Sven Schmidbauer

Advanced Hi-Fill® for interconnect liner applications

Ti/TiN liner and barrier deposition for low contact resistance tungsten plug interconnect metallisation schemes represent a major challenge for current and future aspect ratios of interconnect vias. For Ti, bottom coverage is important to minimise contact and via resistance and for TiN, good sidewall coverage is required to maintain the integrity of the W fill process. This paper describes the fundamental operation and characterisation of a novel ionised dual metal/metal nitride deposition chamber--Advanced Hi-Fill®. Discussed is the incorporation of Advanced Hi-Fill® technology into a BEOL production environment. Production data for via level interconnects manufactured in a 0.17-µm logic product as well as contact level for a 0.14-µm DRAM product is presented.

Extendibility of ultra throw Ti-barriers passivated in nitrogen

Abstract This study involves evaluation of a Ti liner deposited by long throw (i.e. Hi-fill ® and ULTRA) and comparison of different cooling regimes using Ar and N 2 as atmosphere in the case of ULTRA. The use of N 2 -based cooling led to a surface passivation against oxidation. Therefore the effective Ti-thickness could be reduced by a factor of 1.5. Surface analysis and electrical results are discussed within the paper.

Novel metallization scheme using nitrogen passivated Ti liner for AlCu-based metallization

In many fabs for quarter micron and below technologies a stack consisting of Ti/TiN/AlCu/TiN or Ti/AlCu/TiN is being used for metallization. A new approach for metal stack deposition of 0.25 micrometers and beyond, utilizing hew design rules, has been used for DRAM processes. The novel metal deposition process uses an insitu nitrogen purge directly after deposition of bottom Ti to achieve a passivation of the Ti with a thin nitride before deposition of AlCu. This novel approach has been compared to standard metallization stacks consisting of Ti/AlCu/TiN and Ti/TiN/AlCu/TiN.