Enhanced Reliability of 7-nm Process Technology Featuring EUV

Abstract

In this article, we report the reliability characterization of 7-nm technology, in which the highly scaled sixth generation of FinFETs and 256-Mb static random access memory (SRAM) cells were newly developed by featuring extreme ultraviolet (EUV). The intrinsic reliability mechanisms of 7-nm FinFET including hot carrier injection (HCI), bias temperature instability (BTI), and time-dependent dielectric-breakdown (TDDB) are similar to that of the previous nodes, and would not be degraded by introducing the scaled FinFET. Moreover, we found that the use of EUV single patterning of middle of line (MOL) and back end of line (BEOL) improves reliability distribution remarkably as compared to the previous nodes using argon fluoride (ArF) multiple patterning techniques. We successfully demonstrated SRAM and logic high-temperature operating life (HTOL) up to 500 h, indicating the robustness of product-level reliability. These findings strongly suggest that the 7-nm technology featuring EUV is fully ready for high-volume manufacturing as well as providing a near future logic production with high-quality reliability.