HfO 2-based MOS devices: A combined nanoscale and device level study

Abstract

The electrical properties and reliability of MOS devices based on high-k dielectrics can be affected when the gate stack is subjected to an annealing process, which can lead to the polycrystallization of the high-k layer. In this work, a Conductive Atomic Force Microscope (C-AFM) has been used to study the nanoscale electrical conduction and reliability of amorphous and polycrystalline HfO 2 based gate stacks. The link between the nanoscale properties and the reliability and gate conduction variability of fully processed MOS devices has also been investigated.