Multi-step deposition of ferroelectric dielectric material
US8962350B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Jan 30, 2014 |
| Grant date | Feb 24, 2015 |
| Priority date | — |
| Expiry date | Jan 30, 2034 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D1/684
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
Multi-step deposition of lead-zirconium-titanate (PZT) ferroelectric material. An initial portion of the PZT material is deposited by metalorganic chemical vapor deposition (MOCVD) at a low deposition rate, for example at a temperature below about 640 deg C. from vaporized liquid precursors of lead, zirconium, and titanium, and a solvent at a collective flow rate below about 1.1 ml/min, in combination with an oxidizing gas. Following deposition of the PZT material at the low flow rate, the remainder of the PZT film is deposited at a high deposition rate, attained by changing one or more of precursor and solvent flow rate, oxygen concentration in the oxidizing gas, A/B ratio of the precursors, temperature, and the like.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.