Patent · US Expired

Transitional dielectric layer to improve reliability and performance of high dielectric constant transistors

US7235502B2 · kind B2 · utility

6Cited by
0References
12Claims
0Family size

Assignee

Inventors

Key dates

Filing dateMar 31, 2005
Grant dateJun 26, 2007
Priority date
Expiry dateMay 25, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/0228
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A gate dielectric structure (201) fabrication process includes forming a transitional dielectric film (205) overlying a silicon oxide film (204). A high dielectric constant film (206) is then formed overlying an upper surface of the transitional dielectric film (205). The composition of the transitional dielectric film (205) at the silicon oxide film (204) interface primarily comprises silicon and oxygen. The high K dielectric (206) and the composition of the transitional dielectric film (205) near the upper surface primarily comprise a metal element and oxygen. Forming the transitional dielectric film (205) may include forming a plurality of transitional dielectric layers (207) where the composition of each successive transitional dielectric layer (207) has a higher concentration of the metal element and a lower concentration of silicon. Forming the transitional dielectric layer (205) may include performing multiple cycles of an atomic layer deposition process (500) where a precursor concentration for each cycle differs from the precursor concentration of the preceding cycle.

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