Semiconductor device and method for manufacturing same
US6936901B2 · kind B2 · utility
Assignee
Inventor
Key dates
| Filing date | Dec 29, 2003 |
| Grant date | Aug 30, 2005 |
| Priority date | — |
| Expiry date | Dec 29, 2023 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH10D1/684
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
A semiconductor device is provided which is capable of improving its reliability by using a material having a high relative dielectric constant as a material for its gate insulating film, by suppressing degradation of an EOT (Equivalent oxide Thickness) and by preventing crystallization of the material having a high relative dielectric constant. The semiconductor device (Field Effect Transistor) has a silicon substrate, a seed layer made up of silicon oxide, a gate insulating film made of amorphous hafnium aliminate and a gate electrode made up of polycrystalline silicon formed the gate insulating film. The gate insulating film is so formed that a hafnium concentration decreases monotonously or step by step, whereas an aluminum concentration increases monotonously or step by step along a direction of a thickness of the gate insulating film from the silicon substrate side toward the gate electrode. In a boundary region between a lower layer side region and an upper layer side region in the gate insulating film, the hafnium and aluminum concentrations change continuously.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.