Caracterisation d'une barriere de diffusion de TiN oxydee par plasma (French text, titanium nitride).

摘要

The determination of the phases formed in AlSiCu/TiN/Ti contact metallization multilayers of VLSI/ULSI circuits by X-ray diffraction is useful in order to study the effect of the annealing temperature, the oxidation treatment of the TiN, the barrier thickness and also the Si or SiO{dollar}sb2{dollar} substrate. The most striking results are the formation of the Ti{dollar}sb7{dollar}Al{dollar}sb5{dollar}Si{dollar}sb{lcub}12{rcub}{dollar} phase and the Al recrystallization to the (111) orientation after a 550{dollar}spcirc{dollar}C annealing for a non-oxidized 50 nm TiN on Si substrate. These changes tend to be blocked when an air-exposed barrier is used. We therefore suggest that the reduced formation of Ti{dollar}sb7{dollar}Al{dollar}sb5{dollar}Si{dollar}sb{lcub}12{rcub}{dollar} results in improved stability of the layers after TiN oxidation.; A 45s ex-situ oxygen plasma treatment of the TiN barrier was studied and it was determined that this process increases the formation of Al{dollar}sb2{dollar}O{dollar}sb3{dollar} and shows a lower TiAl{dollar}sb3{dollar} proportion than a process air break.; The main problem with the ex-situ oxygen plasma is that an air break is still needed and therefore does not improve the process throughput. On the other hand, a 35s in-situ Ar/O{dollar}sb2{dollar} plasma developped by Mitel S.C.C. could be performed in the cluster tool prior to the Al alloy deposition. (Abstract shortened by UMI.)