Patent · US Expired

Selective area halogen doping to achieve dual gate oxide thickness on a wafer

US6093659A · kind A · utility

16Cited by
10References
17Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 25, 1998
Grant dateJul 25, 2000
Priority date
Expiry dateMar 25, 2018

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH10D84/038
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A method for forming an integrated circuit having multiple gate oxide thicknesses is disclosed herein. The circuit (10) is processed up to gate oxide formation. A pattern (36) is then formed exposing areas of the circuit where a thinner gate oxide (20) is desired. These areas are then implanted with a halogen species such as fluorine or chlorine, to retard oxidation. The pattern (36) is then removed and an oxidation step is performed. Oxidation is selectively retarded in areas (14) previously doped with the halogen species but not in the remaining areas (12). Thus, a single oxidation step may be used to form gate oxides (20,22) of different thicknesses.

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