Constant field stressing of via-to-line spacing for accurate projection of intrinsic TDDB lifetime

We proposed solutions for determining the accurate projection of the TDDB lifetime of via-to-line spacing; that is, using a single-via test structure and constant field stress. This method eliminates the lifetime variations due to the spacing variations more effectively than conventional methods, for example, area scaling. The projected lifetime under the given use conditions increased at least about two-orders of magnitude by using this method, showing that constant field stress can be used to effectively project intrinsic TDDB lifetimes.