On the electrical characterization of high-κ dielectrics

The continual scaling of complementary metal oxide semiconductor (CMOS) technologies has pushed the Si-SiO2 system to its very limits and has led to the consideration of a number of alternative high-kappa gate dielectric materials. In the end. it will be the electrical properties of the new Si/high-kappa system that will determine its usefulness in future CMOS generations. For this reason, the study of the electrical properties of high-kappa gate insulators is crucial. We present an overview of some of the electrical characterization techniques and reliability tests used to evaluate possible high-kappa gate materials. Most of these techniques are well known from the characterization of SiO2 layers, but there are some additional complications, such as the presence of several different layers within one gate stack or the use of different gate electrode materials. These make the interpretation and comparison of experimental results more troublesome.