Method of fabricating a highly reliable gate oxide
US6514828B2 · kind B2 · utility
Assignee
Inventors
Key dates
| Filing date | Apr 20, 2001 |
| Grant date | Feb 4, 2003 |
| Priority date | — |
| Expiry date | Apr 20, 2021 |
Classification
- Technology area (CPC H)Electricity
- CPC primaryH01L21/02181
- WIPO fieldSemiconductors
- WIPO sectorElectrical engineering
Abstract
An ultra-thin gate oxide layer of hafnium oxide (HfO2) and a method of formation are disclosed. The ultra-thin gate oxide layer of hafnium oxide (HfO2) is formed by a two-step process. A thin hafnium (Hf) film is first formed by thermal evaporation at a low substrate temperature, after which the thin hafnium film is radically oxidized using a krypton/oxygen (Kr/O2) high-density plasma to form the ultra-thin gate oxide layer of hafnium oxide (HfO2). The ultra-thin gate oxide layer of hafnium oxide (HfO2) formed by the method of the present invention is thermally stable in contact with silicon and is resistive to impurity diffusion at the HfO2/silicon interface. The formation of the ultra-thin gate oxide layer of hafnium oxide (HfO2) eliminates the need for a diffusion barrier layer, allows thickness uniformity of the field oxide on the isolation regions and, more importantly, preserves the atomically smooth surface of the silicon substrate.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.