Patent · US Expired

Method for reducing argon diffusion from high density plasma films

US7297640B2 · kind B2 · utility

45Cited by
8References
20Claims
0Family size

Assignee

Inventors

Key dates

Filing dateJan 13, 2005
Grant dateNov 20, 2007
Priority date
Expiry dateAug 19, 2025

Classification

  • Technology area (CPC H)Electricity
  • CPC primaryH01L21/02274
  • WIPO fieldSemiconductors
  • WIPO sectorElectrical engineering

Abstract

A two-step high density plasma-CVD process is described wherein the argon content in the film is controlled by using two different argon concentrations in the argon/silane/oxygen gas mixture used for generating the high density plasma. The first step deposition uses high argon concentration and low sputter etch-to-deposition (E/D) ratio. High E/D ratio maintains the gap openings without necking. In the second step, a lower argon concentration and lower E/D ratio are used. Since observed metal defects are caused by argon diffusion in the top 200-300 nm of the HDP-CVD film, by controlling argon concentration in the top part of the film (i.e. second step deposition) to a low value, a reduced number of metal defects are achieved.

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