2002 Fiscal Year Final Research Report Summary
Preparation of Ag-alloy top-electrode for ferrolectric films.
Grant-in-Aid for Scientific Research (B)
|Allocation Type||Single-year Grants |
Inorganic materials/Physical properties
|Research Institution||TOHOKU UNIVERSITY |
MASUMOTO Hiroshi Institute for Materials Research, Associate Professor -> 東北大学, 金属材料研究所, 助教授 (50209459)
KIMURA Teiichi Institute for Materials Research, Research Associate, 金属材料研究所, 助手 (10333882)
AKASHI Takaya Institute for Materials Research, Research Associate, 金属材料研究所, 助手 (20312647)
GOTO Takashi Institute for Materials Research, Professor, 金属材料研究所, 教授 (60125549)
JINUSHI Keiichiro Furuya Metals Co. Ltd., Senior Engineer, DMLプロジェクト, 研究員
|Project Period (FY)
2000 – 2002
|Keywords||ferroelectric thin film / nonvolatile memory / lead zirconate titanate / hydrogen atmosphere / Pt electrode / fatigue / Ag-alloy electrode / ferroelectricity|
An Ag-alloy (97Ag-1Pd-2Cu in mol%) was proposed as a new top-electrode for lead zirconate titanate (PZT) films.
1. The composition of the Ag-alloy was examined. The insulation resistance of the electrode has improved to the electrode of the composition which adds Pd of 0.1% or more to the pure silver. A heat-resistant, the insulation resistance, and adhesion characteristic have improved to the electrode of the composition which does Cu from 0.1 to 5% to the virgin silver.
2. PZT ferroelectric thin film was prepared on the Pt/Ti/SiO_2/Si substrate by chemical solution deposition method (CSD method). Pt and the Ag-alloy top-electrode of 0.5mm in the diameter were made on this PZT thin film by the sputtering method. The obtained film was heat-treated by the oxygen and hydrogen atmosphere (N_2-4%H_2), and the following knowledge was obtained.
(1) Oxygen atmosphere
It has been understood for both Pt and the Ag-alloy electrode to be able to maintain excellent ferroelectricity up to 500℃.
(2) Hydrogen atmosphere
In the case of Pt top-electrode, the ferroelectricity of PZT films disappeared after annealing over 3CO℃. Exfoliations of Pt bottom-electrode from substrate were observed after annealing over 300℃.
In the case of the Ag-alloy top-electrode, no chemical reaction between the Ag-alloy electrode and PZT film was observed after annealing at 400℃. The ferroelectricity of PZT film was maintain ed even after annealing at 350℃ using the Ag-alloy electrode.
It is guessed that the Ag alloy electrode developed by this research can be used as new electrode for ferroelectric materials.
Research Products (18 results)