Heterolayered ferroelectric thin films and methods of forming same
US7229662B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Dec 16, 2003 |
| Grant date | Jun 12, 2007 |
| Priority date | — |
| Expiry date | Nov 5, 2024 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10T428/325
- WIPO fieldSurface technology, coating
- WIPO sectorChemistry
Abstract
Heterolayered thin films having ferroelectric/piezoelectric layers of alternating crystal structures and methods of their preparation are provided. In the ferroelectric/piezoelectric thin film, a first layer has a rhombohedral crystal structure and a second layer adjacent the first layer has a tetragonal crystal structure. The layers have a (100) preferred orientation with α-axis normal to the surface of the film. The first layer can be a Zr-rich lead ziroconate titanate layer (e.g., PbZr0.8Ti0.2O3) and the second layer can be a Ti-rich PZT layer (e.g., PbZr0.2Ti0.8O3). Heterolayered ferroelectric/piezoelectric thin film comprising a plurality of such first and second layers in alternating sequence exhibits particularly improved electrical properties.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.