Novel, Effective and Cost-Efficient Method of Introducing Fluorine into Metal/Hf-based Gate Stack in MuGFET and Planar SOI Devices with Significant BTI Improvement

In this work, we propose a new, effective, and cost-efficient method of introducing fluorine into metal/Hf-based gate stack of planar and multi-gate devices (MuGFET), resulting in significant improvements in both NBTI and PBTI characteristics. The key advantage of this method is that it uses the SF₆-based metal gate etch for F introduction, requiring no extra implantation steps. In addition to the significant BTI improvement with the novel method, we also demonstrate, for the first time, better V_th control and increased drive current on MuGFET devices.