Selective implementation of barrier layers to achieve threshold voltage control in CMOS device fabrication with high k dielectrics
US7452767B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Aug 7, 2006 |
| Grant date | Nov 18, 2008 |
| Priority date | — |
| Expiry date | Aug 31, 2026 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D84/038
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A method of forming a CMOS structure, and the device produced therefrom, having improved threshold voltage and flatband voltage stability. The inventive method includes the steps of providing a semiconductor substrate having an nFET region and a pFET region; forming a dielectric stack atop the semiconductor substrate comprising an insulating interlayer atop a high k dielectric; removing the insulating interlayer from the nFET region without removing the insulating interlayer from the pFET region; and providing at least one gate stack in the pFET region and at least one gate stack in the nFET region. The insulating interlayer can be AlN or AlOxNy. The high k dielectric can be HfO2, hafnium silicate or hafnium silicon oxynitride. The insulating interlayer can be removed from the nFET region by a wet etch including a HCl/H2O2 peroxide solution.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.