Stabilization of flatband voltages and threshold voltages in hafnium oxide based silicon transistors for CMOS
US7446380B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 29, 2005 |
| Grant date | Nov 4, 2008 |
| Priority date | — |
| Expiry date | Feb 9, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D64/691
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
The present invention provides a metal stack structure that stabilizes the flatband voltage and threshold voltages of material stacks that include a Si-containing conductor and a Hf-based dielectric. This present invention stabilizes the flatband voltages and the threshold voltages by introducing a rare earth metal-containing layer into the material stack that introduces, via electronegativity differences, a shift in the threshold voltage to the desired voltage. Specifically, the present invention provides a metal stack comprising a hafnium-based dielectric; a rare earth metal-containing layer located atop of, or within, said hafnium-based dielectric; an electrically conductive capping layer located above said hafnium-based dielectric; and a Si-containing conductor.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.