Ferroelectric capacitor and method of manufacturing the same
US7473949B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Mar 17, 2005 |
| Grant date | Jan 6, 2009 |
| Priority date | — |
| Expiry date | Sep 12, 2025 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D1/696
- WIPO fieldComputer technology
- WIPO sectorElectrical engineering
Abstract
After a step of fabricating a MOS transistor (14) on a semiconductor substrate (11) and further steps up to bury a W plug (24), an Ir film (25a), an IrOy film (25b), a PZT film (26), and an IrOx film (27) are formed sequentially over the entire surface. The composition of the PZT film (26) is such that the content of Pb exceeds that of Zr and that of Ti. After processing the Ir film (25a), the IrOy film (25b), the PZT film (26) and the IrOx film (27), annealing is effected to remedy the damage to the PZT film (26) that is caused when the IrOx film (27) is formed and to diffuse Ir in the IrOx film (27) into the PZT film (26). As a result, the Ir diffused into the PZT film (26) concentrates at an interface between the IrOx film (27) and the PZT film (26) and at grain boundaries in the PZT film (26), and the Ir concentrations at the interface and boundaries are higher than those in the grains.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.