Investigation of Ta, TaN and TaSiN barriers for copperinterconnects

摘要

The effects of Ta, TaN, and TaSiN barrier materials on Cu seedlayers and subsequent electroplating were investigated. Significantagglomeration of the Cu seed on damascene trench sidewalls was observedafter annealing of the seed deposited on Ta and TaN barriers. WithTaSiN, a relatively smooth and continuous Cu seed layer was observedboth before and after the anneal. XRD studies indicate that Cu-filleddamascene lines with TaSiN barriers have the least stress and thestrongest (111) texture as compared to Cu-filled lines with Ta and TaNbarriers