Very Deep M1 contact process integration on W bit line depending on the different premetal cleanings and barrier metals Ti/TiN

摘要

M1 contact resistance on w bit line is evaluated with PVD and CVD barrier metal TiN for pre metal cleanings of the BOE wet and RF dry up to contact aspect ratio of 17. Optimum contact chain resistance and uniformity can be obtained with RF dry cleaning and IMP Ti/TiN barrier metal. It is point out that CVD W studding in contact hole depends on contact profile and barrier metal, and minimizing key hole will be primary for lowing contact resistance for the very deep metal contact.