Embedded ferroelectric memory technology with completely encapsulated hydrogen barrier structure

• Published in: IEEE transactions on semiconductor manufacturing Vol. 18; no. 1; pp. 49 - 54
• Main Authors: Nagano, Y., Mikawa, T., Kutsunai, T., Natsume, S., Tatsunari, T., Ito, T., Noma, A., Nasu, T., Hayashi, S., Hirano, H., Gohou, Y., Judai, Y., Fujii, E.
• Format: Journal Article
• Language: English
• Published: New York IEEE 01.02.2005; The Institute of Electrical and Electronics Engineers, Inc. (IEEE)
• Subjects: Capacitors; Ferroelectric films; Ferroelectric materials; Ferroelectric memory; Hydrogen; hydrogen barrier; Large scale integration; Low voltage; low-voltage operation; Nonvolatile memory; Random access memory; reliability; Transistors; Tungsten
• ISSN: 0894-6507; 1558-2345
• DOI: 10.1109/TSM.2004.841821

A 0.18-/spl mu/m system LSI embedded ferroelectric memory (FeRAM) operating at a very low voltage has been developed for the first time. The low-voltage operation has been attained by newly developed stacked ferroelectric capacitors completely encapsulated by hydrogen barriers, which enable us to eliminate hydrogen reduction of the ferroelectric thin film during the back end of the line process including FSG, tungsten CVD (W-CVD), and plasma CVD SiN (p-SiN) passivation. A fabricated 1-Mbit one-transistor one-capacitor SrBi/sub 2/(Ta/sub x/Nb/sub 1-x/)/sub 2/O/sub 9/ (SBTN)-based embedded FeRAM operates at a low voltage of 1.1 V and ensures the endurance cycles up to 10/sup 12/ at 85/spl deg/C and the data retention time up to 1000 h at 125/spl deg/C, which is the most promising for mass production of 0.18-/spl mu/m low-power system LSI-embedded FeRAM and beyond.