Patent · US Expired

Method for forming a dual gate oxide device using a metal oxide and resulting device

US6787421B2 · kind B2 · utility

42Cited by
10References
19Claims
0Family size

Assignee

Inventors

Key dates

Filing dateAug 15, 2002
Grant dateSep 7, 2004
Priority date
Expiry dateAug 15, 2022

Classification

  • Technology area (CPC Y)Emerging Cross-Sectional Technologies
  • CPC primaryY10S438/981
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A semiconductor device (10) having two different gate dielectric thicknesses is formed using a single high-k dielectric layer, preferably a metal oxide. A thicker first gate dielectric (16) is formed in a region of the device for higher voltage requirements, e.g. an I/O region (24). A thinner second gate dielectric (20) is formed in a region of the device for lower voltage requirements, e.g. a core device region (22). First and second dielectrics are preferably silicon dioxide or oxynitride. A metal oxide (26) is deposited over both dielectrics, followed by deposition of a gate electrode material (28). By using a single metal oxide layer in forming the gate dielectric stack for each transistor, together with high quality silicon dioxide or oxynitride dielectric layers, problems associated with selective etching of the metal oxide may be avoided, as may problems associated with various interfaces between the metal oxide and damaged or treated surfaces.

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