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Title: A Reliability Study of Thickness Dependence of HfO2-based 3D-FeRAM Cell
Thickness-dependent reliability in 3D-Cap HfO2-based FeRAM capacitors has been studied. Results show endurance larger than 1011 cycles and >10 years of extrapolated retention time. A significant polarization gain was made possible due to trenched capacitors that enhanced the effective areas. A major cause of the endurance failure is the dielectric breakdown after numerous cycles, which is linked to the gate leakage currents. Our temperature-dependent study of I-V characteristics has revealed Fowler-Nordheim tunneling at low temperatures and Frenkel-Poole conduction at room-to-high temperatures as the culprits. Such findings will be helpful for future commercialization of this technology.
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IEEE Semiconductor Interface Specialist Conference
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National Science Foundation
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