Patent · US Expired

Method for forming high dielectric constant metal oxides

US6020024A · kind A · utility

270Cited by
5References
26Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 4, 1997
Grant dateFeb 1, 2000
Priority date
Expiry dateAug 4, 2017

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D64/693
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method for forming a metal gate (20) structure begins by providing a semiconductor substrate (12). The semiconductor substrate (12) is cleaned to reduce trap sites. A nitrided layer (14) having a thickness of less than approximately 20 Angstroms is formed over the substrate (12). This nitrided layer prevents the formation of an oxide at the substrate interface and has a dielectric constant greater than 3.9. After the formation of the nitrided layer(14), a metal oxide layer (16) having a permittivity value of greater than roughly 8.0 is formed over the nitrided layer (14). A metal gate (20) is formed over the nitrided layer whereby the remaining composite gate dielectric (14 and 16) has a larger physical thickness but a high-performance equivalent oxide thickness (EOT).

Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.