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Journal of Applied Physics

Publication date: 2015-06-01
Volume: 117
Publisher: American Institute of Physics

Author:

Knebel, Steve
Pesic, Milan ; Cho, Kyuho ; Chang, Jaewan ; Lim, Hanjin ; Kolomiiets, Nadiia ; Afanas'ev, Valeri ; Muehle, Uwe ; Schroeder, Uwe ; Mikolajick, Thomas

Keywords:

Science & Technology, Physical Sciences, Physics, Applied, Physics, ACCELERATION MODEL, DIELECTRICS, 01 Mathematical Sciences, 02 Physical Sciences, 09 Engineering, Applied Physics, 40 Engineering, 49 Mathematical sciences, 51 Physical sciences

Abstract:

Aiming for improvement of the ZrO2-based insulator properties as compared to the state-of-the-art ZrO2/Al2O3/ZrO2 stacks beyond 20 nm dynamic random access memory (DRAM) technology applications, ultra-thin (5 nm) ZrO2/SrO/ZrO2 stacks with TiN electrodes deposited by physical vapor deposition are addressed. By replacing the Al2O3 interlayer with SrO, the effective dielectric permittivity of the stack can be increased as indicated by electrical analysis. At the same time, no degradation of the insulating properties of the SrO-containing stacks and minor changes in the reliability, compared to an Al2O3 interlayer, are found. These results are indicating the possibility of further reducing the effective oxide thickness of the ZrO2-based stacks to come close to 0.5 nm for future DRAM capacitors.