The Systematic Investigation about Al diffusion and Efficient Improvement on Device Variation and Uniformity Under 28nm HKMG Process

In 28HKMG node, the Al diffusion is considered as the major factor that will influence the threshold voltage and device uniformity. In this paper, we systematically investigate the mechanism of Al diffusion and develop two methods to improve the Al diffusion. By reducing the Al diffusion effect, the local and global variation and device mismatch is remarkably improved and the large process/device window and yield improvement can be acquired.