Low leakage stoichiometric SrTiO3 dielectric for advanced metal–insulator–metal capacitors. Issue 5 (23rd March 2016)

• Record Type: Journal Article
• Authors: Popovici, Mihaela; Kaczer, Ben; Afanas'ev, Valeri V.; Sereni, Gabriele; Larcher, Luca; Redolfi, Augusto; Elshocht, Sven Van; Jurczak, Malgorzata
• Is Part Of: Physica status solidi. Volume 10:Issue 5(2016)
• Page Start: 420
• Page End: 425
• Publication Date: 2016-03-23
• Subjects: capacitors -- SrTiO3 -- atomic layer deposition -- leakage current -- stoichiometric dielectric; Solid state physics -- Periodicals; 530.4105
• DOI: 10.1002/pssr.201600036
• Languages: English
• ISSNs: 1862-6254

Abstract

Abstract : Metal–insulator–metal capacitors (MIMCAP) with stoichiometric SrTiO3 dielectric were deposited stacking two strontium titanate (STO) layers, followed by intermixing the grain determining Sr‐rich STO seed layer, with the Ti‐rich STO top layer. The resulted stoichiometric SrTiO3 would have a structure with less defects as demonstrated by internal photoemission experiments. Consequently, the leakage current density is lower compared to Sr‐rich STO which allow further equivalent oxide thickness downscaling.Schematic of MIMCAP with stoichiometric STO dielectric formed from bottom Sr‐rich STO and top Ti‐rich STO after intermixing during crystallization anneal. (© 2016 WILEY‐VCH Verlag GmbH &Co. KGaA, Weinheim) Abstract : Formation of thin films of stoichiometric strontium titanate with uniformly distributed grains at nanometer scale was demonstrated. If the trap‐assisted conduction is suppressed, SrTiO3 films would have the potential to be used as dielectric in metal–insulator–metal capacitors for the sub‐20 nm DRAM technology node.