Understanding DRAM Array Contact Missing: Mechanisms Study with Practical Solutions: YE: Yield Enhancement/Learnin

Gaining insight into the interaction of processing elements is crucial for maintaining stability in device and electrical performances, particularly in high-volume manufacturing environment. This paper unveils a challenge arising during the transition from a hard mask process to a new vendor, leading to a run-to-run shift in the downstream dry etch process and causing under-etching. The study addresses this issue through the optimization of run-to-run processes, ensuring better alignment of hard mask film characteristics, and enhancement in within-wafer uniformity. Additionally, the paper endeavors to unravel the underlying process elements contributing to the occurrence of missing contacts.