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.
Low leakage stoichiometric SrTiO3 dielectric for advanced metal-insulator-metal capacitors / Popovici, Mihaela; Kaczer, Ben; Afanas'Ev, Valeri V.; Sereni, Gabriele; Larcher, Luca; Redolfi, Augusto; Van Elshocht, Sven; Jurczak, Malgorzata. - In: PHYSICA STATUS SOLIDI. RAPID RESEARCH LETTERS. - ISSN 1862-6254. - 10:5(2016), pp. 420-425. [10.1002/pssr.201600036]